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Composite slabs are gaining wide acceptance in many countries as they lend themselves to faster, lighter and more economic in construction buildings. The strength of composite slabs system relies on the bonding action between the concrete and the steel deck, the shear connections and the cross-sectional resistance of steel beam. However, structural behaviour of composite slab is a complex phenomenon and therefore experimental study is often conducted to establish the actual strength of the structure under ultimate load capacity. The main objective of this study is to determine the structural behaviour of composite slab system until ultimate limit state. Total of two specimens are examined in order to obtain failure mechanism of the composite structure under full load capacity. A new design approach of composite slab for roofing system are proposed in this study to construct a composite slab system that can float in the water but not wash away by flood. The lightweight materials in this composite construction are cold-formed steel and foam concrete. The system focuses on the concept of Industrialised building system (IBS) to reduce the cost and construction time.

I argue that the official story about the collapses of the Twin Towers and building 7 of the World Trade Center, according to which the collapses were caused by fire – combined, in the case of the Twin Towers, with the effects of the airplane impacts – cannot be true, for two major reasons. One reason is that fire has never, except allegedly three times on 9/11, caused the total collapse of steel-frame high-rise buildings. All (other) such collapses have been produced by the use of explosives in the procedure known as “controlled demolition.” The other major problem is that the collapses of all three buildings had at least 11 features that would be expected if, and only if, explosives had been used.

I also show the importance of the recently released of 9/11 Oral Histories recorded by the New York Fire Department. With regard to the Twin Towers, many of the firefighters and medical workers said they observed multiple explosions and other phenomena indicative of controlled demolition. With regard to building 7, many testimonies point to widespread foreknowledge that the building was going to collapse, and some of the testimonies contradict the official story that this anticipation of the building's collapse was based on objective indications. These testimonies further strengthen the already virtually conclusive case that all three buildings were brought down by explosives.

I conclude by calling on the New York Times, which got the 9/11 Oral Histories released, now to complete the task of revealing the truth about 9/11.

When implemented effectively and systematically across a curriculum, high impact practices (HIP) have the potential to increase student engagement and result in higher student achievement. The United States Air Force Academy (USAFA) is a four-year military university with a large liberal education core curriculum that provides the foundation for service and officership in the United States Air or Space Forces. Building on the liberal education core, the civil engineering (CE) major’s courses begin with the cornerstone field engineering course, paired with a two-week co-curricular experience for students at an Air or Space Force installation. With its motto “construct first, design later,” the field engineering course is an HIP and quintessential experiential learning course that gives students a practical frame-of-reference for future analysis and design courses. The CE major culminates with another HIP, the capstone design course, which gives students the opportunity to demonstrate their skills, building confidence in their ability to successfully apply those skills to the increasingly complex problems they will face after graduation. This book chapter provides a case study of the CE major at the USAFA, documenting the HIPs across the majors’ program, and highlighting the key elements and benefits of each.

The expected operational lifespan of modern buildings has become disturbingly short as buildings are replaced for reasons of changing cultural expectations, style, serviceability, locational obsolescence and economic viability. The same buildings, however, are not always physically or structurally obsolete; the materials and components within them are very often still serviceable. While there is some recycling of selected construction materials, such as steel and concrete, this is almost always in the form of down cycling or reprocessing. One significant impediment to reuse is that buildings are not designed in a way that facilitates easy recovery of materials and components. This chapter explores the potential for the recovery of materials and components if buildings were designed for such future recovery, utilizing the strategy of design for disassembly. As well as assessing material waste, this chapter presents research into the analysis of the embodied energy in buildings, highlighting its significance in comparison with operational energy. Analysis at material, component and whole-of-building levels shows the potential benefits of strategically designing buildings for future disassembly to recover this embodied energy. Careful consideration at the early design stage can result in the deconstruction of significant portions of buildings and the recovery of their potential through higher order reuse and upcycling.

A mathematical model for sustainable optimization is presented. The sustainability parameters are linked to end-of-life considerations in product design and development. The sustainability considerations such as total embodied energy, eco-materials selection, CO₂ emission, cost savings due to recycling and reuse including the water savings are presented for helical compression springs used in mattresses.

The consideration of alternative sources of material for construction is imperative to reduce the environmental impacts as two-fifths of the carbon footprint of materials is attributed to the construction industry. One alternative material with improved biodegradable attributes which can contribute to carbon offset is bamboo. The commercialisation of bamboo in modern infrastructures has significant potential to address few of the Sustainable Development Goals (SDGs) itemised by the United Nations, namely SDG 9 about industry, innovation and infrastructure. Other SDGs covering sustainable cities and communities, responsible consumption and production and climate action are also indirectly addressed when utilising sustainable construction materials. Being a natural material however, the full commercialisation of materials such as bamboo is constrained by a lack of durability. Besides fracture mechanisms arising from load-induced cracks and thermal modification, the durability of bamboo material is greatly impaired by biotic and abiotic factors, which equally affect its natural rate of degradation, hence fracture behaviour. In first instance, this chapter outlines the various factors leading to the durability limitations in bamboo material due to load-induced cracks and natural degradation based on recent findings in this field from the author's own work and from past literature. Secondly, part of this chapter is devoted to a new approach of processing the surge of information about the varied aspects of bamboo durability by considering the powerful technique of artificial intelligence (AI), specifically the artificial neural network (ANN) for prediction modelling. Further use of AI-enabled technologies could have an impactful outcome on the life cycle assessment of bamboo-based structures to address the growing challenges outlined by the United Nations.

The railway track system is the platform by which loads from moving trains are transferred to the underlying soil or supporting infrastructure such as bridges. The most common type of railway track system is ballasted track, which has been in use for over a century. Ballasted track has proved versatile. It can be constructed using locally available materials and with modifications to the rails and sleepers, crossings transferring trains from one route to another can be created. The structure of a ballasted track system consists of two main parts. The upper portion, termed the superstructure, comprises the rails, fastenings and sleepers. It is formed of components whose shape, stiffness and strength are designed and closely controlled. Below the superstructure is the substructure, which comprises the ballast and sub-ballast. Although the materials used in the substructure may have been specified, their engineering properties and geometric placement are less well controlled. In this chapter, we will explore how a typical ballasted track system transfers load to the ground and the ways in which the track form deteriorates, requiring maintenance and eventually renewal.