SFRC Overview Fibre-reinforced concrete is a composite material comprised of traditional concrete and steel fibres (look picture below). Normal unreinforced concrete is brittle with a low to not existing tensile strength and strain capacity. Steel fibres increase durability and ductility of the concrete mix as well as decrease installation and labour cost. Slender structures such as CMG Headquarters in Beijing could be achieved. 👉 Visit Structures Insider's homepage for more stories.👈 History of SFRC The concept of using fibres as reinforcement is not new. Fibres have been used as reinforcement since ancient times. Historically, horsehair was used in mortar and straw in mudbricks. In the 1900s, asbestos fibres were used in concrete. In the 1950s, the concept of composite materials came into being and fibre-reinforced concrete was one of the topics of interest. Once the health risks associated with asbestos were discovered, there was a need to find a replacement for the substance in concrete and other building materials. "There is strong evidence of asbestos leading cancers of the lung, larynx and ovaries," comments Ruban Selvanayagam of property renovation / buying company from the UK. By the 1960s, steel, glass (GFRC), and synthetic (such as polypropylene) fibres were used in concrete. Research into new fibre-reinforced concretes continues today. A QUICK video explaining Steel Fibre Reinforced Concrete (SFRC). Courtesy of Tyler Ley Advantages of Steel Fibres in Concrete ● The increased load-bearing capacity of concrete ● Reduction of concrete slab thickness ● Load capacity is not diminished by concrete cracks (crack control) ● Increased durability ● Low maintenance costs – extended service life ● Improved flexural properties ● Reduced absorption of water, chemicals, etc. ● Can be used on the fast track schedule. ● Easier positioning of joints (fewer joints required) ● Reduced site labour for managing steel reinforcement ● Reduced project costs – ensures economical designs ● Increased impact and abrasion resistance ● Even distribution of fibres throughout the concrete (concrete tensile strength can be specified) ● Tougher surface with fewer bleed holes (improved concrete quality expected) ● Savings will be greater for heavier crack control systems You May Also Like: The difference between Buckling, Compression & Shear Slender structural members loaded axially in compression will experience buckling. A relatively slender compression member (e.g. a column) may deflect laterally and fail by bending rather than failing by direct compression. The behaviour can be demonstrated by... Read more ● No requirement for heavy lifts of rebar and labour requirements. Reinforcement is incorporated in the mix. ● Corrosion-free surface finish. ● Reduces permeability of concrete (because micro-cracks are controlled). ● No deformation of corner castings. Disadvantages of Steel Fibres in Concrete ● No Eurocode Standards yet addressed for steel fibre reinforcement Design processes. However individual National Annex of some countries may provide some guidelines regards design suggestions. ● More expensive than traditional rebar. Can’t be used in heavy loadings situations – rebar is preferred. ● May require manufacturer license for batching this type of concrete mixes. ● Labour workers may require training. USES of SFRC a. Structural Applications (Buildings and Highways) - Steel decks. - Pile-supported floors. - Power-station floor slabs - The opportunity of pre-fabricated slabs manufactured at the factory and brought on-site for installation. - Use with rebar reinforcement increasing strength using less rebar. - Flat pavements. - Existing columns strength reinforcement. Essential Books for Civil Engineering Students Amazon's Choice b. Underground concrete structures - Tunnel linings reinforcement. - Potential Pile material. Leading Supplier in the Market They provide next level concrete performance steel fibres used fro SFRC For the full product click here: Dramix® steel fiber concrete reinforcement Sources: Wikipedia, www.bekaert.com , 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

Architectural Insight One of the most recognizable tourist attractions of the world, located in Rome🇮🇹, the Colosseum. Built between 72 A.D and 80 A.D under Emperor Vespasian, it was made from stone and concrete. More than 100,000 cubic meters of travertine stone was used for the outer wall of the Colosseum which was set without mortar held together by 300 tons of iron clamps. The final façade was estimated at 100,000 cubic meters of marble that in later years some of the marble was used for the construction of St. Peter’s Basilica. 👉 Visit Structures Insider's homepage for more stories.👈 Being the largest amphitheatre in the world, the Colosseum has 80 entrances and could seat approximately 50,000 spectators. For the protection of these spectators from the blistering sun and heat of Ancient Rome, there was the velarium an awning that could be pulled over the top of the seating area providing shade. Below this marvellous structure, located numerous rooms and underground passages where animals and the gladiators were kept. There were also 36 trap doors in the arena for special effects! Not only being a mean of free entertainment for the people of Rome, but it was also a political tool to gain the trust of the people by sometimes giving out free food to the spectators. It's said that for the hundreds of years that the games were played, the Colosseum has taken the lives of about 50,000 people and over a million wild animals. Read more: 5 books you NEED to own if you are a 1st-year civil engineering student What's the most impressive ancient structure in the world? Concrete variable radius arch dam explained New York City is planning to expand Manhattan into East River to battle climate change

by Merkur Alibali Wood vs Steel Wood buildings are lighter and less expensive to build. Based on current building codes wood structures are not more ductile than steel structures however their mass being lighter attracts less seismic load for the same ground motion than a typical steel structure. (Seismic force is related to mass and ground acceleration and some other inherent building dynamic parameters). The mass factor alone can be its claim to being better in seismic-prone regions. Additionally, wood framing labor is considerably cheaper than steel framing which would require highly trained, union-based, erectors and welders working under strict schedules and safety protocol. Wood framing can be performed by anyone who’s been on the job no more than a month under proper supervision. The typical building wood structure in California is what you would characterize as “wall stud framing”. The seismic resistance is provided primarily by plywood shear walls. Sometimes steel frames are added (Special Moment Frames) or Masonry Shear Walls. Structures built up to the 60s combined all kinds of systems. Afterward, the trend became in not mixing the seismic force-resisting systems (SFRS) much. The steel structures are typically columns, beams, and girders with composite concrete metal decks. The SFRS is provided by a medley of systems, BRBF (Buckling Restrained Braced Frames, SCBF (Special Concentric Braced Frames), SMF (Special Moment Resisting Frames). In some cases Masonry shear walls (or even Concrete shear walls). Each provides benefits and drawbacks however the steel system’s ductility is beyond what can be achieved from a well-detailed wood building. The benefit of steel structures is that they permit the achievement of the architect's vision in a way that is more economical than say concrete or wood construction. Each material offers its benefits but personally, I would much rather be in a wood building than a steel building during an earthquake. Having witnessed seismic tests on a shake table performed on a wood building I can attest to their resilience even after the failure of the seismic resisting system. Also for you : The difference between Buckling, Compression & Shear

by Sherif Issa I am sure you’ll get a lot of answers to the very same question. Some will be driven by personal opinion, some by an objective, scientific view; and some driven by sheer patriotism. Why so? How so? .. Because there is always a talented architect in every country and every culture. Think of these examples… The US? — You have Frank Lloyd Wright [of course] with his Guggenheim museum Brazil — I loved Lúcio Costa’s persona as well as his work… India?—- Bangladesh and Pakistan? There are so many of them Iraq?—- Zaha Hadid with her super eccentric designs. Italy and France? —- these countries wrote the book on art and architecture. How about Egypt? — Yes sir, we have the multi-talented good man who had sustainability in his mind long, long before it was a buzzword... Mr. Hassan Fathy with his concept of “Architecture for the poor” Fathy has developed systems of natural ventilation and air conditioning in his buildings that were almost as good as our modern HVAC but more efficient and planet-friendly since they consumed no energy at all. He is considered by some as one of the greatest contemporary architects we have. Some people go far enough to consider him an owner of a “thought school’, not just a good architect. So, there you have it. Your “mirror on the wall, greatest architect of them all” answer.

Introduction Banister’s sustainable mobility paradigm published in 2007 is a very influential paper with stated principles being realised and implemented in the following years after publication. The paper exploits two fundamental principles, the first principle being the approach of considering travel as a derived demand and not as an activity people wish to take and secondly the correlated understanding that, travel cost and time are taken to travel is the main reason for people to minimise their generalised costs of travel. Banister defined four key actions within a sustainable mobility approach being as substitution, modal shift, distance reduction and efficiency increase with the aim of reducing the need for travel, reducing the trip lengths and encourage the efficient use of transport system. 1. Reducing the need to travel—substitution Life cycleways of thinking encourage the first question asked being of the need of creating or executing the project or service at hand. In transport, a trip is no longer required to be made from the time when the activity has been executed without the need for travel. By means of technology and the power of telecommunication and the internet, tasks such as grocery shopping and working can be achieved from the comfort of homes. Due to the COVID-19 pandemic, the US eCommerce market saw a 78% increase from May 2019 to May 2020 on the online shopping sales amending the lockdown measures being placed (Avinash Unnikrishnan, 2020). The current pandemic had a major impact on rethinking travel patterns and general adaptation to virus-free transportation. 2. Transport policy measures—modal shift The aim of reducing the use of cars could have many social, economic, and environmental benefits. As per Banisters, incorporating transport policies with the aim to reduce the number of cars used and slow down traffic in conjected areas in an urban setting will make more effective use of the available spaces and improve the welfare of its citizens. Streets should stop being only considered as roads but also as spaces for people, green modes and public transport (Banister, 2007). London leaders started the initiative back in 2008 by introducing Low Emission Zone (LEZ) and then followed in 2019 introducing the world’s first Ultra Low Emission Zone (ULEZ) in areas of central London, fully imitating concepts predicted by Banister by reducing the car movements on roads (London, 2019). Data finds that a 65% reduction of older, more polluting, non-compliant vehicles were detected in these zones between 2017 and 2019 which had the reaction of reducing harmful NOx emissions from road transport in the central zone by 31% (200 tonnes) making roads less conjected and improving the welfare of its citizens. 3. Land-use policy measures—distance reduction To achieve the carbon net-zero goals set by governments around the world a switch to green modes of transport will be of paramount importance. Only in the UK transport-related CO2e emissions are the highest with a 27% share as seen in Figure below (BEIS, 2021). In his paper, Banister drew attention to the need to find physical means by which distance can be reduced in an urban setting (Banister, 2007). This can be achieved by switching to green modes of transport and by applying public policies through the development of increasing densities and concentration of housing, through the design of buildings, public spaces and transport routes giving emphasise on car-free developments. Establishing size thresholds of the availability of services and facilities (Banister, 2007) has been a fundamental aspect of the 15-minute city which may be defined as ideal geography where most human needs and many desires are located within a travel distance of 15 minutes (ANDRES DUANY, 2021). 4. Technological innovation—efficiency increase Technology plays a vital role in improving people’s quality of life and its impact on transport efficiency is substantial. Banister views that to achieve sustainable mobility the best available technology in terms of car engine design, alternative fuels, and use of renewable energy should be implemented. Introduced standards and regulations can reduce levels of noise and pollution at certain parts of a city, hence improving welfare. Banister extremely accurately anticipated the current London ULEZ zones (London, 2019) as he referred to the benefits of ensuring the access to certain parts of the city should be restricted to those vehicles that are seen to be environmentally cleaner than other vehicles (Banister, 2007). Recent technologies such as autonomous/electric vehicles and the hyperloop support the standards introduced by Banister such as reducing noise levels and decarbonizing the transportation system by reducing pollution. In conclusion, Banister's ideas are appropriate, however, further thinking into decarbonizing the energy power grid of nations should be incorporated in talks of achieving sustainable mobility. The key in my opinion to achieve this is collaboration and cooperation from all the industries participating in the transport market for the sole purpose of improving systems and implementing radical change promoting sustainability. About Professor David Banister David Banister is a Professor of Transport Studies at the Oxford University Centre for the Environment. Until recently he was Professor of Transport Planning at University College London. He has also been Research Fellow at the Warren Centre in the University of Sydney (2001-2002) on the Sustainable Transport for a Sustainable City project and was Visiting VSB Professor at the Tinbergen Institute in Amsterdam (1994-1997). He will be a visiting Professor at the University of Bodenkultur in Vienna in 2007. He is a Trustee of the Civic Trust and Chair of their Policy Committee (2005-2009) Useful Documents Banister, D., 2007. The sustainable mobility paradigm. Transport Policy 15 (2008) 73–80 , 19 November, pp. 73-80.

Smart motorways throughout England as defined by Highways England, have the objective to deliver more efficient motorways through the application of smart infrastructure technologies to improve real-time management of major motorways, including actively managing traffic, improving journey times and reliability, increasing capacity, reducing congestion, and maintaining safety levels (Arcadis, 2017). There are three main types of smart motorways, each having a slightly different way of operations (AA, 2020). Firstly, the controlled motorway has variable speed limits and a hard shoulder for emergency use. Dynamic hard shoulder motorways have a hard shoulder that could be opened up to traffic in congested periods as well it has gantry overhead signs indicating when driving is allowed on the hard shoulder. Furthermore, the all-lane running system has no hard shoulder with emergency refuge areas located approximately every 2.5km or 1.6km (Jallow, 2019). A Guerrieri comparison of a 1-km long section of conventional and smart motorway found that the highest environmental impact during a motorway life cycle is always due to vehicle emissions and specifically of platooning vehicles (Guerrieri, 2020). As the main goal of smart motorways is to improve the flow of traffic, this will have a big influence on the increase of the use of cars since capacities increase and the mode becomes more desirable by users with the effect of increasing carbon emissions. Someone could argue that improving the flow of traffic will reduce the number of times vehicles' engines are running hence reducing the environmental burden simultaneously, as reducing congestions and improving user’s experience. Recommended : Four key actions within a sustainable mobility approach as defined by Banister Others may argue that improving the capacity and flow of motorways and not promoting investments in other public transports, increases the number of cars, hence increasing emissions and negatively impacting air quality of the surrounding areas. The decarbonization of transport is mostly a challenge of energy rather than mobility. In the research paper “How to decarbonize the transport sector?” Zwaan stresses that a radical change in the automotive industry should occur with hydrogen becoming the dominant transport fuel for achieving a net-zero transport network (Zwaan, 2013). REFERENCES Arcadis, C., 2017. Smart Motorways Programme M6 J2 – J4 Environmental Study Report: Volume 1. [Online] Available at: https://assets.highwaysengland.co.uk/roads/road-projects/m6+junction+2+to+4+smart+motorway/Environmental+Study+Report+Figures+(Volume+1).pdf [Accessed 5 March 2021]. AA, 2020. Smart Motorways: Just how smart are smart motorways?. [Online] Available at: https://www.theaa.com/driving-advice/smart-motorways#:~:text=There%20are%203%20different%20types,in%20a%20slightly%20different%20way. [Accessed 8 March 2021]. Guerrieri, 2020. Smart vs conventional motorways: Environmental impact assessment under realistic traffic conditions. Elsevier. Jallow, H., 2019. The Concept of Smart Motorways. s.l., 2019 3rd International Conference on Smart Grid and Smart Cities (ICSGSC). London, M. o., 2019. CENTRAL LONDON ULTRA LOW EMISSION ZONE – SIX MONTH REPORT, London: Greater London Authority. Zwaan, B. d., 2013. How to decarbonize the transport sector?. [Online] Available at: https://www.sciencedirect.com/science/article/abs/pii/S0301421513004734 [Accessed March 2021].

The ultimate goal of humanitarian logistics (HL) is to deliver the right supplies in the right quantities to the right location at the right time to save lives and reduce human casualties (Balcik & Beamon, 2008). With an overall annual expenditure of around $20 billion, it’s still not enough to cover the unpredictable natural catastrophes (Tatham & Christopher, 2018). Major disasters such as the 2004 Thailand tsunami and the 2010 Haiti earthquake which had a substantial number of human casualties and infrastructure damage have emphasized the big importance of having efficient and effective humanitarian relief operations. Challenges Humanitarian logistics studies identify multiple challenges including, collaboration and coordination (Balcik, 2010), contextual factors related to unpredictability (Kovács & Spens, 2009), lack of resources (Gustavsson, 2003) and lack of planning (Jahre, 2016) as well as related to funding, accountability and even sustainability. A study conducted by interviewing UNHCR logistics field staff located in 130 countries, found that the main influence logistics challenge was that the internal structure, as well as its strategies and policies, influence both the nature of these operational challenges and the way in which it responds (Tatham & Christopher, 2018). Operational challenges such as inadequate infrastructure, security concerns, poor emergency response preparedness (ERP), coordination, lack of transparency between intra-organizational departments, and the lack of inadequate information sharing were identified. Furthermore, more field-related challenges were given of operating in uncertain and harsh conditions to find adequate resources such as durable vehicles and functioning generators. As transportation goal is to ensure that the right goods are delivered at the right place, at the right time, in the right condition it is stressed that cross-functional communication and coordination are essential to achieve seamless supply chain processes. Also, of challenges responded were the difficult access to beneficiaries, international transportation, and custom-related issues as well as infrastructure problems due to road network low quality (Tatham & Christopher, 2018). Moreover, a study completed by (Roh, et al., 2016) looked at challenges with pre-positioned warehouses identified challenges such as high asset maintenance cost, high inventory cost, failure in forecasting stock level, difficulties in justifying funding, IT breakdown, poor quality of goods, untrained local staff and limited space available in warehouses. Overall, the lack of time and resources for planning was one of the primary causes that negatively affect the activities and results HL tries to achieve which results in the difficulty to deliver relief in the right places with speed and accuracy. Solution Modern technology can provide a lot of advances in HL delivery. Technologies such as 3D printing, remotely piloted aircraft systems (RPAS), hybrid cargo ships, helium-filled airships each wish to improve the HL and deliver the relief faster and more efficiently. 3D printers (3DP) have the advantage of low cost ($40/kg) and ease of transportation that can utilize a range of source materials that can be used to build objects such as pipes and connectors used in water that can replace broken components. Moreover, 3DP will increase the transportation efficiency by reducing time and space as parts can be constructed on-site of the disasters within a timeframe up to 12 hours. An example of the 2010 Haiti post-earthquake debris removal which was estimated at 1000 trucks (Booth, 2010), could lead to onsite development of new 3D dwellings with a significant reduction in cost. RPAS, have the potential to transfer medical payload (Papua New Guinea,2014; Malawi,2016), provide post-disaster mapping (The Philippines, 2013; Nepal, 2015) and damage assessment of logistic routes and infrastructure (Vanuatu,2015) as well as act as a temporary mobile communications system. Another solution of hybrid cargo ships and helium-filled airships can lift significant quantities of material and deliver the last mile directly to affected areas by landing on water and docks if the infrastructure is damaged. These solutions eliminate the movements associated with loading/unloading hence saving time and cost at the various nodes (Tatham & Christopher, 2018). REFERENCES Balcik, B. & Beamon, B., 2008. Facility location in humanitarian relief. International Journal of Logistics: Research and Application, s.l.: pp.101–121. Tatham, P. & Christopher, M., 2018. Humanitarian Logistics : Meeting the Challenge of Preparing for and Responding to Disasters. s.l.:Kogan Page, Limited. Balcik, B. B. B. K. C. M. K. a. R. M., 2010. Coordination in humanitarian relief chains: Practices, challenges and opportunities. International Journal of Production Economics , pp. 126 (1), pp 22– 34 Kovács, G. & Spens, K., 2009. Identifying challenges in humanitarian logistics. International Journal of Physical Distribution & Logistics Management , pp. 39 (6), pp 506– 28. Gustavsson, L., 2003. Humanitarian logistics: Context and challenges. Forced Migration Review, pp. 18 (6), pp 6– 8. Jahre, M. P. A. a. V. W., 2016. Defining logistics preparedness: A framework and research agenda. Journal of Humanitarian Logistics and Supply Chain Management , pp. 6 (3), pp 372– 98. Roh, S., Kwak, D.-W., Beresford, A. & Pettit, S., 2016. CHALLENGES IN HUMANITARIAN LOGISTICS MANAGEMENT: AN EMPIRICAL STUDY ON PRE-POSITIONED WAREHOUSES, s.l.: s.n. Booth, W., 2010. Haiti faces colossal and costly clean-up before it can rebuild, s.l.: Washington Post Foreign Service.

With new technologies always comes the scrutiny of requirements of new laws and ethical consideration towards the brought society. Many ethical issues are encountered when considering how AVs are to be programmed in an event of actions taken in an accident situation. The safety potential of AVs had struck the discussion about whether non-autonomous driving should be banned for safety reasons when a level of safe and reliable autonomous technology is achieved (Nyholm & Smids, 2016). AVs driving systems may have a large advantage over human drivers in avoiding crash situations before they occur due to the constant 360 degrees of monitoring of the environment eliminating human errors. However, AV technology has still a lot of requirements of technology improvement and legal considerations nevertheless of Tesla and Waymo already bringing level 3 and 5 autonomous vehicles into the market. Several ethical guidelines and best practice documents are established to assist programmers in developing ethically-sound crash algorithms however these guides have been criticized as too vague and incoherent (Ryan, 2019). A hypothetical scenario known as the ‘trolley problem’, which considers the ethical dilemmas of whether to sacrifice one person to save a larger number is one of the biggest challenges AV programmers face when developing the crash response of their autonomous technology. It can be certainly proved that an AI algorithm with a vehicle braking system optimized with thousand real-time data points is far superior to a human reaction time as seen in early test vehicle programming by Google in 2015 (Gibbs, 2015). Nevertheless, an AV has many dilemmas of formulations of hypothetical situations whether the vehicle should prioritize the safety of its occupants over pedestrians in a crash situation. Of course, very few people would buy a car that prioritises the lives of others over the vehicle driver and passenger, but if they aim to protect the driver they may crash into children or light vehicles (Contissa, et al., 2017). On the other hand, as mentioned by De Sio, if safety is prioritised, in a similar crash situation the AI of the vehicle may hit a motorcyclist wearing a helmet, opposed to one without one because they would be more likely to survive (De Sio, 2017). This may lead to a chain reaction of people start to take unsafe activities in order to become safe due to knowing the response of the AVs algorithm, with an example being of not wearing a helmet thus avoiding collisions in possible accident situations. Analysts’ solution for this matter suggests that crash-optimization should be implemented because some crashes would be unavoidable (Lin, 2015) with algorithms based on vehicles decisions on least-likely determinable harm done in a situation (Ryan, 2019). Given that government regulations in regards to AV algorithms decision-making lack in clarity, it is likely that vehicle manufacturers will control and regulate this section of the market. A recent action of the US Department of transportation draft about Automated Vehicle Policy (Transportation, 2016) suggest that AV manufactures address ethical issues in a transparent and conscious manner with inputs from other stakeholders. However as argued by (Ryan, 2019), programmed responses remove control from the human being in driving circumstances and removes the choice and ability to make decisions in the vehicle’s navigation. These statements are directly associated with concepts threatening free will and moral responsibility which are being replaced by algorithms and AI of AVs developed by private entities (CNIL, 2018). Another issue arising with AVs is the topic of insurance and privacy. As AVs will be able to store an array of driver’s data such as habits, patterns and behavior insurance could be tailored to individual performances hence providing higher premiums to safer more conscious drivers. Conversely, a large amount of data will be collected which could infringe personal privacy and data security which could be subject to negative consequences of hackers stealing the data or on the other hand, a positive consequence could be the allowance of police accessing this information to reduce crime. An approach currently promoted is the DRIC “data remains in-car” which attempts to process data within the vehicles rather than transmit to third parties (CNIL, 2018) however, it should be pointed out that technical challenges are present to implement this type of technology. REFERENCE De Sio, F. S., 2017. Killing by autonomous vehicles and the legal doctrine of necessity, p425: Ethical The- ory and Moral Practice. CNIL, 2018. Connected vehicles: A compliance package for a responsible use of data.. [Online] Available at: https://www.cnil.fr/en/connected-vehicles-compliance-package-responsible-use-data [Accessed 29 May 2021]. Contissa, G., Lagioia, F. & Sartor, G., 2017. The ethical knob: Ethically-customisable automated vehicles and the law, s.l.: Artificial Intelligence and Law. Ryan, M., 2019. The Future of Transportation: Ethical, Legal, Social and Economic Impacts of Self‐driving Vehicles in the Year 2025, s.l.: Science and Engineering Ethics (2020) 26:1185–1208 Transportation, U. D. o., 2016. Federal Automated Vehicles Policy: Accelerating the Next Revolution In Roadway Safety, s.l.: s.n. Lin, P., 2015. Why Ethics Matters for Autonomous Cars. , s.l.: Autonomes Fahren: Technische, rechtliche und gesellschaftliche Aspekte (pp. 69-85). SpringerLink. Gibbs, S., 2015. The Guardian. [Online] Available at: https://www.theguardian.com/technology/2014/may/28/google-self-driving-car-how-does-it-work Nyholm, S. & Smids, J., 2016. The ethics of accident-algorithms for self-driving cars: An applied trol- ley problem? Ethical Theory and Moral Practice, s.l.: s.n.

#Amazon #UPS #DHL Logistics emissions data Logistics are regarded as a key determinant of a company’s performance, through the efficiency of supply chain systems and the calculation of the profitability of product sales. The calculation of profitability in the majority of logistics history has included only economic performance (McKinnon, et al., 2015), however, in recent years due to globalization and digitalization, wider environmental and social impacts are of large importance for green marketing and future strategy of supply chain providers. Green logistics are now regarded as good business practice as it provides a lot of opportunities for having a positive impact on financial and operational metrics without the need to trade off economic costs against environmental benefits. As stated in the SFC Annual report (SFC, 2020), freight transportation generates 8% of global CO2e emission and as much as 11% if logistics sites are also considered. Sustainable reforms of the sector are required as between now and 2050 the world will see a doubling in freight emissions, according to the International Transport Forum. Different modes of transport of freights are used based on the distance and time of the delivery requirement. Figure 1 and Figure 2 show the data of CO2e emissions of UK and the logistics provider DHL which both suggest that air transportation accounts for the majority of the emissions also justified due to usage of jet fuel and damping of greenhouse gases (GHG) emission at high altitudes which increases the quantity of the global warming potential (GWP) impact in the atmosphere (Sathaye, 2006). Mitigation of logistics systems environmental impact A four-step roadmap developed by the SFC as outlined in Figure 3 identifies the importance of calculating emissions across the multi-modal supply chain as well as setting targets on emissions reduction and the requirement of implementing new technological solutions as well as the need for collaboration across the industry. Collaboration of businesses, governments, research, and civil society should be achieved for a sector transformation to be realized. As defined by (Sathaye, 2006) and shown in Table 1 teaching, four solution types were identified of impact reduction, emissions reduction, changing operations, and economic and societal development considerations for making supply chains greener. Impact reduction To achieve greener supply chains and a substantial reduction of environmental impact, the focus should be given to the reduction of the environmental externalities impact associated with freight operations rather than the cause of the exhaust emissions level. An example of focusing on the effect rather than the cause could be illustrated by the introduction of the Low Emission Zone (LEZ) and Ultra Low Emission Zone (ULEZ) in areas of central London, which reduces the car movements on roads including high emission freight vehicles (London, 2019). A reduction of 31% (200 tCO2e) harmful NOx emissions from road transport in the central zone have been recorded, improving the welfare of its citizens and subsequently challenging supply chains to adapt to these government regulations. To achieve emissions reductions of logistics systems valid quantification measures of impacts are required such as the intake fraction (Marshall, et al., 2005), which calculates the ratio of the quantity of pollutant intake by people over the total emissions. Aligned with the sustainable logistics roadmap of SFC (see Figure 3), reporting emissions will help supply chain providers such as UPS, DHL, Amazon, etc. to modify the mode of transport for the last and first mile delivery by implementing the use of electric cargo bicycles, drones or delivery by foot, hence reducing urban emissions. DHL has proved the concept by replacing conventional vans with using 27,000 bicycles of electric and cargo type in their Germany division, which saved up to 8 tCO2e per year (DHL, 2019). Also, Amazon has expanded to cargo bikes connected to trailers that can carry up to 45 packages as well as introduced electric three-wheelers and compressed natural gas vehicles in their delivery operations in Europe and India as well as the use of Prime air drones which will make deliveries faster, more automated and efficient and reduce the requirement of van delivery subsequently reducing traffic and pollution (Amazon, 2019). Emissions reduction Reducing emissions through technology innovations and achieving a high standard of equipment performance can substantially reduce emissions of supply chain logistic operations. An initial and effective step of supply providers to reduce emissions is through training and educating employees of the impacts the company’s logistics carbon footprint has on a global scale as well as teach methods for reducing fuel consumption. Drivers can reduce fuel consumption through acceleration and shifting techniques, and by limiting average speeds, idling time, accessory usage, and the number of stops made (Sathaye, 2006). DHL goes a step further and implementing companywide guidance where they define targets and measures their sub-contractors, which employees have to follow to achieve their environmental targets (DHL, 2019). Furthermore, DHL is aiming at certifying 80% of their employees as GoGreen specialists, where training is provided for all employees to achieve fundamental environmental awareness (DHL, 2019). Furthermore, technology options on logistics freight such as roof deflectors, wide-base tires, etc. as seen in Table 2 that reduce the drive train friction, aerodynamic drag, rolling resistance, operation of vehicle accessories, and inertial forces for acceleration can be of logical use as they reduce emissions and cost. Examples of Amazon using skirts (panels attached to the lower side edges of a truck to make it aerodynamic) and automatic tire inflation systems to maximize fuel efficiency as well as mud flaps which are designed to allow water and airflow through them have been seen to minimize drag and save 454L of diesel fuel per vehicle annually (Amazon, 2019). On the other hand, DHL has implemented photovoltaic mats fitted on trailers which can save up to 4.5tCO2e per vehicle annually and reduce fuel consumption by up to 5% (DHL, 2019). EV technology being extremely advanced in the past years, with primary targeted short distance deliveries, with Tesla currently developing an electric truck with a promised range of 300 miles will heavily influence the logistics market (Tesla, 2021). Amazon, having ordered 100,000 electric vehicles has also implemented a ‘’shipment zero-order’’ where zero-emissions 100% battery-electric or hydrogen-fuelled vehicles deliver the products. They also heavily invest in EV charging station infrastructure for their partners to use, hence accelerating the global use of EV’s in the logistics industry (Amazon, 2019). On the other side, DHL is focusing on upgrading fleets of cargo aircraft to new more fuel-efficient aircraft, which saw a reduction of emissions of 18% (DHL, 2019). Additionally, studies conducted by Ang-Olson and Ostria (2005), as indicated in Table 3, found that alternative fuels such as emulsified diesel, biodiesel, propane, and more, have lower emissions of toxic GHG such as PM and NOx. Post-combustion solutions such as NOx catalyst can also reduce the toxic gases exiting the exhaust of vehicle hence could be perceived as another viable solution. Recommended Circular Economy in the Construction Industry In addition to changes made to fuel type, innovations are done in combustion processes such as cooled exhaust gas recirculation, combustion optimization, improved fuel injection, variable geometry turbocharges, and onboard diagnostics that can reduce emissions. Not directly associated to supply chain providers, however, if these features and alternatives are enquired, automotive manufactures will follow the trend and comply (Sathaye, 2006). Furthermore, supply chain providers also own warehouses where the products are stored hence a further carbon footprint is present in their businesses. To minimize their environmental impact warehouses of companies such as Amazon, DHL and Prologis use solar panels, with Amazon having up to 80% of the energy used is renewable in a facility center (Amazon, 2019) (Prologis, 2019) (DHL, 2019). Furthermore, Amazon as a business invested heavily into the wind and solar projects, in this way offsetting their operational carbon. Changing operations Technologies based on reducing vehicle miles traveled can be both of economic and environmental benefit to companies. As found by Sathaye (2006) and displayed in Table 4, which includes vehicle routing tracking, real-time traffic updates, and facilitation of business-to-business communication and collaboration. Tesco supermarket delivery service estimated to reduce emissions by 23,000tCO2e over five years by applying techniques of logistics systems analysis and optimization (Sathaye, 2006). Moreover, DHL through increased recording of data via sensors, intelligent network, and route planning, and the use of alternative modes of transport achieved to optimize processes and connect logistics chains across continents. Also, by the implementation of artificial intelligence (AI), big data, predictive analytics, and algorithms, potential incidents in the supply chain are identified and managed in real-time, further improving efficiency and reducing delays which ultimately account for emissions (DHL, 2019). Amazon, due to the evidently large number of products shipped daily had to use data and algorithms to consolidate as many shipments as possible onto one vehicle or plane. This ensured the efficient transportation and use of space on freights hence maximizing the capacity and reducing unused space to be wasted (Amazon, 2019). Reverse logistics And finally, a more radical measure for environmental protection that may have economic and societal consequences extends further from the logistics of supply chains. A broader framework of life-cycle assessment (LCA) associated with reverse logistics and circular economy principles could be used by companies to improve their environmental burden. Reverse logistics, which focus on waste management and return flow of products back along the chain could be an important study for the supply chain and its partners to minimize their waste (McKinnon, et al., 2015). As Amazon's free packaging program suggests, the packaging of products has been certified to be shipped with their original packaging without the need of the amazon extra protective box. This policy and design initiative will increase the volume of goods transported and massively reduce the waste of cardboard boxes. Also, by encouraging the use of 100% recyclable packages, Amazon has eliminated 33% of packaging material (Amazon, 2019). REFERENCES References U.S. Federal Highway Administration, 2005. The Freight Technology Story: Intelligent Freight Technologies and Their Benefits. Office of Freight Management and Operations. Amazon, 2019. Goals and Strategies & Climate pledge, s.l.: https://sustainability.aboutamazon.com/?energyType=true&workerCount=true&engagementProgram=true&productCategory=true. Ang-Olson, Jeffrey & Ostria, S., 2005. Assessing the Effects of Freight Movement on Air Quality at the National and Regional Level: Final Report. Ang-Olson, Schroeer, J. & Schroeer, W., 2002. 'Energy Efficiency Strategies for Freight Trucking: Potential Impacts of Fuel Use and Greenhouse Gas Emissions, s.l.: Transportation Research Record 1815. DHL, 2019. DHL Sustainability Report, s.l.: s.n. Tesla, 2021. Semi. [Online] Available at: https://www.tesla.com/semi London, M. o., 2019. CENTRAL LONDON ULTRA LOW EMISSION ZONE – SIX MONTH REPORT, London: Greater London Authority. Sathaye, N. L. Y. H. A., 2006. The Environmental Impacts of Logistics Systems and Options for Mitigation. UC Berkeley Recent Work. SFC, 2020. Leading the way to efficient and zero emission freight and logistics, s.l.: Smart Freight Centre Annual Report . Prologis, 2019. 2019 Prologis ESG Impact Report. McKinnon, A., Browne, M., Whiteing, A. & Piecyk, M., 2015. Green Logistics : Improving the Environmental Sustainability of Logistics. s.l.:Kogan Page. Marshall, D., J., Teoh, S.-K. & Nazaroff, W., 2005. Intake fraction of nonreactive vehicle emissions in U.S. urban areas, s.l.: Atmospheric Environment 39 (7).

Stress and Strain are fundamentals of the Civil Engineering discipline and are not to be confused Solid Mechanics look into various material's motion and deformation under the action of forces. STRESS Stress is the ratio of applied force F to a cross-section area - defined as "force per unit area". The idea of stress could be used to describe the state of affairs at any point inside a solid in a much more general way. Also, stress could be used to predict when the material will break. "Stress tells us how hard- that is, with how much force - the atoms at any point in a solid are being pulled apart" Essential Books for Civil Engineering Students Amazon's Choice Different types/names of stress exist such as normal tensile stress which acts perpendicular to the surface and shear stress which acts in a parallel to the surface. Stress units are usually MN/m2 ( MEGANEWTONS PER SQUARE METRE) in SI units and p.s.i ( POUNDS PER SQUARE INCH) which is mostly used in America. STRAIN Strain which is not to be confused with stress is a completely different thing. Strain tells us how far the atoms at any point in a solid are being pulled apart. Strain is a ratio of the extended length divided by the original length therefore, does have units and hence it is expressed as a percentage. Strain in association with stress is used to analyse and better understand material properties such as stiffness, strength and much more concepts are based on these two basic and principle concepts. Read more: Concrete variable radius arch dam explained The 5 Greatest Engineers of All Times What's the most impressive ancient structure in the world?

How to Determine the Financial Strength of Contractors Contracting organisation financial strength is important to be determined within the tendering and selection stage to ensure the appointment of the appropriate contractor with limiting the risk of bankruptcy and project incompletion. The financial information of tenderers could be assessed through the collection of financial reports from the PQQ as indicated in PAS91. Short term and long-term financial stability of the companies could be found by assessing their solvency and calculating the current ratio and acid test ratio as indicated in Equation 1 and Equation 2 respectively. A current ratio of 1 suggests a financially stable company but a trend over the last few years should be looked into to see the fluctuation of the ratio (Council, North Hertfordshire District, n.d.). Moreover, an acid test ratio may provide a measurement of liquidity and the readily convertible into cash assets of the company with a ratio of 1.0 suggest a financially healthy contractor. Furthermore, assessment of how efficiently the company’s management is utilising the resources at their disposal to generate revenue and drive profits up, as well as the comparison of significant debt is an important criterion for assessment. The managerial aspect of a business could be assessed through the ROCE ratio and revenue/total assets as shown in Equation 3 and Equation 4 where higher ratio values indicate an effective contract winning strategy suggested to be important ratios by (Singh & Tiong, 2005) and (Council, North Hertfordshire District, n.d.). Furthermore, a multiple criteria decision-making (MCDM) technique as used by (Singh & Tiong, 2005) could be implemented to get an overall grade on the financial performance of tenderers with a focus given on ratios deemed more important to the client. Nevertheless, it should be pointed out that a downturn in the construction industry or of the global economy could put a financially strong company into financial difficulties such as the currently unseen COVID-19 pandemic. Financial Protection As recently seen when economy recovers from recession the pressure on contractors increases as material, labour and financial resources become stretched (Wakeford, 2015). Thereafter, risk is increased on the client where the project is required to be delivered on time and within budget limits. The major client risk is the insolvency of the contractor during construction period which could be financially limited by applying measures within the contracts signed as secondary options such as performance bonds and parent company guarantees (NEC4, 2017). Parent/Holding Company Guarantees A parent company guarantees are used to give the contractor recourse to a more substantial corporate entity that will underwrite the employer’s payment obligations under the contract which provides essential financial and legal assurance for the client if the subsidiary contractor is to go into insolvency (Meakin R, 2006). Credit checks and financial evaluation of the parent company can be examined through the PQQ (PAS 91:2013, 2017), which could reveal the suitability of the capital and assets of the holding parent company to act as guarantee as well as legality of the guarantee contract. The parent company is obliged to either complete the works in accordance with the contractors’ original obligations on behalf of its subsidiary company or fund the completion of the contract by others (K. Hughes , 2019), hence an advantage of guaranteed completion is present. Secondary option X4 could be used from the NEC4 contract options as where a holding company guarantee is required with the contractor obligated to agree on the guarantee scope of works (NEC4, 2017) (Rowlinson, 2018). Performance bonds Furthermore, a performance bond could be used in the contractual agreement as a form of financial security generally offered by a third party such as banks or insurance companies which give the client a binding enforceable payment guarantee up to a fixed amount of money in the situation of poor performance or project incompletion by the contractor. Performance bond doesn’t guarantee project completion but a maximum sum payable for the damages by the contractor to the client for the breach of contract. Bond insurance rates vary depending on the creditworthiness of the contractor, with premiums often range between 2% and 3% of the amount guaranteed which is normally 10% of the contract price. Contractors would normally pass on this premium to the client as part of their tender price submissions for the project. NEC4 secondary option X13 can be used as a condition precedent to the execution of the contract. Specified circumstances defined by the client that will be used to recall the sum of money from the bond should be clearly stated in the scope when contractors agree to the contract terms (Rowlinson, 2018) (NEC4, 2017). You may also find useful : Procurement systems advantages, disadvantages and risks for the construction client: The procurement options mentioned provide satisfactory performance in the objectives of the golden triangle with both advantages and disadvantages to the construction client based on the project size and client priorities. Procurement strategies to deliver better value for clients: The continuing search for maximum value for money in construction work has, in recent years, increasingly focused attention upon the procurement process. Effective delivery of a project requires that the supply chain clearly understands the client’s needs and specific business case to deliver an economical and efficient end product. Cost, Time and Quality | The Golden Triangle in Construction: Recent research into major projects by (Dalton, 2008) as shown in Table 1 found that 75-80% of the causes of projects failing were due to procurement, the definition of project requirements, and the client’s management capabilities. Esurance of timely cash flow payments to contracting organisations Negative cash flow means a company is doomed to fail. To ensure timely payment of both the main tier 1 contractor and supply chain sub-contractors under the NEC4-2017 contracts, option Y(UK) 1 could be used by setting up a project bank account (PBA). Through this bank account all the payments of the work done on the project will be made (Rowlinson, 2018). A PBA ensures visibility and transparency of supply chain cash flow payments made by the main contractor and it has enabled the condensation of the payment cycle as Highways England managed to achieve a condensed payment period of average 18/19 days from the usual 30 to 60 days. The client and project manager should ensure the trust deed forms for the PBA are included in the contract and are outlined in tender documentation and when the project is commissioned the contractor is responsible for opening and running the bank account. Also, due to that cash flow performance depends on the project managers cash flow management, additional training or competent managers would be effective on improving the overall performance of cashflow payments (Investopedia, 2020). Useful References Council, North Hertfordshire District, n.d. CRITERIA USED FOR FINANCIAL EVALUATION OF CANDIDATES IN THE PROCUREMENT PROCESS. [Online] Available at: https://www.north-herts.gov.uk/ Singh, D. & Tiong, R. L. K., 2005. Evaluating the financial health of construction contractors D. Singh and R. L. K. Tiong Economic slowdown and fierce competition in the construction industry in recent years has led many construction companies to pull out of projects due to deep financial. [Online] Available at: https://www-icevirtuallibrary-com. Wakeford, M., 2015. Construction Client Protection – Managing financial risks outside the contract. [Online] Available at: https://www.linkedin.com/pulse/construction-client-protection-managing-financial-risks-mark-wakeford/ Meakin R, C. W. C. L., 2006. Clyde & Co Firm Foundations: bonds and guarantee, s.l.: Firm Foundations Seminar. PAS 91:2013, 2017. Construction prequalification questionnaires, s.l.: BSI. K. Hughes , 2019. Understanding the NEC4 ECC Contract – a practical handbook, s.l.: Routledge. Rowlinson, M., 2018. A Practical Guide to the NEC4 Engineering and Construction Contract, s.l.: John Wiley & Sons, Incorporated.

The construction industry which embraces the sectors of buildings and civil engineering had a 1.9 trillion euros turnover in Europe from 2011 to 2018 and a value of new work of 118,977 million pounds in the UK in 2019 which makes the industry an important contributor to the function of economies globally. Inevitably, the industry attracts a wide variety of clients all of whom will have their own objectives and priorities for their particular different projects of dramatically different types, sizes, and complexity (Cooke & Williams, 2010) (Morledge & Smith, 2013). When a client decides to pursue a project a number of important strategic decisions need to be made before the commissioning of the project works to ensure an efficient and successful final product. In accordance with the code of practice of CIOB, procurement should be considered to be the process of identification, selection, and commissioning of the contributions required for the construction phase of the project (CIOB, 2014). Therefore, procurement systems play an important role in project success as they establish the roles, relationships, responsibilities, and risks carried by the parties that form the overall organization and communication structure for the management, administration, and control of a project. Used books: Appropriate selection of the procurement system is an important strategic decision that with the guidance of the project manager and a good understanding of the procurement criteria the client must take in the early stages. Provided in the Construction Round Table (1995) in their publication “Thinking about Building” as well as Cooke & Williams, 2010 and Morledge & Smith, 2013 suggest the criteria that must be considered when selecting the appropriate procurement system as listed in (Morledge & Smith, 2013)Table 1. Complex technically advanced design and highly serviced construction requirements of certain projects play a major importance in selecting the most suitable procurement system with the division of responsibility are solely based on client decisions on the management style of consultants and contractors. Furthermore, different procurement options provide different levels of risk and control allocation to and by the client with time, cost and quality, being the main categories of consideration as well as providing the range of competition given in projects and the ability to make changes. You may also find useful : Procurement systems advantages, disadvantages and risks for the construction client: The procurement options mentioned provide satisfactory performance in the objectives of the golden triangle with both advantages and disadvantages to the construction client based on the project size and client priorities. Procurement strategies to deliver better value for clients: The continuing search for maximum value for money in construction work has, in recent years, increasingly focused attention upon the procurement process. Effective delivery of a project requires that the supply chain clearly understands the client’s needs and specific business case to deliver an economical and efficient end product. Cost, Time and Quality | The Golden Triangle in Construction: Recent research into major projects by (Dalton, 2008) as shown in Table 1 found that 75-80% of the causes of projects failing were due to procurement, the definition of project requirements, and the client’s management capabilities.