Facts & Figuresℹ️ Antenna spire: 300.1 m (985 ft) Type of building: Commercial offices Floor count: 56 Floor area: 109,200 m2 (1,175,000 sq ft) Architect: Norman Foster. Developer: Commerzbank. Structural engineer: Arup, Krebs und Kiefer. Main contractor: Hochtief AG. Owner: Samsung, Korea Cost: DM 600 million. Construction dates: 1994-1997 👉 Visit Structures Insider's homepage for more stories.👈 Declare: The building product nutrition label Architecture🏢 At fifty-three storeys, the Commerzbank is the world’s first ecological office tower and on completion, it was the tallest building in Europe. The project explores the nature of the office environment, developing new ideas for its ecology and working patterns. Central to this concept is a reliance on natural systems of lighting and ventilation. Every office is daylit and has openable windows, allowing the occupants to control their own environment. The result is energy consumption levels equivalent to half those of conventional office towers – the offices are now naturally ventilated for 85% of the year. The plan of the building is triangular, comprising three ‘petals’ − the office floors − and a ‘stem’ formed by a full-height central atrium. Winter gardens spiral up around the atrium to become the visual and social focus for four-storey office clusters. From the outside, these gardens in the sky give the building a sense of transparency and lightness. Environmentally, they bring light and fresh air into the central atrium, which acts as a natural ventilation chimney for the inward-facing offices. Depending on each garden’s orientation, planting is from one of three regions: North America, Asia or the Mediterranean. Source: Foster + Partners For more information regarding the Sustainability aspect of the design read Norman Foster report: "Commerzbank: A Sustainable Skyscraper" Read more: 5 Structures you can't miss when visiting Madrid, Spain Planning a trip to Cologne? This is everything you need to know about Cologne Cathedral What's the most impressive ancient structure in the world? Engineering 🏗 To minimise settlements of the tower it is founded on a 50m piled foundation. The steel structure – up until then unique in Germany – consists of a perimeter tube made of Vierendeel-trusses. The 400m2 office floor petals are supported on 13cm thick steel-composite slabs. The service cores are integrated into building edges formed by the structural steel-composite mega-columns. Eight floors deep, Verendeel trusses provide the structure to span the gardens between the core vertical load members. All of these structural elements wrapped around a central void allow the building’s structure to carry loads like a tube, a very efficient method for forming a structure. Source: Arup.com

What is BIM? Building Information Modeling (BIM) helps create and manage information models in a custom data environment that contains both graphical and non-graphical information (Ingibjörg Birna Kjartansdóttir). The information associated with the 3D Model increases as the project progress increases. Building Information Modeling (BIM) refers to the consistent and continuous use of digital information throughout the entire lifecycle of a built facility, including its design, construction, and operation. BIM is beginning to change the way buildings look, the way they function, and the ways in which they are designed and built. The simplest way to explain BIM dimensions is that they are further details or pieces of information added to a model to help the project team better understand the model. They are the specific ways in which different data types are integrated into an information model. You get a better picture of the project by adding more dimensions of details, such as how it will be organized, its cost, and how it should be maintained. Read more about BIM... 5. Building information modeling: a strategic implementation guide for architects, engineers, constructors, and real estate asset managers by Dana K. Smith The optimal approach to design, build, operate, and maintain buildings With this book you’ll learn: how to implement this new technology as part of a comprehensive systems approach to the design, construction, management, operation, maintenance, and use of buildings. Understand how BIM supports more streamlined, integrated, and efficient business processes throughout the life cycle of buildings, from their initial conception through their eventual retirement or reuse. The benefits of BIM: better quality buildings, lower construction, and operating costs, shorter project turnaround times, and a higher quality of building information to support better business decisions. A plan for incorporating BIM into every organization’s existing workflows enables you to take full advantage of all the benefits that BIM offers. Throughout the book, sample documents and figures help you better understand the principles of BIM and how it works in practice. In addition, first-hand accounts show you exactly how adopters of BIM have gained a competitive edge. Buy at Amazon 4. Delivering Value with BIM: A whole-of-life approach by Adriana Sanchez This book provides a practical and strategic framework to realize value from implementing BIM by adapting Benefit Realisation Management theory. It presents an approach for practitioners aiming to implement BIM across the life-cycle of built environment assets, including both buildings and infrastructure. Also, the book features: wide-ranging information about BIM the challenges of monitoring progress towards benefit goals and the greater context of implementation; a set of dictionaries that illustrate: - how benefits can be achieved - what the benefit flows are and - the enabling tools and processes that contribute to achieving and maximizing them a suite of measures that can serve to monitor progress with examples of how they have been used to measure benefits from BIM real-world examples from across the world and life-cycle phases that show how these benefits can be achieved information on international maturity and competency measures to complement the value realization framework This book has been developed in close collaborative consultation with industry, government, and international research organizations and could be used for industry courses on BIM benefits and implementation for asset management or by universities that teach BIM-related courses. Buy at Amazon 3. Building Information Modeling: Technology Foundations and Industry Practice by André Borrmann This book combines discussions of theoretical foundations with reports from the industry on currently applied best practices. Part I discusses the technological basics of BIM and addresses computational methods for the geometric and semantic modeling of buildings. Part II covers the important aspect of the interoperability of BIM software products and describes in detail the standardized data format Industry Foundation Classes. It presents the different classification systems, discusses the data format CityGML for describing 3D city models and COBie for handing over data to clients, and also provides an overview of BIM programming tools and interfaces. Part III is dedicated to the philosophy, organization, and technical implementation of BIM-based collaboration, and discusses the impact on legal issues including construction contracts. In turn, Part IV covers a wide range of BIM use cases in the different lifecycle phases of a built facility, including the use of BIM for design coordination, structural analysis, energy analysis, code compliance checking, quantity take-off, prefabrication, progress monitoring, and operation. Part V, a number of design and construction companies report on the current state of BIM adoption in connection with actual BIM projects and discuss the approach pursued the shift toward BIM. Part VI summarizes the book’s content and provides an outlook on future developments. The book was written both for professionals using or programming such tools and for students in Architecture and Construction Engineering programs. Buy at Amazon Recommended Dimensions of BIM explained (4D, 5D, 6D,7D) 2. Building Information Management. A Standard Framework and Guide to BS 1192 This book is a guide to BS 1192:2007 Collaborative production of architectural, engineering, and construction information, the standard that provides a best practice method for the development, organization, and management of production information for the construction industry. This book explains in detail: the processes and procedures needed to improve the quality of production information. It will help designers prepare the information before passing it to a construction team to enable a project to be constructed. The adoption of the management processes required to manage information throughout a project lifecycle will also allow the move from a document-centric environment to an information-centric environment unlocking the power of information technology. Buy at Amazon 1. BIM Handbook: A Guide to Building Information Modeling for Owners, Designers, Engineers, Contractors, and Facility Managers The BIM Handbook provides: an in-depth understanding of BIM technologies the business and organizational issues associated with its implementation the profound advantages that effective use of BIM can provide to all members of a project team. This book also includes: Information on the ways in which professionals should use BIM to gain maximum value Topics such as collaborative working, national and major construction clients, BIM standards, and guides A discussion on how various professional roles have expanded through the widespread use and the new avenues of BIM practices and services A wealth of new case studies that clearly illustrate exactly how BIM is applied in a wide variety of conditions Buy at Amazon

by Abdullah Ali Abbasi Civil engineering is all about the construction and rehabilitation of structures. It is one of the oldest known branches of engineering. There are several types of construction. It defines the types of construction based on their nature, environment, and methodology. Large scale structures may include dams, airports, highways, canals, rivers, railways, bridges, abutments, apartments, high-rise buildings, banks, bridges, and military safe-haven, etc. Let’s talk in detail What Does a Civil Engineer Do? Construction of Dams and rivers that store rain and natural stream water are Civil Engineers’ work. Flyovers, Round-About, Freeways, Highways, and other road and infrastructure works are also works that civil engineers do. Irrigation systems for prosperous agricultural growth are also works that Civil Engineers do. Designing and constructing of High rise buildings, public buildings, and housing facilities are other works that civil engineers perform. Have you ever took a flight to move from one city to another or one country to another? You must have used a runway for take-off, a facility to board in, and recreation areas for waiting and leisure. Civil Engineers build these massive structures. I am a Civil Engineer, and I love travelling by railway. I was recently checking videos of Amtrak, and they were fascinating. Do you know who designed and laid the railway lines and all the small and gigantic railway stations? Yes, you guessed it right, Civil Engineers are behind these massive structures. Please read here the Top 5 malls in Islamabad and concerns on the Eighteen Islamabad Project. Cleaner Energy is what we need to save our future generations from the destruction of climatic changes. Clean electricity production on dam turbines is the works of civil engineering professionals. The energy created using water-powered turbines is cleaner in production and also lays off the burden of oil usage. The construction of gardens and other recreational areas is possible due to what civil engineers do. The duties of a Civil Engineer vary as per the major they select in their final year of bachelor’s studies. Masters in Civil Engineering also defines the field an Engineer is ready to practice at a higher level of autonomy and understanding. How hard is Civil Engineering? Civil Engineering is a mildly difficult subject. It requires a lot of numerical works, mathematics, logical interpretations. Students are expected to develop analytical skills to analyze and derive results from various challenges. Students are expected to spend months if not years practising these subjects. Students are expected to learn material properties and the impact of weather on civil works. The numerical solutions that may involve torque, bending forces, shear forces, air pressures, soil profiles, physical phenomenon, geological factors and other areas of science are an important part of learning. Leadership and Problem Solving: Every Engineer is a leader. You are expected to lead several people, and this needs you to hold a cleverer personality. The profession of Civil Engineering expects you to find problems and solve them at a higher rate with great precision. Therefore, you need to develop meditation, patience, fortitude and strategy. Mathematics and Calculations: Mathematics is a branch distant from science. It has more or less a relationship with physics, logic, and abstract ideas. Mathematics is the mother of the Engineering profession, and all the majors of civil engineering contain the influence of mathematics in one way or another. Anyone looking to pursue a career in Civil Engineering is expected to keep a strong knowledge of Trigonometry, Differential Equations, Algebra, Calculus, and Probability. Efficient Learner: A student admitted in Civil Engineering technology is expected to learn a variety of ideas efficiently. There are more than six subjects per semester, each having a minimum of four assignments and four quizzes. Then there comes extracurricular activities and routine life engagements. Every student is expected to grasp the ideas delivered or tutored during a lengthy 1-hour lecture, much time to lose attention and patience. There is no way to escape boredom. Benefits of Effective Communication: I am a Civil Engineer with hands-on real-time field experience. I can’t express the importance of effective communication “where necessary” in Civil Engineering. You need to hide and reveal ideas as per their strategic importance. However, when the time comes, you are required to express with full zeal and zest. We have written a detailed article on the benefits of communication that all help develop a charismatic personality. Students get their hands on a variety of life-changing subjects. Communication Skills, and Logical Reasoning. Analysis and Cognitive Abilities. Usage of ICT in a variety of problems and conveying ideas using good writing abilities. Structural Analysis and Integrity Measurement. Irrigation Engineering, and Fluid Mechanics for sustainable environment and improved fluids physics in action. The integrity of Soil and pre-foundation studies for public safety and structural integrity. Usage of Computer Aided Drawing and Designing is an essential outlook of the importance of technology in Civil Engineering works. Civil Engineers also learn subjects like computer programming, and differential equations for their usage in the military, economy, and strategy. Technology Fusion with Ancient frontiers building and construction for a prosperous and excelling lifestyle. Construction work was first named civil works in 18 century. Before the 18th century, there was no title of a civil engineer. There was also no syllabus and teaching school for the subject. Civil Engineering is a field of challenges and stress. Civil works are required to perform in changing and challenging circumstances. It also requires a lot of patience. Site conditions are usually not favourable for civil engineers. However, termination of construction because of the changing environment and climate conditions is possible. But these cases are rare, and work has to be carried in all weather conditions. History of civil works. Branches Of Civil Engineering There are various branches of civil engineering, all dealing with different sectors. The branches of civil engineering are differentiated based on the nature of the work. However, these branches are related to research programs after a bachelors degree in civil engineering. Water Engineering is one of the desired fields. Water is life. Everyone needs water to live on. So, it is the most important branch of civil works. Structural engineers design and analyze. It deals with public safety. Transportation is the main sector of civil engineering works. Million of people daily use different modes of transport. Proper handling can save a lot of time. It can also help in reducing depression. Management has to manage the projects. This involves techniques to handle different phases of a project. An amazing nature shows off. Civil engineers usually work on sites. But they have office work too, to handle. Their duties may include preparation of working schedules, assignment of duties, crew management, material procurement, human resources, conflicts management, project management, and project exploration. To ensure the safety of structures, a civil engineer is solely responsible. However, a team of civil engineers performs different duties at a particular time for the completion of a project. A civil engineer keeps the right of terminating a project if it isn’t safety compliant. How to Become a Civil Engineer? The person who wants to peruse their career in the field is called a civil engineer. Due to the complex nature of civil works, it requires proper qualification. Mostly after the completion of a bachelors degree, a person can be called a Civil Engineer. Safety is the highest priority of a civil engineer. A civil engineer also keeps the right of terminating a project if it isn’t safety compliant. You can find the work of civil engineers all around you. When you have to visit the washroom to clean yourself, civil engineering works offer a variety of services to you. Whenever you clean your utensils with clean water, remember a civil engineer at work. If you feel safe inside your home, say thanks to the civil engineers. The roads you use to commute daily are an outcome of civil engineering works. Civil Engineers are finely crafted by the bridges that connect you and the recreational areas that help you rejoice in your feelings of happiness. Civil engineers construct the front line of defence of nations. A civil engineer can help you win a war, as he masters in terrain selection. We love sand. We live in the desert. Our Life is under the sun. Civil engineering is the job of a gentleman. We expect an increase in demand for civil engineers at a pace of 6% in the future. Structures expire and we have to rebuild them otherwise we have to repair them. On the other hand, the world is building at a higher pace. Developing countries are spending billions on the construction of their infrastructure. Whereas, war-torn countries are losing their already built structures. The population of this world is increasing. It requires an increase in all services. These facilities include Housing schemes. New hospitals. New schools. Business centres. Parking areas. Community centres. Civil Works – Engineering Practices A typical hierarchy of civil engineering works includes a preliminary examination, designing, building, supervision, operation, construction, and maintenance of a structure. A survey before working. Site instigation helps you know the site in detail. Design inquiry can help a lot. Supervision means the construction under the instructions of a civil engineer and in compliance with professional practices. Civil Engineers should maintain the operation of works under optimal conditions. Both in terms of nature and environmental conditions. A Civil Engineer should maintain a log of material acquired. Daily progress reports are also mandatory to produce. And can help in conflicts resolution. Project management includes an indication of discrepancies in drawings and methodology adoption. Civil Engineering Law (FIDIC) In every sector of life, the law has its importance. Whenever we deal, there is a chance of struggle. The resolution of the dispute is possible by enforcing the law. There are technical difficulties in the usage of general law. However, civil engineers have made their law. There is a complete system. This system is powerful enough to resolve issues. Law is life. It creates ease. It helps! History of Civil Engineering Engineering profession dates to 5000 Bc. Civil works masterpieces are visible all around the planet. During the exploration of archaeological sites, a complete system of life indicates the mastery of ancient professionals. These discoveries show the usefulness of Civil Engineering. An amazing civil engineering structure from ancient times is in the Middle East, the Egyptian-Pyramids. The weight of the stone weighs several tons. Top 10 Impressive Civil Engineering Structures Egyptian Pyramids is located in Egypt. Great Wall Of China is in China. Aqueduct Of Segovia is in Spain. Brooklyn Bridge is in New York City. Panama Canal is in Panama. Hoover Dam is in the United States. Golden Gate Bridge is in San Francisco. English Channel Tunnel is in France. Burj Khalifa is in Dubai. Qingdao Bridge is in China. These projects require a lot of time and effort. In civil works, we often meet accidents. Many people have to face a life-lasting illness. For construction works, safety should be the highest priority. Old is Gold. Gold is Real. Real is Worthy. Civil Engineering represents Nature, Civil Engineers Improving Lives Public works departments are responsible for providing facilities. Governments allocate funds for them. They receive their pays from the government. Civil Engineers improve living standards. The sustainability of a structure ensures the safety of any nation. Whereas, public health is also a direct beneficiary of civil works. Pure water reaches people after covering a long distance. Researchers say that pure water can be the next global issue. Climate change is emptying the global water reserves steadily. However, water researchers are working to save water. Better housing facilities are improving global living standards. Sustainable structures are saving millions of lives. Earthquake resistance, improved safety against rain and floods, are making us live safer. Improved Defense of security facilities is made possible. The arguably strong structures are a blessing in today’s chaotic world. Engineering works improve living standards. Dam construction Importance Of Technology In Civil Engineering Civil Engineering relies on the usage of technology. From the production of raw material to its usage, all processes are performed using technology. Various technologies include heavy machinery, surveying tools or instruments, laboratory equipment, and other safety gadgets. Heavy machinery includes dumper, shovel, tractors, generators, concrete pumps, blowers, water pumps, cranes, vibrators, etc. Surveying tools include theodolite, total station, measuring tapes, recorders, GPS systems, and other modern devices. Laboratory equipment includes oven, heaters, sieves, mixers, material testing equipment, UTM’s, etc. However, cutting edge technology can play a vital role. A widely discussed such technology is self-healing concrete. This concrete is to overcome the cracking problem. Soon after casting the concrete generate cracks. This concrete can recover from those cracks on its own. The bacteria start multiplying its growth. Hence, overcomes the cracking problem. The usage of Virtual reality is next on this list. This technology is used to see the architectural view of the building on site. This helps in removing the bad appearance of the building before construction. Technology also takes the help of augmented reality. Let’s now talk about 3d printing. With the usage of this technology, we generate 3d models. These models can be taken against virtual reality. To ensure public safety civil engineers make use of tech. Computer software is a must to achieve the required results. On a massive scale, their importance increases. Commonly used software are as below SAP 2000 is often used. Sketchup helps in 3D modelling. E-Tabs is also used. Civil Engineering We make use of technology for excavation. The architectural stone is used to increase the beauty of the civil works. It requires great care and a high finish. These processes include the usage of technology. A Revenue Generating Field The Civil Engineering field generates a lot of money. We have discussed several business opportunities. Millions of people are working in this field. Still, millions are trying to expand their circle of influence. All these working generate a lot of money. Only the Cement industry makes billions every year. Let alone the labour industry, professional services, and other production facilities. There are many ongoing construction projects like Eighteen Islamabad, Palm Jumeirah, and Fehmarn Belt Fixed Link (Denmark). Millions are spent every year on painting civil structures around the globe. It requires several labour contractors to perform activities and get the jobs done. Several engineers supervise the civil works and ensure public safety and structural integrity. As small mistakes can ruin a project and incur everlasting damages in cases of money and life loss. Therefore, proper planning, execution and monitoring of civil works are necessary for a successful engineering project. Careful Practices To Increase Revenue Adoption of Technology Solutions. Better planning can help you a lot. Skilled workers are a blessing. Improved safety will increase the work pace. Better communication matters. Rules implementation is necessary to succeed. Market Analysis can save you in difficult times. A Civil Engineer is required to maintain a record of all civil works. Keep close ties with the working crew. Respecting and solving problems and issues of workers for smoother works execution. Awarding workers bonuses for their hard work can expedite the pace of Civil Engineering works. Necessary inter-stakeholders meetings can help bolster confidence and better understanding. Famous Types of Civil Engineering Structures: Civil Engineers use wood as a material for Civil Engineering Works. Wood structures are still seen as a symbol of luxury and used in the majority of the united states. We often use wood as an architectural element and is affordable. Good quality wood is expensive, and we rarely use it. However, its beauty and long life make it second to none. Stones are also used as a building material in Civil Engineering Structures. They are not very good independent structures in case of earthquakes and landslides but still are widely used to build heavy structures where cracks are breakages are tolerable, as in the case of boundary walls. Stone structures are hefty and difficult to work. Frame Structures are the most popular Civil Engineering structures. These structures are comprised of concrete and steel. These are by far the most efficient and safe engineering structures. We lay foundations then work on columns, beams, and slabs. These structures are smart and we can use bricks, blocks, or wood partition walls for separating rooms and other areas of a building. Scope Of Civil Engineering The options available for working in civil engineering are vast. Several fields are linking to civil engineering. All these various fields increase the importance of the field. Whereas, these signs increase the trust of the public. This increase in trust helps in creating new jobs. So, it shows an increase in reputation. Hence, an increase in trust increases business. Private sector firms are also investing in civil works. Land purchasing is a safe way to invest. People invest in civil projects as it's safe. Due to inflation the worth of land always increases. Peace In the United States, more than 2 million people work in this field. It produces 10 billion tons of concrete in a single year. China is a big consumer of concrete. During 2017 it alone produced more concrete than the entire world. Here it is important to mention that the production of cement emits carbon and other gasses. These gases contribute to climate change. It is necessary to reduce the usage of concrete. Millions of people die every year due to these harmful gases. Many people especially infants have to face genetic disorders. Societies Of Civil Engineers There are various societies of Civil Engineers. Students and professionals interact there with each other. They publish journals to educate readers. These societies work for the welfare of civil engineers. They also provide a platform for discussing ideas. These societies include the American society of civil engineers, ICE, etc. Many schools are teaching Civil Engineering. How can you know about the quality of a civil engineering institution? It is based on the teaching quality and research output. The first Civil Engineering student was from 18 century. Future of Civil Engineering The future of Civil Engineering is safe with pros and cons. There is a chance of an increase in economic activity around the globe in the field of Civil Engineering. And as the population increases, so the facilities have to. Thus the field has the capacity of embracing expansion. One can say the future is bright by relating it to the increase in the population. The more there are people, the more are the opportunities for Civil Engineers and profession. Although the field is rough & tough in terms of working conditions and working wages in under-developed countries, expectations are great for the coming future. civil works We are entering the era of modern building materials, strategies, and techniques. The field of civil engineering is expected to grow in 2021 and beyond. by Abdullah Ali Abbasi

Introduction Concrete is an artificial building material obtained by mixing cement, fine aggregate, coarse aggregate, and water in suitable proportions. Cement act as a binding material and it forms a paste with water. It holds coarse and fine aggregates together to form a solid mass. The concrete mix is used for constructing slabs, roofs, retaining walls, pillars, dams, etc. Concrete is a mixture of cement, aggregate, and water, the properties of constituents affect the properties of concrete. The quantity of cement and water affects the strength of concrete. The size and shape of aggregate affect the strength and workability of concrete. Compaction (the method of removing voids between the aggregate) also influences the properties of concrete. There are two stages for concrete · freshly prepared concrete i.e. in plastic stage · hardened concrete (after attaining its full strength) Components of Concrete The components of concrete are as follows: Ø Cement: Cement is the most important ingredient of concrete. It is used to bind the fine and coarse aggregates together. Most of the concrete is prepared with ordinary Portland cement. Other special varieties of cement-like waterproof cement, rapid hardening cement, and high alumina cement are used under specific circumstances. Ø Fine aggregate: Fine aggregates are inert or chemically inactive material. River sand, crushed stone, crushed gravel, etc. are used as fine aggregate. Fine aggregates are used to make the concrete denser by filling the voids of coarse aggregates. It is used to make the concrete mix economical and it reduces the shrinkage of concrete on hardening. Ø Coarse aggregate: Uncrushed gravel, broken bricks crushed stone, etc. are used as coarse aggregate. They make concrete strong and tough. Ø Water: Water is used for mixing concrete. It should be potable (fit to drink). Water acts chemically with cement to form a paste for binding the aggregates. It also enables the concrete to flow into molds. Water required for hydration of one part of cement is about 0.3 part of water, but for lubricating, the aggregate extra water is required. Hence, the water-cement ratio for the medium and high strength concrete is 0.6 and 0.35 respectively. Insufficient quantity of water makes a concrete mix harsh and unworkable whereas an excess quantity of water causes bleeding and segregation of concrete. The strength of concrete is inversely proportional to the water-cement ratio. That is if we decrease the water-cement ratio we can increase the strength of concrete. But for water-cement ration less than 0.35 it is very difficult to work with than concrete. Water cement ratio depends upon the following factors: · Quality of cement · Quality of aggregate · Internal moisture content · Atmospheric temperature · Size and age of test specimen Sometimes ingredients other than the above are added in concrete for improving or imparting certain properties and these ingredients are known as admixtures. The addition of admixtures improves durability, workability, water-resisting power, the strength of concrete, setting time of concrete, reducing shrinkages, imparting color, reducing bleeding, etc. Commonly used admixtures are lime, alum barium oxide, soap, aluminum sulfate, calcium chloride, mineral, and organic oils, bitumen, etc. Properties of freshly prepared concrete The properties of freshly prepared concrete are as follows: · Workability: Workability is the ease with which concrete can be mixed, transported, and placed in position. · Segregation: Segregation can be defined as the separation of the constituents of a concrete mix during the transportation of prepared concrete. · Bleeding: Bleeding is defined as the separation of water or mortar from the freshly prepared concrete. This is due to the high water content in the mix. This will cause the formation of porous, weak, and non-durable concrete at the top of the placed concrete. Properties of hardened concrete Properties of hardened concrete are as follows: · Strength: Good quality concrete in a hardened state should possess desired crushing strength. The compressive strength of concrete at 28 days after casting is known as the designed strength of concrete. · Durability: It is the ability of concrete to resist weathering agents, chemical action, seawater, fire, and wear. Durability depends upon the quality of aggregate and water-cement ratio. · Shrinkage: Concrete experiences shrinkage during hardening. This depends upon the constituents of concrete, atmospheric temperature, and size of the structure. It can be minimized by using the designed quantity of water-cement ratio and by proper curing. · Creep: Creep may be defined as the time-dependent elongation of concrete structure under the external loads. It depends on the water-cement ratio, nature of aggregate and its grading, the humidity of the air, intensity and duration of load, and age at the time of loading. · Fire resistance: It has good fire resistance properties and acts as a good insulator. · Density: According to BS EN 1922-1-1, the weight density of concrete should be approximately 2500kg/m3. · Bond strength: The strength of the bond between the steel reinforcement and the surrounding concrete is a very important factor for RCC structures. Bond strength is determined by pullout tests i.e. the load required to cause a slip of 0.25mm divided by the area of contact between the steel bar and concrete. · Elasticity of concrete: Concrete behaves elastically only up to 10 to 15% of its ultimate strength. Up to that loading, condition stress is directly proportional to strain. Modulus of elasticity of concrete depends upon the strength, water-cement ratio, moisture content, quality of aggregate, and age of the structure. · Permeability: Concrete consists of so many pores. Permeability of concrete is a function of porosity, size, and continuity of pores. The porosity of cement gel is about 28% but its permeability is 7×10-14 cm/sec. It is due to the fine texture of hardened concrete. Factors that affect the permeability of concrete are water-cement ratio, quality of aggregate, curing, uniformity of concrete, etc. · Thermal properties of concrete: Basic thermal properties of concrete are thermal conductivity and diffusivity, specific heat, and coefficient of thermal expansion. These properties of concrete are required for the study of insulating properties of concrete, sweating of concrete in different climates, temperature conditions in mass concrete. · Resistance to wear and tear: Concrete floors and road and runway pavements are subjected to abrasion and impact, which cause wear of the surface. The wear resistance of concrete can be improved by using a lower water-cement ratio, lowest slump, good quality graded aggregate, etc. Also for you: CMG Headquarters - Steel Fiber Reinforced Concrete Structure Applications of prestressed concrete Testing of concrete Compressive strength test of concrete The compressive strength of concrete depends on the water-cement ratio, grading of aggregate, the proportion of constituents, type of aggregate, mixing efficiency, etc. The strength of the concrete usually increases with the age. Among all other properties of concrete, the compressive strength of concrete is the most important property and this value is used for the design of structures. Hence for the design, we must know the strength of concrete. For compressive strength testing, first, prepare 12 cubes of concrete with 15cm sides. 6 cubes will be cured for 7 days and the rest of them will be cured for 28 days. The cured specimen is loaded in a compression-testing machine at a standard rate of 315 kN/minute. Note down the load at which the specimen ceases to break. Compressive strength can be calculated using the formula given as follows: Similarly, we can also find the compressive strength of concrete for 28 days. REFERENCES 1. P. Bamforth; D. Chisholm; J. Gibbs; T. Harrison, Properties of Concrete for use in Eurocode 2, Cement and concrete industry publication, sefindia.org https://www.sefindia.org/forum/files/properties_of_concrete_for_use_in_eurocode_2_135.pdf 2. Pablo Tamayo; Joao Pacheco; Carlos Thomas; Jorge de Brito and Jokin Rico, Mechanical and Durability Properties of Concrete with Coarse Recycled Aggregate Produced with Electric Arc Furnace Slag Concrete, Applied Sciences, 2020, doi:10.3390/app10010216 3. Md. Shahrior Alam; Syed Ishtiaq Ahmad, Concrete and It’s properties, Presentation · 2020, doi: 10.13140/RG.2.2.18980.50564 4. Tehmina Ayub; Sadaqat Ullah Khan and Fareed Ahmed Memon, Mechanical Characteristics of Hardened Concrete with Different Mineral Admixtures: A Review, The Scientific World Journal, Hindawi Publishing Corporation, 2014 http://dx.doi.org/10.1155/2014/875082

137,500 elephants, each weighing an average 6000kg corresponds to 330,000 of concrete used for the Burj Khalifa 🐘 Also, 55,000 tonnes of steel rebar, as well as aluminium, glass, stainless steel and silicone, was used. 👉 Visit Structures Insider's homepage for more stories.👈 Engineering 🏗 Materials ♺ used for Burj Khalifa’s construction: Concrete:🧱 High strength concrete varying from C50-C80 concrete strength was used. A huge pile supported raft, 3.7m thick utilised 12,500 cubic meters of 50 MPa cubic strength concrete that incorporated 40% fly ash and W/C ratio of 0.34 in its mix. Furthermore, C60 concrete was used for the foundation piles. Due to the highly corrosive groundwaters of the dessert, cathodic coding protection was required for the piles. Each floor consists of 200mm to 300mm two-way reinforced concrete flat plate slabs spanning in modules of 9m. From level 156 and above a steel braced frame structure is placed. Steel:⛓ steel brace frame structure was used for the construction of level 156 and above with a purpose of reducing the structures overall weight. Check us out on Instagram : Structures Insider on Instagram: “Burj Khalifa the worlds tallest structure height at 829.8m ‼️ United Arab Emirates Construction facts: ⛓ Concrete used :…” Read more: 5 Structures you can't miss when visiting Madrid, Spain Planning a trip to Cologne? This is everything you need to know about Cologne Cathedral What's the most impressive ancient structure in the world? You May Also Like:

General Informationℹ️ Location: East Third Ring Road Guanghua Road Beijing, China Construction dates: 1 June 2004 - 16 May 2012 Floor count: 51 Roof: 234 m (768 ft) Floor area: 389,079 m2 (4,188,010 sq ft) Developer: China Media Group Architect: Rem Koolhaas and Ole Scheeren: Office for Metropolitan Architecture East China Architectural Design & Research Institute Structural engineer: Ove Arup & Partners. Main contractor: China State Construction and Engineering Corporation. Visit Structures Insider's homepage for more stories. The new headquarters of China Central Television (CCTV) is a 234m tall building with a highly unusual shape, described as a 'three-dimensional cranked loop'. The building is formed by two leaning towers, bent 90° at the top and bottom to form a continuous tube. The building’s primary support is achieved through the irregular grid on its surface, a visible expression of the forces travelling through the tube structure; the smaller the diagonal pattern, the stronger the load and the greater the support. “The bracing arrangement is reflected in the façade design, providing a visible representation of the complex force distribution throughout the building structure. ” The braced tube structure also gives the building the required robustness to withstand the likely seismic activity in the area and therefore provides an extra level of safety. Source: Arup Engineering System 🏗 Αll the structural support elements in the building are of structural steel, except some external columns are steel-reinforced concrete columns due to the magnitude of loads they are designed to carry. The floors are composite slabs on steel beams. You May Also Like: The Pros&Cons of Steel fibre reinforced concrete (SFRC) explained Fibre-reinforced concrete is a composite material comprised of traditional concrete and steel fibres. Steel fibres increase durability and ductility of the reinforced concrete mix as well as decrease... Read more... Primary Structure From the onset, it was decided to adopt an external skin of leaning columns, horizontal edge beams and triangulated bracing on a two-storey pattern to form an enclosed tube structure to support the building. Furthermore, the braced tube structure affords a multitude of alternative load paths. Such a robustness feature is highly desirable, especially in seismically sensitive Beijing. It also provides safety in the event of an extreme design incident, such as blast removal of a major column in the building. The external diagrid structure is also boldly expressed in the building’s façade. It visually expresses the pattern of forces in the external tube, reinforcing the transparency between structure and architecture, a strong philosophy in the building’s design. The unique diagrid pattern in the external structure was arrived at after extensive iteration and optimization, in close collaboration with the architect. Internal Trusses were used to cope with the floor plans required, Source: China Central Television Headquarters - Structural Design Read more: Concrete variable radius arch dam explained New York City is planning to expand Manhattan into East River to battle climate change Dracula's luxurious residence has 57 rooms and has its own private wooden church Essential Books for Civil Engineers Amazon's Choice

Article by: Gobinda Burman from: Green Environmet BASIC PRINCIPLES OF PRESTRESSING A beam resting on supports at each end trends to bend under its own weight and under applied loading. This causes compression along the top part of the beam and tension along the bottom part. In other words, there is a tendency for the bottom of the beam to stretch. Concrete is strong in compression, but weak in tension, and for this reason, a plain concrete beam has little strength. The tensile weakness of concrete is overcome by casting steel bars into the sections where tension is likely to occur. When a load is applied on beam, cracks still occur in the concrete, but the tension is carried by the steel reinforcement. The principle of prestressing is to compress the beam before it is loaded in such a way that stresses are induced in the section which is opposite in action to those arising under loading. Thus the bottom of the beam is compressed by the prestressing so that tension arising when it is loaded will be entirely neutralized. Furthermore, the compression in the concrete is also of great importance in resisting shear. If one imagines a prestressed beam as a row of blocks pressed together, it is easy to see that if they are pressed together sufficiently tightly they will not fall out when a load is applied. This condition aided by the device of sweeping cables upwards at the end of the beam will usually eliminate the need for steel reinforcement to resist shear stresses. ADVANTAGES OF PRESTRESSED CONCRETE The rapid increase in the use of prestressed concrete is due to the fact that it is technically and economically superior to other methods of construction. Since the size of prestressed members is less than that of the conventional reinforced concrete members, the dead load of the structure is often reduced sufficiently, hence savings of materials in structural members. The use of prestressed concrete as a structural medium for bridge construction has been gaining popularity. With the increase in transportation, the requirement for bridges became acute and the shortage of general building materials gave an impetus to use of prestressed concrete in all civil engineering activities. The development of prestressed concrete technology over the last two decades can be attributed to the research, development, improvement and advancement of materials, technology and construction techniques. The existing materials used in construction were better utilized and their properties enhanced, new materials developed to suit the special needs of prestressed concrete. The development in technology is also seen in the concept of form-work and analytical techniques. Also for you: What are the Advantages of Using Steel Fibre Reinforced Concrete instead of traditional Rebar? APPLICATIONS OF PRESTRESSED CONCRETE 1. FOUNDATION: Prestressed Concrete Piles: Prestressed concrete piles have been used extensively in the construction of buildings and marine structures. Due to its high strength for handling and a high degree of durability in seawater and other adverse environments, the use of prestressed concrete piles became very popular in the construction of marine structures. The prestressed concrete piles have many advantages in comparison with conventional piles - a few of them are: High load-carrying capacity. Crack-free under handling and driving. Ability to take up-lift (tension). Can bear hard-driving and can penetrate hard strata. Durability in an adverse environment. High column strength. In view of the above advantages, the prestressed concrete pile is an ideal choice for deep foundations with heavy loading on weak soil. At present, prestressed concrete piles are being used as sheet piles, fender piles and soldier piles. It also used for carrying vertical loads with different soil strengths and found to be durable in varied environments ranging from sub-arctic to the desert. Rock /soil Anchors: Prestressing techniques are now used for strengthening an existing structure by anchoring it to the rock or soil. In places where rocks are not available immediately below the ground level, rock-anchors are used to anchor the pile to the rocks that are situated at very large depth. The use of prestressed anchors avoids the driving of the pile all the way to the rock which is available at very large depth. The pile is driven only to a certain depth, depending on the soil condition and prestressed cable is sent through the pile to the rock. The cable is then stressed and grouted. 2. BRIDGES: The spectacular contribution of prestressed concrete can be seen in the construction of superstructures of bridges. It has been extensively used in both rail and road bridges. The technique of prestressing lends itself beautifully to the construction of different types of bridges. a. Simply Supported Bridges: They are adopted for medium and short spans. The cross-sections of these beams maybe I, T, two T's or Box shape. The girders can be pre or post-tensioned. These beams may be precast or cast-in-situ and are usually supported by neoprene or other types of bearings at either end. b. Cantilever Bridges: This method is usually adopted for longer span bridges. In this method, there will be cantilevers extending from each of the piers. There will be a suspended span of the shorter length to connect the cantilevers. The cantilevers are usually extended by anchoring precast segments of short length. Each segment is anchored to the balancing extension on the other side of the pier. c. Cable-Stayed Bridges: Extremely long spans constructed by using this method of construction. In this type of construction, the deck or slab is held by a number of prestressed cables anchored to the anchor tower. Using this method spans up to 300 m can be constructed. Other types of bridges like bridges with Bow String Truss, Stressed Ribbon Deck, and Arch Bridges are included. Recommended to you : 3. MARINE STRUCTURES Prestressed concrete has gained acceptance in the field of marine structures due to its durability, strength and economy. Its application to foundations has already been discussed in the earlier section. Prestressed concrete is now being applied increasingly in the super-structures of the marine projects. A few types of marine structures where prestressed concrete has been adopted are: Coastal jetties. Wharves. Bulkheads. Offshore platforms. Navigation structures. Protective fenders. In these structures, the prestressed concrete elements may be in the foundation, such as bearing pile, sheet pile, etc. or in the super-structure, such as the deck, beam slab, etc. It is a well-known fact that marine construction has many problems of its own in its construction procedures. The difficulty at the site especially for the movement of materials and workers, makes quality control a difficult exercise. Further, highly skilled labour is required in such projects. Such labour is either not available or available at a very high cost. All such factors show that precasting is an ideal choice for marine structure. In precasting, the efficiency and economy can be increased by means of prestressing, especially by pre-tensioning. The pre-tensioned materials can then be made to act monolithically by post-tensioning them subsequently. 4. WATER CARRYING STRUCTURE a. Aqueducts: Prestressed concrete is found to be the ideal choice for the construction of aqueducts due to its water tightness and crack-free surface. Prestressed concrete, due to its high strength, enables the construction of long-span aqueducts with high water carrying capacity. b. Water Tanks: Circular water tanks are also constructed by using prestressed concrete. They withstand higher circumferential stress than R.C.C. The wall thickness of the prestressed concrete tanks is much less than that of R.C.C because of its high strength. With these advantages, the use of prestressed concrete for the construction of overhead water tank and reservoirs is gaining popularity. 5. INDUSTRIAL  STRUCTURES Application of prestressed concrete in the field of construction of industrial structures is getting momentum. The tie members of the trusses are usually prestressed. The advantages of using prestressed concrete are: longer spans of trusses can be constructed. The aesthetic look of the structure is enhanced. 6. PRETENSIONED PRODUCTS In the field of pretension, much progress has made to great advantage. The extensive manufacture of prestressed electric transmission poles is just one of the many applications of pretension. The recent and important addition in the list is the railway sleeper. A number of plants manufacturing these sleepers springing up in every corner of the world. Precast pre tensioned members are also used extensively for prefabricated houses. This application has potential and offers excellent scope for development and diversification. 7. NUCLEAR STRUCTURE In this atomic age, the concept of prestressed concrete lives up to its reputation as the technology that can offer solutions even to the most difficult and intricate problems faced by the civil engineering industry. The designers of the reactors have realized the advantages of prestressed concrete and are now designing their pressure-vessels and container-vessels of the reactors, recommending the use of prestressed concrete. This application should prove the versatility and superiority of the concept of prestressed concrete over conventional methods. Article by: Gobinda Burman from: Green Environmet

Introduction In concern with embodied energy in construction, I attempt to find an ecologically friendly material. Through researching various vernacular earth architecture around the world and comparing these through different eras of earth building, I’m trying to discover how it can and is, this ancient practice, used nowadays. How going back to the absolute basics our ancestors used can help the current climate crisis we are facing. Gathering information and proposing a new modern pillar of architecture. Carrara Marble Quarry, Italy Watching the “Anthropocene: The Human Epoch”1 film, I was mesmerized by the Italian Carrara marble quarry. After seeing this beautiful senary it got me thinking, what is the cost on our planet to export one of the most prestigious marbles worldwide and how can we cut down on embodied energy. The most used material, concrete, I found out it contributes about 8% of the world’s carbon dioxide emissions. If the entirety of the cement industry was combined into a country, it would be the third-largest emitter, behind China and the US. The industry contributes more CO2 than aviation fuel and it’s not far from the global agriculture industry (12%). But this is not slowing down, the cement industry quadrupled since the 1990s and is likely to increase even more in the future if we won’t find greener alternatives. 1 Anthropocene: The Hum Also for You: Soil Mechanics: Effects of water on soil | Structures Insider Mudbricks Trying to find a material with low embodied energy, I didn’t have to look far but just below me, Earth! Mudbricks have been used widely across the globe for centuries as the main building material. For some of the greatest ancient civilizations, Mesopotamia, not only used it as a housing material but also for megastructures that are still standing centuries after construction. Such as the Taq Kasra which is the largest single-span vault of unreinforced brickwork, made from mudbricks, in the world till this day. Truly shows the durability of soil. That got me questioning how can this material that withstands the test of time can be adapted to the modern world and practices. Mudbrick is a rectangular mold-made brick from the soil, chopped straw, and water. Vernacular architecture is the “native science of building”1 as mentioned by Oliver P, so why don’t we go back to this. 1 Oliver Paul, Built to meet need: culture issues in vernacular architecture, Architectural Press Started by researching 4 random buildings on the list given to try and figure out what I wanted to focus on. When researching the Yaodong Complex in China, which are underground house complexes I realized I wanted to investigate earth architecture and how it was done in vernacular architecture and how that is implemented nowadays. Through this study am trying to see if the earth is a reliable and efficient material to use for the future construction of structures. Starting off, the Adobe Pueblo in Mexico, are mudbrick houses built in the southeast of the USA and Mexico. Its multistoried rooms, up to 5 stories, usually in a pyramid-like arrangement where the roof, that were made from wooden posts, straw, mud, and plaster, can act as a terrace to the room above. Movement between them was usually accomplished with wooden ladders and each could house multiple families. Following on to Cyprus traditional houses that were made from mudbricks with a plaster finish on each side of the walls, creating great insulation for the subtropical Mediterranean climate. They are usually 1-2 stories houses with an enclosed yard and a secondary structure that can be used as storage or as a barn. Moving on to the incredible Shibam Hadramawt in Yemen, known as the “Manhattan of the desert”. They are the first high-rise apartment buildings, made from mudbricks, dating back to the 9th century, they vary from 5 to 11 stories high. A truly great example of the extent and strengths soil can have when it comes to construction. Stepping into the post-industrial interpretation of earth architecture things start to change and new technologies are emerging, making earth architecture even more efficient and easier. Hassan Fathy, an Egyptian architect, created a movement around the 1940s, having a political motive of the disfavor of both political ideologies, he promoted the third one. An ideology of political, economic, cultural, and technological self-sufficiency. Boycotting cement imports and reviving the adobe ancestral tradition. New Baris, is a very well-thought-through mudbrick complex in Egypt (1967) that ameliorates an extremely harsh environment without mechanical means. Fathy achieved that by adapting medieval practices in Cairo. Adding a second chimney with incline metal louvres, which was extremely experimental in such harsh heat conditions, was extremely successful due to visitors reporting shivering with cold in the lower levels even on the hottest summer days. The community of La Luz in Albuquerque, New Mexico by Antoine Predock is a complex of houses built-in 1967. It is made from adobe walls from on-site materials, its massive adobe walls act as heat reservoirs and form acoustical barriers. Some walls are painted white to bounce light in rooms or patios with the buildings also considering the sun and wind patterns of the area where the west side offers mostly blank walls to lower sun exposure and the patios offer shelter from the winter winds. The Chapel of Reconciliation in Berlin, by architects Retermann and Sassenroth built-in 1990, has a core of rammed earth. The remains of the former chapel, which was destroyed in 1987 because it was in the Berlin death strip, are integrated into the thick rammed earth walls. A reiteration of earth architecture is rammed earth. Rammed earth is created by compacting subsoil material, unbaked earthen construction unlike mudbricks, in temporary formwork. Compacting multiple layers of soil can create a high aesthetic appeal, passive hygroscopic humidity regulation, and more important its extremely low embodied energy. All this can be built on-site with soil found there or from other constructions excavation waste. Some alterations of rammed earth are factory prefabricated walls and stabilized rammed earth, which is a mixture of rammed earth with concrete. Progressing into the post-digital era of earth architecture can be seen worldwide. Mudbrick construction can be mostly found in developing countries. Some examples are the Gando Teacher’s Housing by Kere Architecture in Burkina Faso and the Orthodox church of St. George by Wallmakers in India. They use the same methods as vernacular buildings but with the help of new technologies such as CSBE, which is compressed earth blocks. The great wall of WA by Luigi Rosselli in Australia is a 230m rammed earth wall on one side made of local earth and a sand dune on the other side. Enclosing the 12 residences provides them with the best thermal mass, making them cool in the subtropical climate. A project by Joly & Loiret in Paris by the name “Manufacture Sur Seine – Réinventer la terre”, reinventing the earth, has the idea of creating a large multi-purpose urban estate that will be made from rammed earth. The soil used will be the one extracted from the Paris metropolis during the new digging of the metropolitan rail network. Looking into earth architecture I would strongly argue that it’s worth starting construction with earth again. Rammed earth or mudbricks don’t only drastically cut down the embodied energy of a building, but also upcycle other industries' waste. Using soil from other industries and construction sites that would otherwise be considered as waste. As well as giving natural insulation and adding a passive solar factor to the building. This field of earth building is slowly picking up again, now that the climate crisis is accelerating. Now that this practice is reawaking it will soon flourish again in urban areas. As in the words of sociologist and philosopher Edgar Morin “the great movements of transformation always start in a marginal, deviant, modest or even invisible way”. The Anthropocene epoch of abusing the earth’s resources to construct short-lived architecture instead of investing in our future. So, on that note vernacular architecture, that is still around now for us to admire, lets not just admire them but actually learn from them and apply their ideologies into the modern pillars of good architecture. Bibliography Rodger, L., 2021. Climate change: The massive CO2 emitter you may not know about. BBC News David Oates, 1990. Innovations in Mud-Brick: Decorative and Structural Techniques in Ancient Mesopotamia. World Archeology, Taylor & Francis Ltd. Oliver Paul, Built to meet need: Culture issues in vernacular architecture, Architectural Press Luebering, J., 2021. pueblo architecture. Encyclopedia Britannica City Monitor. 2021. In Yemen, there's a city full of 500 year old skyscrapers made of mud - City Monitor Steele, J., 1988. Hassan Fathy. London: Academy Editions. Predock, A. and Collins, B., 2000. Antoine Predock houses. New York, NY: Rizzoli International Publications. Maniatidis, V. and Walker, P., 2008. Structural Capacity of Rammed Earth in Compression. Journal of Materials in Civil Engineering, pp.230-238. Walker, P., Keable, R., Martin, J. and Maniatidis, V., n.d. Rammed earth: design and construction guidelines. Kapfinger, O. and Rauch, M., 2001. Rammed earth. Basel: Birkhäuser. Agence Joly & Loiret. 2021. SEN1 (Manufacture sur Seine) - Agence Joly & Loiret.

The rise of technologies such as robotics and artificial intelligence have a substantial influence on our daily lifestyle with the transport sector being no exception. Fully autonomous vehicle (AV) technology networks are getting closer to reality with AV technology receiving both positive and sceptical criticism (Bagloee, et al., 2016). Companies such as Nissan, Tesla, Amazon, Uber, Google, etc. are all developing various levels of autonomy with Tesla and others widely achieving level 3 self-driving capabilities with autonomy levels being described in Figure 1 as per SAE J3016 Standards. As estimated by McKinsey, AVs implementation into the transport network will have a direct societal value between 0.2 to 1.9 trillion dollars annually by 2025 with the AVs being driving forces for the future economic model of cities and countries (McKinsey, 2013). Safety and crashes Autonomous vehicles aim is to improve the transportation sector by reducing crashes, energy consumption, pollution and congestion as well as increasing transport accessibility. As currently inevitable, accidents and human casualties in transportation networks is present, with 90% of car crashes blamed on human errors with the UK road deaths reported at 1,748 for 2019 (DfT, 2020). Studies suggested that if level 0 or 1 vehicle automation is implemented to all vehicles, a reduction of 1/3 of accidents could be achieved by equipping cars with adaptive headlights, forward collision warnings, lane departure warnings and blind-spot assistance (IIHS, 2010) (JS, 2011) (CM, 2008). Australian research went further to indicate that collision warnings technology could prevent 25-35% of serious crashes in Australia (Australian Government, 2017). Efficiency and productivity Congestion especially on motorways have obvious consequences of increased travel time, increased emitted pollution and increased chance of accidents (Bull, 2003). By increasing the use of AVs, productivity and efficiency of transport networks will improve by increasing average traffic speeds and by safely reducing distances between vehicles (Australian Government, 2017). This will significantly increase road capacity with studies estimating up to 5 times increase (Fernandes & Nunes, 2012). Furthermore, AVs will positively affect the reduction in traffic delays and stoppages from traffic incidence as well as encourage the use of public transport through low-cost, on-demand first and last-mile travel such as Uber services (Australian Government, 2017) (JM, et al., 2014). However, it should be argued that more comfortable and convenient travel of AV on-demand services may encourage a shift away from public transport. Moreover, AV technology connectivity features were found to provide an opportunity to mitigate congestion as found by Dresner and Stone (K & P, 2004). A reservation-based system designed for connected AVs can perform twice better as traffic lights since more congested traffic conditions could be handled more smoothly. As an advantage, AVs will provide alternatives to private vehicle ownership as well as give an opportunity for private transportation to those unable to drive, however, access to AV mobility may increase the number of trips made, which creates an additional demand to an already overloaded transportation network which is not desirable. However, AVs will remove the need for engaging physically with driving, allowing the passengers to utilise the travel time on other productive activities. Additionally, the logistics industry could be benefited in terms of applications of platooning which will improve traffic safety, reduce cost and fuel consumption due to reduced drag and increase the number of goods able to be transported on single freight trips (Australian Government, 2017) (ACEA, 2017). Public transport and private car ownership AV technologies can be a vital player in the development of future public transport networks. AVs can boost the use of driverless taxis and similar car-sharing schemes consequently providing more convenience for households with ownership of private vehicles being less favourable and more costly as illustrated by BCG which suggest AVs will lower by 30% the cost per passenger kilometre (BCG, 2020). Automated public transport services can deliver increased social benefits by providing new mobility options in areas not linked by public transport and also will provide reductions in the need for investments in new services and infrastructure required by future demand (Australian Government, 2017). As society moves away from vehicle ownership, annual fixed costs on maintenance and parking charges will be eliminated with the extensive use of AV car-sharing services. This will also remove the need for parking spaces in busy city centres which can free up space and provide areas for further urban growth. Nevertheless, the introduction of AVs will potentially deliver a positive societal impact by providing mobility to people with disabilities, older people and children who currently have difficulty accessing transport services in their community (Australian Government, 2017) (Bagloee, et al., 2016). However, to encourage the uptake of this technology, insurance of accessibility considerations is of paramount importance. Provision of wheelchair accessible AVs when human drivers are not present should be thoroughly evaluated. Environment With an efficiently programmed interconnected transport network, come benefits not only of social improvement but also environmental. Throughout the years regardless of AVs, the fuel consumption of vehicle engines has extensively improved subsequently, cutting customers fuelling costs and in parallel reducing the carbon emissions of vehicles reducing their environmental burden. The adoption of AV technology from even levels 1, 2 and 3 with features such as cruise control, graduate acceleration and deceleration is said to have an opportunity to optimise driving and enhance fuel economy by up to 10% (NRC, 2010). Platooning has shown both for freight and passenger that CO2e emissions can be reduced between 16-20% from the trailing vehicles and by up to 8% from the lead vehicle (ACEA, 2017)(Somers & Weeratunga, 2015). However, the environmental impacts of AVs will extensively depend on the extent of utilising low or zero-emission technologies such as electric or hydrogen. As discussed before, AVs have the potential to increase the frequency of trips made with a reduction of public transport use, with travel without passengers at certain times having wasteful mileage travelled with environmental impacts if non-net-zero vehicles are used. Autonomous vehicles are the future of transportation and the positives far exceeding the negatives however some features of the system should be done in collaboration with all the stakeholders to take full advantage of the social and environmental benefits AVs bring to mobility. REFERENCES McKinsey , 2013. Disruptive technologies: Advances that will transform life, business, and the global economy. s.l., McKinsey Global Institute. Bagloee, S. A., Tavana, M., Asadi, M. & Oliver, T., 2016. Autonomous vehicles: challenges, opportunities, and future. J. Mod. Transport. (2016) 24(4):, p. 284–303. SAE, 2019. SAE Standards News: J3016 automated-driving graphic update. [Online] Available at: https://www.sae.org/news/2019/01/sae-updates-j3016-automated-driving-graphic [Accessed 29 May 2021]. DfT, 2020. Statistical Release. [Online] Available at: https://iamwebsite.blob.core.windows.net/media/docs/default-source/press-releases/rrcgb-provisional-results-2019.pdf IIHS, 2010. New estimates of benefits of crash avoidance features on passenger vehicles. s.l.:Insurance institute for Highways JS, J., 2011. Crash avoidance potential of four passenger vehicle technologies. s.l.:Accid Anal Pre. CM, F., 2008. Crash avoidance potential of five vehicle technologies. s.l.:Traffic Injury Prevention. Australian Government, 2017. Social Impacts of Automation in Transport, s.l.: Department of Infrasructure and Regional Development . Fernandes, P. & Nunes, U., 2012. Platooning with IVC-enabled autonomous vehicles: strategies to mitigate communication delays, improve safety and traffic flow, s.l.: IEEE Trans Intell Transp Syst 13:91–106. JM, A. et al., 2014. Autonomous vehicle technology: A guide for policymakers, s.l.: Rand Corporation. Bull, A., 2003. TRAFFIC CONGESTION THE PROBLEM AND HOW TO DEAL WITH IT, Santiago: UNITED NATIONS PUBLICATION. K, D. & P, S., 2004. Multiagent traffic management: a reservation-based intersection control mechanism. pp530-537, In: Proceed- ings of the Third international joint conference on autonomous agents and multiagent systems. ACEA, 2017. What is Platooning. [Online] Available at: https://www.acea.be/uploads/publications/Platooning_roadmap.pdf [Accessed 13 May 2021]. BCG, 2020. Can Self-Driving Cars Stop the Urban Mobility Meltdown?. [Online] Available at: https://www.bcg.com/en-gb/publications/2020/how-autonomous-vehicles-can-benefit-urban-mobility [Accessed 2 May 2021]. NRC, 2010. Hidden costs of energy: unpriced conse- quences of energy production and use, s.l.: National Academies Press. doi: 10.17226/12794. Somers, A. & Weeratunga, K., 2015. Automated Vehicles: Are we ready?, s.l.: erth: Main Roads WA. Retrieved from.

The construction sector is one of the largest in the world economy, with about $10 trillion spent on construction-related goods and services every year 👉 Visit Structures Insider's homepage for more stories.👈 5. Skanska Stock price: SKA-B (STO) SEK 205.20 +0.70 (+0.34%) Headquarters: Stockholm, Sweden CEO: Anders Danielsson (1 Jan 2018–) Revenue: 145.4 billion SEK (2016) Latest Projects Skanska has agreed its biggest ever contract, as part of the team working on LaGuardia Airport’s Central Terminal B in New York. The value of the design/build contract amounts to a total of USD 4 billion, about SEK 33 billion and Skanska has a 70 per cent share (USD 2.8 billion, about SEK 23 billion). The amount will be equally divided between Skanska USA Building and Skanska USA Civil and included in the order bookings for the second quarter of 2016. 4. Hochtief Stock price: HOT (ETR) €106.00 -0.30 (-0.28%) 18 Oct, 17:35 CEST - Disclaimer Parent organization: ACS Group (66.5%) CEO: Marcelino Fernandez Verdes (Nov 2012–) Revenue: 22.63 billion EUR (2017) Latest Projects Twenty-four kilometres of the existing Gateway Motorway was upgraded and new sections of the motorway north of the bridges were constructed. The contract also included maintenance of the asset over a 10-year period. In 2010 the bridges were renamed the Sir Leo Hielscher Bridges. 3. Bechtel Headquarters: Reston, Virginia, United States Revenue: 25.9 billion USD (2017) Number of employees: 55,000 (2017) Founder: Warren A. Bechtel Latest Projects This five-year contract will see Bechtel partnering to manage the delivery of the £480 million City Airport Development Programme (CADP). The CADP includes: expanding the existing terminal by 24,500m2  and completely reconfiguring its internals and externals constructing a three-storey passenger pier creating eight new aircraft stands and constructing a new parallel aircraft taxiway. The expansion work will require working within King George V Dock where the project team has uncovered an unexploded ordnance from World War II. The upgrade will improve air traffic movements from 38 to 45 movements per hour and enable increased annual passenger movements from 4.5 to 6.5 million passengers by 2025. Additionally, the programme will help future-proof the airport to accommodate the next generation of aircraft that are quieter, have longer range and greater fuel efficiency 2. Grupo ACS Revenue: 34.06 billion EUR (2016) CEO: Florentino Pérez (1997–) Owner: Florentino Pérez (12.5%) Headquarters: Madrid, Spain Number of employees: 210,345 (2014) Subsidiary: Turner Construction Latest Projects The Alqueva Dam is an arch dam and the centrepiece of the Alqueva Multipurpose Project. It impounds the River Guadiana, on the border of Beja and Évora Districts in the south of Portugal. The dam takes its name from the town of Alqueva to its right bank. It creates a large reservoir with an inter-annual regulation capacity from which water may be distributed throughout the region. The dam was completed in 2002 and its reservoir reached the full level, for the first time, in 2010. The 518.4-megawatt (695,200 hp) power station was commissioned in two stages, stage I in 2004 and stage II in 2013. The Alqueva Dam constitutes one of the largest dams and artificial lakes (250 square kilometres (97 sq mi)) in Western Europe. 1. Vinci Stock price: DG (EPA) €96.54 -0.68 (-0.70%) 18 Oct, 17:37 CEST - Disclaimer Headquarters: Paris, France CEO: Xavier Huillard (2006–) Revenue: 43.52 billion EUR (2018) Subsidiaries: Eurovia, Cegelec, VINCI Concessions SA, MORE Latest Projects The New Safe Confinement will prevent the release of contaminated material from the present shelter and at the same time protect the structure from external impacts such as extreme weather. The construction of the huge structure happened offsite and slid into place to minimise the exposure to radiation. Read more... Read more : Top 5 Engineering Consulting Firms 2020

Here we have the conversation in the unbuttoned mood of a learned engineer with wide sympathies about his art, its history, its range, and the silly things which happen. It reads easily and has immense charm.--Architect's Journal It is really, really good if you want a primer on the structural design.--Elon Musk Rich and readable...personal, witty, and ironic.--Scientific American CHAPTER 1: The structures in our lives p18. Can engineers learn from natural structures? What can doctors and biologists and artists and archaeologists learn from engineers? p20. (the living structure) Trees are the most durable living structures (max height of 110 meters) p22.(the technological structure) Limitation of material resources made the engineer turn to technology which was the primary approach to solving this problem. p23. Pneumatic tire: (John Boyd Dunlop) A pneumatic, or air-filled, the tire is made of an airtight inner core filled with pressurized air. A tread, usually reinforced with steel belting or other materials, covers this inner core and provides the contact area with the road. John Boyd Dunlop p25. (structures and aesthetics) relating the appearance to the structure of their products. CHAPTER 2: Why structures carry a load p38. All materials and structures deflect, although to greatly varying extents, when they are loaded. CHAPTER 3: The invention of stress and strain p50. Hooke's law: properties of material & behavior of the structure. p52. E= Youngs Modulus = elastic modulus = stiffness - fundamental knowledge of stress and strain p55-56. The strength of a Structure is simply the load (N or kg) that will just break the structure. Known as breaking load. Strength of Material: is the stress (MN/m2) required to break a piece of the material itself. The object of many strength calculations is to predict the strength of a structure from the known strength of its material. CHAPTER 4: Designing for safety p66. Stress trajectories in a bar are uniformly loaded in tension with and without a crack. p68. Stress at the tip of the crack may well be a hundred or even a thousand times higher than the stress elsewhere in the material. CHAPTER 5: Strain energy and modern fracture mechanics p71. Information about local vs breaking stress p74. Every elastic material which is under stress contains strain energy, and it does not make much difference whether the stress is tensile or compressive. p92. The commonest arrangement to absorb energy is bending. To break any material in tension a crack must spread right across it. p94. The quantity of energy required to break a given cross-section of a material defines its toughness - fracture energy. CHAPTER 7: Joints, fastenings, and people P132-147 important pages. p133. The design of a structure is influenced much more by its stiffness than by its strength. Where the need is for rigidity rather than strength, the whole problem becomes very much easier and cheaper. p148. Creep : [definition] is why old shoes are more highly stressed than new ones. CHAPTER 8: Soft materials and living structures p151. emulsion [definition] : Two liquids can form different types of emulsions. An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable). p156. Arteries are under constant stress n strain. p158. In a cylindrical vessel (always) : longitudinal stress: p Circumferential stress: 2p p159. Poisson ration [definition] : elastic effect behavior. p161. Membranes stretch with no thickness deformation: constant stress. p171. Our ancestors generally avoided tension structures as far as they could and tried to use constructions in which everything was in compression. p174. What kept a building from tipping up and collapsing was not so much strength of the stones and mortar as the weight of the material acting in the right places. p181-183. Thrust line: The line of thrust is the locus of the points, through which forces pass in a retaining wall or an arch. It is the line, along which internal forces flow. In a stone structure, the line of thrust is a theoretical line that through the structure represents the path of the resultants of the compressive forces. For a structure to be stable, the line of thrust must lie entirely inside the structure p182. Oblique loading [definition]: the loading that deflects the thrust line in this kind of way. p184. Where there is a crack, there must once have been tension stress. walls, masonry dams usually fail not from lack of strength but from lack of stability. p186. Heavy masonry can be regarded as a structure that is ‘ pre-stressed’ conditions. p188. Definition of an Arch. p188-191. Useful information about arches. p192. Sealing up of structures (interesting to read) The square-cube law (or cube–square law) is a mathematical principle, applied in a variety of scientific fields, which describes the relationship between the volume and the surface area as a shape's size increases or decreases. It was first described in 1638 by Galileo Galilei in his Two New Sciences as the "...ratio of two volumes is greater than the ratio of their surfaces”. -unlike most other structures, buildings fail because they become unstable and tip-up. CHAPTER 10: Something about bridges p200. The facts of life are that the rise of the arch must be about half its span. p201. Cast iron is very brittle. It resembles stone in being strong in compression but weak and unreliable in tension, and so, in building construction, it has to be treated rather like masonry. p202. Vibrations of the trains would crack the brittle cast iron. p205. James Finlay: James Finlayson was a Scottish Quaker who, in effect, brought the Industrial Revolution to Tampere, Finland. p206. The cables of a suspension bridge take up the best shape automatically because a flexible rope has no choice but to comply with the resultant of all the loads which are pulling on it. p225. After all, how many house architects even talk to a naval architect? p231. A cantilever: ships masts, turbine blades, horns, teeth, animals necks, and trees p238. A cantilever truss will probably break mear its roots p239. Animal skeleton - shear bracing p242. Longitudinal stress increases as you move away from the neutral axis p245. Shear stress measures the tendency for one part of a solid to slide past the next bit or jerk the rug from under someone's feet or ankle twist. p249. A trellis (treillage) is an architectural structure, usually made from an open framework or lattice of interwoven or intersecting pieces of wood, bamboo, or metal that are normally made to support and display climbing plants, especially shrubs.t 5 p255. System of Applied Tension: in other words, by lacing. p256. Plastic propellers p257. Shear stress is only tension and compression acting at 45 degrees and vice versa. p258. In ductile materials both tension and compression, failure tends to occur by shear. (look diagrams above) p260. The wings of an aircraft are subject to bending forces, very much like a bridge. p264. Twisting or torsional deflection. p266. Torsional stiffness = no twist. p269. Torsion & twisting. p271. Torsion makes everything heavier on a design. (skiing=torsion) p272. Blackhole = massive compression force. p273. Compression = study of ways of getting out of tight places. p274. Compressive failure == 45degree shearing. p275. Brittle = has cracks. p277. Ductile failure in metals would be the same in compression and tension( by shearing). p280. Columns = trees (good columns in compression) p281. Pre-stressed tree in a calm..the outside of the trunk is in tension all around, the inside is in compression. p283. Keep concrete always in compression and don't allow it to go to tension when bending occurs, therefore no cracking in concrete is happening in pre-stressed beams. p293. Long-wave mode: buckle over all of its lengths, or short-wave: that is to say locally, by putting a sort of crease or crumple onto the wall of the tube. p294. Bamboo is a natural stiffener that uses stringers or ribs to stiffen up. P296 - 297. A sandwich-structured composite is a special class of composite materials that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high bending stiffness with overall low density. Open- and closed-cell-structured foams like polyethersulfone polyvinylchloride, and honeycombs are commonly used core materials. Sometimes, the honeycomb structure is filled with other foams for added strength. p303. “concept of design” p305. The cross-section of a tension bar is proportional to the load. p306. “ work of fracture falls dramatically with the increase of tensile strength” p310. Compound interest effect: Compounding: is the process in which an asset's earnings, from either capital gains or interest, are reinvested to generate additional earnings over time. This growth, calculated using exponential functions, occurs because the investment will generate earnings from both its initial principal and the accumulated earnings from preceding periods. p311. Meccano is a model construction system created in 1898 by Frank Hornby in Liverpool, United Kingdom. The system consists of reusable metal strips, plates, angle girders, wheels, axles and gears, and plastic parts that are connected using nuts and bolts. It enables the building of working models and mechanical devices. Monocoque: an aircraft or vehicle structure in which the chassis is integral with the body. p315. Dracone barge (photo above) p319. Energy intensity is a measure of the energy inefficiency of an economy. It is calculated as units of energy per unit of GDP. p321. E/p that is to say, the specific Youngs modulus which governs the weight-cost of the overall deflection. - Read Appendix 4. p324-325. Meaning of engineer: ‘the entire physical world is most properly regarded as a great energy system “ p330. A great deal of the strength-predicting elements of design boils down to a sort of game in which we try to spot the weakest link in a load-bearing system. p333. [definition] Fatigue = fluctuating loads. p337. Fuselage [picture below] p350. Interesting read about aerodynamics p355. Architecture vs civil engineer ( efficiency vs aesthetics ) p359. Emotional with the design - subconscious mind - the imprint of the character. p364. Philistinism engineers are all about: In the fields of philosophy and æsthetics, the derogatory term philistinism describes the 'manners, habits, and character' of a person whose anti-intellectual social attitude undervalues and despises art and beauty, spirituality and intellect. p366 - 367. “ modern technology gets more and more functional, we can less and less bear to look at it.” “ an ugly ship is no more attractive than an ugly woman - however fast she may be” p369. Doric architecture: The Doric order is characterized by a plain, unadorned column capital and a column that rests directly on the stylobate of the temple without a base. The Doric entablature includes a frieze composed of triglyphs—vertical plaques with three divisions—and metopes Appendix A - the process of design. You can get the book here: *Affiliate links included

The Approval In Principle (AIP) document outlines the concept for the design of the structure. This will be used for most highway structures and incorporates the Technical Approval Schedule (TAS) which lists all the current British Standards and documents that are relevant to the design of highway structures. According to BD2/12 (Document: Design Manual For Roads And Bridges (DMRB) ): volume 1 - SECTION 1 - PART 1 - BD 2/12 HIGHWAY STRUCTURES: APPROVAL PROCEDURES AND GENERAL DESIGN APPROVAL PROCEDURES Summary of what an AIP is An AIP is a standard documentation required for any structure (e.g. Bridge, retaining wall, gantry, etc.) constructed in the civil engineering industry. This document will include: A description of the proposed structure The category of the structure Details of the road it is on or adjacent to The proposed loading criteria The proposed method of analysis of the structure A schedule of applicable design standards Requirements for road restraint systems (parapets and safety fences) Headroom requirements Details of other structural forms considered Conceptual drawings (if applicable) Details of any references from Standards and any other information required by the Technical Approval Authority to determine whether the proposed design and checking regime are robust and acceptable. In theory, prior to commencing design, the AIP must be signed by the Technical Approval Authority. In practice, program constraints dictate that some design is carried out prior to obtaining a signed AIP, though this is at the designer/client's risk as the Technical Approval authority could require a change to the design process, resulting in the need to revisit the design. The History of the AiP In the early 1970s, failures at Yarra (Australia), Milford Haven (Pembrokeshire, Wales), Koblenz (Germany), and over the Danube (Austria) occurred during erection. Read more: West Gate Bridge collapse - Yarra (Australia) Around 11.00 am that morning the Section Engineer contacted Jack Hindshaw, the Resident Engineer, and advised that things were not going well. Thirty-five construction workers were killed and 18 injured... Read More... Resulting from these failures and the subsequent Report of the Merrison Committee, the following important changes were made by the then Ministry of Transport: (i) The Department would continue to examine design criteria and methods but not computations. (ii) The requirements by the Department for a certificate of independent check of the design and computations. (iii) The application of Approval in Principle (AIP) stage to all but minor structures, which would cover the selection of bridge type, the materials for its construction, and methods of analysis and design to be adopted. Technical Approval (BD2/12 - 2.26) The Designer must provide sufficient information to enable the TAA to carry out the following aspects, where applicable: (i) Appraise the proposed design or assessment criteria, principles and methods. (ii) Agree on the required working life for the structure and its main components. (iii) Agree on the Category of the Proposals. (iv) Ensure consideration has been given to any special studies concerning safety and risk assessment and management that have a bearing on the final design or assessment or the construction process. (v) Be satisfied that adequate consideration has been given to safety, sustainability, buildability, traffic management, environmental impact, aesthetics, structure robustness, durability, maintainability, access and inspection, upgradeability, whole life costs, demolition and compliance with the Overseeing Organisation’s requirements. (vi) Agree on the list of documents included in the TAS and Departures. (vii) Appraise the geotechnical conditions and other relevant investigations. (viii) Appraise the adequacy of existing records and investigation data and the need for further investigations or studies that have a significant bearing on the preliminary or final design, assessment, execution, operation, maintenance or demolition processes. (ix) Review the adequacy of consultation with other stakeholders and the incorporation of agreed requirements. (x) Agree proposed Category 3 Checker based on their relevant experience and competence. (xi) Resolve any point(s) of difference between the Designer or Assessor and the Checker. Share your content with us! Join the SI Writers Platform now Submit your work 📝 and get featured 📌 on our website 💥 Checking Procedure (BD2/12 - 2.32) Assessments, designs, and drawings, together with bar bending schedules, must be checked as follows: Structures, which conform in all aspects of design, assessment, and execution to DMRB and MCHW Standards and contain no Departures, provided they also conform to one of the following: Category 0 and 1 Structures (a) Categories 0 and 1 require an independent check by another engineer who may be from the Design/Assessment Team. 3.4.1 Category 0: (a) Single span simply supported structures with a span of less than 5m. (b) Buried concrete boxes, buried rigid pipes, and corrugated steel buried structures of less than 3m clear span/diameter and having more than 1m cover. (c) Multi-cell buried structures, where the cumulative span is less than 5m, and having more than 1m cover. (d) Earth retaining structures with an effective retained height of greater than 1.5m (1.0m or greater in Northern Ireland) but less than 2m. (e) Minor structures within the scope of BD 94 (DMRB 2.2.1) and not situated at a very exposed site as defined in BD 94. (f) High masts ≤25m and not situated at a very exposed site as defined in BD 94. 3.4.2 Category 1: (a) Structures with a single simply supported span of 5m or greater but less than 20m and having less than 25° skew. (b) Buried concrete boxes, buried rigid pipes, and corrugated steel buried structures with a clear span/diameter of 8m or less. (c) Earth retaining structures with an effective retained height of 2m or greater but less than 7m. (d) Minor structures outside the scope of BD 94 (DMRB 2.2.1) or situated at a very exposed site as defined in BD 94. (e) High masts >25m or situated at a very exposed site as defined in BD 94. (f) Environmental barriers 3m or more in height or with overhangs. (g) Portal and cantilever sign and/or signal gantries with a span of less than 20m. Category 2 Structures (b) Category 2 requires a check by a Check Team, which may be from the same organisation but must be independent of the Design/Assessment Team. Structures, not within the parameters of Categories 0, 1 or 3. Category 3 Structures (c) Category 3 requires a check to be carried out by a Check Team from a separate organisation proposed by the Designer or Assessor and agreed by the TAA. Complex structures, which require sophisticated analysis or with any one of the following features: (a) High structural redundancy. (b) Unconventional, novel or esoteric design aspects. (c) Any span exceeding 50m. (d) Skew exceeding 45o. (e) Difficult foundation problems. (f) Moveable bridges. (g) Moveable inspection access gantries, gantry rail and gantry support systems. (h) Bridges with suspension systems. (i) Steel orthotropic decks. (j) Internal grouted duct form of post-tensioned concrete structures. (k) Earth retaining structures with an effective retained height of 14m or greater. (l) Rock anchorages (Wales only). Sources: BD2/12, www.sabre-roads.org.uk Read more: