This research investigated the longitudinal shear transfer mechanism in composite shallow cellular floor beams. The shear transfer mechanism is different with the headed shear studs used in composite construction. The shear resisting properties and behaviour of the shear transfer mechanism has not been studied previously. Experimental and analytical studies were carried out with the aims of improving and optimizing the design details, and advancing the method of shear connection in shallow floor beam construction. The composite shallow cellular floor beam investigated in this research is a new type of beam fabricated by welding two highly asymmetric cellular tees along the web. The shear connections of this type of composite beam are formed by the web openings, which transfer longitudinal shear force. Four types of these shear connections were studied: concrete-infill-only, tie-bar, ducting and web-welded-stud shear connections. In total, 24 push-out tests were performed in two test series to investigate the load-slip behaviour and shear resistance of the shear connections under direct shear force. The failure mechanisms of the two forms of shear connections were extensively studied, which lead to the development of a design method for the composite action. The concrete infill element passing through the web opening is subject to a complex three-dimensional stress state, and it is difficult to analyse it using the mathematical model rather than empirical formula. Finite Element Analysis of the concrete-infill-only shear connection was performed with a parametric study to further verify the design method that has been developed. Two flexural tests were carried out on a full-scale composite shallow cellular floor beam with a solid slab. The shear connections investigated in the flexural tests were: concrete-infill-only and tie-bar shear connections passed through the web. The behaviour and performance of the shear connections in the flexural tests were compared with those in the push-out tests. The degree of shear connection of the two flexural tests was determined in the back analysis using plastic theory with measured material properties. Based on the findings of the push-out tests and flexural tests, two design methods of deflection check and moment resistance were developed for composite shallow cellular floor beams at the serviceability limit state and the ultimate limit state respectively. The deflection check design method is based on the uncracked section properties of the composite beam. The moment resistance design method developed in this thesis is compatible with the design methods of BS5950 and Eurocode 4 (EC4).

The worldwide housing shortage has stimulated a search for appropriate, easy, fast and cost-effective new ways of wall construction. Among many technologies found to have promise is mortarless technology using dry-stack interlocking bricks/blocks. This thesis is about such mortarless walling technology and in particular: how to improve wall-construction flexibility, the effects of brick irregularities on wall alignment accuracy and wall behaviour (stiffness, strength) when subject to lateral forces. The flexibility of mortarless technology (MT) has been enhanced by the development of new bricks (centre-half bat and tee brick): the introduction of closer bricks led to the formation of two new bonds (patterns) namely Shokse and Lijuja bonds. It is now possible to construct more than half-brick-thick walls, to attach more than half-brickwide piers (buttresses) onto walls, and, using special bricks, to construct polygonal and curved walls using interlocking bricks. Three methods (theoretical modeling, physical experiments and computer simulation) were used to analyze the effects of brick imperfections on wall alignment accuracy. Theoretical analysis confirmed that brick moulders should concentrate on achieving parallel top and bottom faces rather than achieving true square-ness. Physical column assembly compared three brick-laying strategies namely: “random”, “reversing” and “replace”. The columns assembled using the “reversing” and “replace” strategies realized alignment improvement factors of 1.6 and 2.9 respectively over “random” strategy. The research also revealed that grooving, to prevent bricks making contact near their centre lines, improved column alignment by factor 2.13 and stiffness by factor 2.0, thus allowing construction of longer and higher walls without strengthening measures. In order to attain alignment accuracy in accordance with BS 5628-3:2005 in a dry-stack mortarless wall, this research recommends using full bricks with top and bottom surface irregularities not exceeding ±0.5mm for un-grooved bricks, and up-to ±0.9mm for grooved bricks. Further analysis was undertaken with respect to resource-use implications (cement, water, soil) of employing MT. Using MT will save 50% of wall construction cost and 50% cement consumption, which ultimately will reduce 40% of carbon emissions.

The prevailing paradigm in indoor environment control of office buildings often excludes natural ventilation, due to the fact that its dynamic nature may not be compatible with the close control of mechanical conditioning systems. The challenges will be greater in terms of the potential high magnitudes of wind and buoyancy forces at high levels of tall buildings. This research is concerned with the prospect of tall office buildings that are purely naturally ventilated. It is proposed that “segmentation” might offer the least risky approach for natural ventilation design of non-domestic tall buildings. Accordingly, the generic design procedure are proposed for investigating the influence of segmentation on ventilation air flows: firstly, the single-cell envelope flow model is adopted to evaluate the steady-state bulk flows through openings under a specified design condition; secondly, dynamic thermal modelling with an air flow network module is used, because of the particular importance of the coupling between the airflow and thermal process for evaluating the year-round ventilated cooling potential of targeted spaces. The chosen thermal model utilizes a multi-cell airflow network model (AFN) since the targeted buildings can no longer be described by a single-cell model; thirdly, computational fluid dynamics (CFD) simulation is suggested in the later design stage to cope with insufficient resolution of local airflow distribution in previous modelling stages; finally, the overall performance of comfort ventilation is then interpreted in relation to adaptive thermal comfort theory by the use of Building Bioclimatic Charts, which offers a way of rapidly testing whether or not natural ventilation is likely to produce comfortable conditions. The novelty of this work lies not in the methodology, which uses available modelling tools, but in the evaluation of naturally ventilated tall buildings with reference to segmentation in the climatic context of Taiwan. The effect of segmentation is evaluated by comparing the overall ventilation performance under three different building configurations, namely the isolated, segmented and non-segmented tall buildings. The overall objectives are to determine whether the magnitudes of air flow rates and the resultant flow velocity can achieve the desired comfort ventilation over a range of specified conditions. Potential scenarios where the design goals may not be ensured are identified. The feasibility for naturally ventilated tall office buildings in hot and humid climates is clarified accordingly.

Fire is a continuous threat to life and property. The total annual UK fire loss is estimated to be 0.25% of its gross domestic product (GDP) (Goddard, 1995). According to fire statistics, more than 12 million fires break out every year in the United States, Europe, Russia, and China killing about 166,000 people and injuring several hundreds of thousands (Morgan and Wilkie, 2007). Polymers which take up 80% of the organic chemical industry, are known for their high flammability with the production of heat, corrosive toxic gases, and smoke (Bent, 2010). Improving the fire retardancy of polymeric materials is a major concern and also a major challenge. Nanotechnology could have a significant impact on polymeric materials through the achievement of polymer nanocomposites (PNs) with enhanced functional properties (Giannelis, 1996, Schartel and Batholmai, 2006). If this can be achieved, there will be an enormous increase in the use of improved flame retardant (FR) PNs in mass transportation, aerospace, and military applications where fire safety will be of utmost importance (Horrocks and Price, 2008). In this research project nanoparticles that could have a synergistic effect with traditional FR systems, or that could have a FR action (nano-fire extinguishers), were formulated and surface modified during continuous hydrothermal synthesis (CHS). The bespoke nanoparticles were developed in a structure that could be easily integrated and effectively dispersed into a polymeric matrix. A solvent blending approach for integrating and dispersing colloidal organic modified nanoparticles into polymeric matrices was developed. The impact of nanoparticles of different morphologies including nanospheres, nanoplates, and nanorods on epoxy mechanical, thermal, and flammability properties was evaluated. A laboratory based technique using a Bunsen, video footage, and image analysis was developed to quantify the nanocomposite's direct flame resistance in a repeatable fashion. A new self extinguishing epoxy nanocomposite was developed which showed an enhanced performance in extreme conditions and with good mechanical properties.

Fires in mine tunnels and other underground space are a serious hazard, that can, if left unchecked, result in significant economic loss and human tragedy. In the UK, methods such as water deluge, foam application, and various types of handheld extinguishers have been used, but statistics show no improvement in the incidence of fire. Water mist has the potential to be an effective fire suppression system for tunnel spaces. Typical water mist systems utilise small droplets of around 100 micron that have a low terminal velocity and a high surface to volume ratio. This leads to behaviour distinct from that of traditional sprinklers. Various mechanisms of action have been identified: removal of heat; oxygen depletion; fuel cooling; attenuation of radiation; and disruption of air flow. The relative importance of each is case dependent. Current research has focussed almost exclusively on enclosures with minimal or no ventilation, and no data relevant to the application of mist in tunnels exists. In this thesis, a series of Computational Fluid Dynamics (CFD) simulations, based on published experimental data, are used to indirectly validate a CFD model of a hypothetical water mist system applied to a real tunnel fire, and to improve the understanding of how water mist performs in a strongly ventilated space. The water mist is represented by a Lagrangian-based particle-tracking model. This model is fully coupled to the continuous phase, accounting for transfer of momentum, heat, and mass. A 16m3 unventilated enclosure is used first to validate a pool fire model based on 0.3m square pools of methanol (27 kW) and hexane (115 kW). The behaviour of a thermal plume in a tunnel with forced ventilation is then validated, initially using a fixed volumetric heat source of 7.5kW in a small-scale tunnel, and then on a full-scale 3m square cross-section tunnel with a 3m diesel pool using the pool fire model. The water mist model is validated with the enclosure fire, and a sensitivity study assesses the effect of droplet diameter, spray velocity and angle, and water flow rate on the performance of the system. Finally water mist is applied to the tunnel fire At low ventilation, oxygen depletion and air-flow disruption are significant, whereas at high ventilation the only effect of the mist is to remove heat and reduce temperature.

In recent years, the rapid development of new information technologies has significantly impacted on the product development process as strategic means to gain competitive advantage in a global market. In the engineering domain, powerful computer-based tools such as Computer Aided Design systems enable engineers to perform various design tasks and realise product concepts in the early phase of the product development process. However, the increasing complexity of modern products as well as the globalization of product development further necessitate distributed and collaborative design environments. This is where different computer systems and dispersed specialists in similar or different disciplines need to collaboratively be involved in shared design activities. Therefore, the integration and communication of engineering information are two of the most key technical factors in ensuring successful collaboration. The current application of information technology in supporting collaboration during the design process is limited to either a document-based or a common format-based exchange level. These methods provide relatively simple forms of collaboration compared with desired distributed and collaborative design environments that can deliver more effective ways of collaboration. The work detailed in this research investigates the advantages of using modern distributed information technologies alongside a suitable framework and a product model to support multi-disciplinary collaborative design. The work also involves exploring other important issues related to real-time collaborative design environments. These are design transaction management, access control, communication, and version management. The research work employs modern technology and distributed computing to enhance the processes of collaborative building design. The research proposes a framework and a product model to extend the functionalities of stand-alone and single-user design systems to facilitate synchronous collaborative design where distributed designers can work concurrently on a centralised shared model and carry out all necessary communication and data exchanges electronically. The implemented framework proposes a data transaction management approach that ensures efficient concurrent access to the model data and maintains data consistency. The framework also employs software agents to automatically access and operate on the information exchanged among the collaborators. The proposed product model in this work extends an adopted model to support access right control and version management. The work is implemented in an experimental software as a client-server model. .Net technology is used for implementing the framework and the product model and virtual reality technology is used to allow for intuitive interaction with the system. The research concludes that the utilisation of the modern distributed technologies can effectively induce change in the design process toward a more collaborative and concurrent design. As demonstrated within this work, these technologies with a suitable system design can meet the main requirements of a real-time collaborative building design system.

Geothermal heat pumps (GSHPs), or direct expansion (OX) ground source heat pumps, are a highly efficient renewable energy technology, which uses the earth, groundwater or surface water as a heat source when operating in heating mode or as a heat sink when operating in a cooling mode. It is receiving increasing interest because of its potential to reduce primary energy consumption and thus reduce emissions of GHGs. The main concept of this technology is that it utilises the lower temperature of the ground (approximately <32°C), which remains relatively stable throughout the year, to provide space heating, cooling and domestic hot water inside the building area. The main goal of this study is to stimulate the uptake of the GSHPs. Recent attempts to stimulate alternative energy sources for heating and cooling of buildings has emphasised the utilisation of the ambient energy from ground source and other renewable energy sources. The purpose of this study, however, is to examine the means of reduction of energy consumption in buildings, identify GSHPs as an environmental friendly technology able to provide efficient utilisation of energy in the buildings sector, promote using GSHPs applications as an optimum means of heating and cooling, and to present typical applications and recent advances of GSHPs. The study highlighted the potential energy saving that could be achieved through the use of ground energy sources. It also focuses on the optimisation and improvement of the operation conditions of the heat cycle and performance of the GSHP. It is concluded that GSHP, combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors, is extendable to more comprehensive applications.

The main purpose of this programme of research was to establish characteristic water levels to which new and existing properties of masonry construction can be protected against flooding. Typical flood protection systems often rely on the structural strength of the building and in doing so generate significant lateral loadings. Current guidance appears to be based on the results of a single experimental study and no calculation technique is currently available to determine suitable characteristic levels. The research aim was addressed by conducting a series of experimental tests at model scale and by developing a theoretical analysis. Model scale masonry wall panels were successfully tested in a geotechnical centrifuge and were subject to hydraulic loading or uniform wind loading. Wind loading was considered to allow validation of the experimental procedure to results in the literature. Wall panels were constructed from both brick and block units and the effect of different mortar strengths, openings, vertical loadings and cavity construction were assessed. The experimental procedure showed very good repeatability in terms of ultimate load and generally a yield line type failure mode was observed. A theoretical analysis based on yield line analysis was developed using spreadsheet software and verified using the results from the experimental programme. The analysis gave a good approximation of the experimental ultimate loads, but the optimised failure mode was not always consistent with that observed in the tests. A parametric study was completed to assess the effect of varying parameters not considered in the experimental study and in addition a typical domestic property was modelled to assess its resistance against flood loading. The characteristic water level for the weakest wall of the property was found to exceed the value given in the guidance, of 0.6 m, by 38 % and signified the importance of completing the correct modelling procedure.

Realising the benefits of implementing Building Information Modelling (BIM) tools and processes on projects worldwide, the architecture, engineering and construction (AEC) industry is rapidly moving towards BIM adoption. This calls for higher levels of interoperability amongst existing design and analysis tools used by various project team members. An approach to achieving higher levels of BIM maturity and interoperability is to adopt open, non-proprietary data exchange standards such as the Industry Foundation Classes (IFC). Efforts are currently underway to establish IFC-compliance in analysis tools. Establishing interoperability between architectural BIM models and energy analysis tools has been a challenging effort. With the industry chasing renewable energy targets for existing and new building stock, it becomes imperative to incorporate analysis tools for renewable energy systems (RES) in this effort. A plethora of tools are used by the project team to assess the performance of various RES in existing buildings or in post-design stages of new buildings. A holistic RES simulation tool is required that can assess various RES and their impact on the building’s energy consumption, carbon emissions and operational costs. Developing this tool’s interoperability with architectural BIM models would lead to higher adoption. The aim of this thesis is to develop a methodology to support renewable energy simulation by using architectural BIM models based on open data exchange standards thereby enhancing their interoperability. The research process involved a literature review of the existing RES analysis methods and approaches of developing IFC-compliant analysis tools. A methodology was developed that involved a standardised conceptual framework that can be used to establish compliance in RES analysis tools with open-data exchange schemas. The conceptual framework was implemented in a solar PV simulation model by means of a prototype. The prototype was validated against existing PV analysis tools and presented to industry experts to gain their feedback. It was concluded that the tool supported RES assessment of buildings in early design stages and could be widely adopted as a BIM tool by the AEC industry.

This thesis concerns the highly complex relationship between cost and design decision-making. A theoretical cost function is described by examining the output requirements of the design activity, and the constraints placed on the input to the process by current cost generation procedure. The description takes the form of a set of preferred characteristics or alternatively, criteria on which the potential of a future costing process might best be judged. A particular interpretation of this set of characteristics is described, which produces the tentative specification for a new generation of cost models. An implementation of the specification resulted in the computer-based cost simulation model ACE (Analysis of Construction Economics). This interactive, knowledge-based cost model is used to investigate a series of cost relationships and cost thresholds, both to exemplify its possible applications, and to produce some means of determining the validity of both the general approach, and the particular interpretation which ACE represents.