Direct electric curing is the method by which the hydration reactions within concrete are thermally accelerated by passing an alternating electric current through the sample. This use of electricity as a means of supplying heat to young concrete and mortar has become recognised as a more effective and energy efficient form of accelerating the curing process than traditional steam curing. The present investigation involves studying the affects of thermally accelerated curing of cementitious materials in comparison to normally non-heated curing. Prior to mixing, tests are performed on the constituents of the cementitious mixes. Results of these tests are used in the creation of mix designs for mortar and concrete samples. A range of concrete mixes are designed with and without additives and admixtures are used to make cubes, slabs and beams. From the testing results, the factors affecting the short and long term properties of electrically cured cementitious materials are investigated and heating regimes are presented to achieve specific properties of both strength and durability at specific ages. A substantial section of reinforced concrete is required to gain representative results in electrically curing reinforced concrete slabs. Compressive strength is difficult to measure due to the electrical distortion affects of inserts and the damage caused by coring so that at present, basic maturity concepts are used as a compressive strength guide which limits the validity of results obtained. This research looks at refining these concepts to include early age heating effects induced by direct electric curing. The microstructural development of concrete when subjected to accelerated curing is also considered. The affect of delay periods and maximum temperature is studied using a scanning electron microscope and the results presented.

The engineering design process is an iterative and distributed process. It is often characterized by multi-disciplinary teams in multiple places working together, on a single project, using different models and software tools. The current collaboration approaches in AEC industry often focus on integrating and managing multiple models from multi-designers. Building Information Modelling (BIM) is playing a major role in facilitating collaboration. BIM provides an opportunity to electronically model and manage the vast amount of information embedded in a building project, from conception to completion. In the design process, changes in the models are inevitable and very common. They can occur at any stage of the project, from different sources, and for various reasons, which can have significant effects on the process. Versioning is a solution for design change management. Many model versions can be created and distributed among the disciplinary teams. Despite many researches done on the subject and the availability of some software applications that deal with changes in design, the mechanism to cope with the changes among different model versions needs further studies to increase the management efficiencies and ensure designers have an up-to-date version of the model. The challenges of information exchange in project management result from: a combination of the enormous amounts of information generated, the large variety of design systems involved, and data format utilised by different disciplines at various design stages. The Industry Foundation Classes (IFC) standard represents a paradigm shift for data and information exchange. The main goal for developing the IFC model is to provide a neutral data format to exchange information among different software programs. IFC models reflect the current state of BIM model. They do not take into consideration the process and results of latest changes among different BIM users nor record the history of earlier changes. This research work therefore investigates how to improve the process of managing the design changes from different disciplinary models. This research developed a collaborative methodology to manage the design changes in different models. It tackles the challenges of the versioning process as a change management approach. This is done through extending the capability of the existing IFC schema to control and manage different design changes in different BIM models. The proposed extended IFC incorporates the changed information of the latest model version and provides the complete history of changes of all earlier model versions. A prototype system was developed in this research to implement and validate the extended IFC and to demonstrate using it to improve the management of the whole design process. The research process involved undertaking a literature review to identify knowledge gaps and challenges in the areas of the (design process, BIM, IFC, and change management). The research also investigated and analysed the IFC standard and identified two key requirements of extending the IFC and implementing the prototype. Further aspects of this research include developing a framework to facilitate a collaborative design, extending the existing IFC schema, designing and implementing the prototype based on the extension, and validating and evaluating the extended IFC and the prototype system. The research concludes that the extended IFC to handle versioning can effectively improve collaborative design. It addressed concepts involving comparing, storing, classifying, extending managing, versioning, exchanging, and sharing of modelling information in a collaborative way. The proposed process of managing design changes covered an important gap associated with current IFC models, which can be incorporated in future releases of the IFC standard.

Mitigation of progressive collapse after an initial failure has become a primary concern of engineers in recent years. Often alternative load paths are sought to redistribute load from the damaged area. It has been recognised for some time that the omission of compressive membrane action (CMA), also termed ‘arching action’, can lead to a significant underestimation of load capacity. An investigation has been conducted to ascertain whether the additional load carrying capacity from CMA can provide an inherent alternative load path to aid robustness. A series of scaled specimens with industry standard detailing have been designed for an experimental investigation. Reinforced concrete elements were modelled in the double span scenario once an intermediate column has been removed. The test rig used allows the central support to be removed followed by the application of a point load applied at midspan; the system is determinate including measurement of the horizontal reaction. Subsequent to the flexural response two modes of membrane action are induced, initially compressive until tensile membrane extends load capacity at high values of deflection. The response during the latter tensile phase is outside the scope of this research. Comparisons of experimental data with analytical methods inclusive of CMA have demonstrated that whilst conservative the method by Merola (2009) provides a reasonable prediction. This method has been utilised in a study of a series of flat slab structures with a range of column spacings. The inherent restraint stiffness provided by the surrounding slab and frame has been quantified using FEA and has allowed for the extent to which CMA can improve the robustness of a structure to be determined.

Pile heat exchangers are expected to make a significant contribution to meeting UK and EU renewable energy and carbon dioxide reduction targets. However, design for the thermal capacity of pile heat exchangers has to date been largely based on methods developed for borehole heat exchangers. Piles have a much smaller aspect (length to diameter) ratio than boreholes and consequently their thermal behaviour is different in a number of important ways. This thesis explores these differences and makes recommendations for improved assessment of pile heat exchanger thermal capacity. Traditionally vertical heat exchanger design assumes separation of the thermal effects in the ground and in the pile. A transient temperature response function is used to assess temperature changes in the ground and a steady state resistance is applied to the pile concrete. In this thesis existing approaches to temperature response functions are critically assessed for use with thermal piles. It is important to take into account the larger pile diameter, which causes increased temperature changes in the short term. In the long term, the shorter pile length will result in reduced temperature changes as steady state is reached more quickly. Simple 2D numerical modelling has been carried out and the results used to derive a new method for determining pile thermal resistance. However, for large diameter piles, the time taken for the pile to reach steady state suggests that the use of a constant thermal resistance in design is not always appropriate. In these cases it is recommended that a transient temperature response function is used to assess the response of the ground and the concrete together. The applicability of short duration thermal response testing for pile heat exchangers has been examined. Modelling and case study data has shown that the technique is only reliable for piles of 300mm diameter or less. For the special case of large diameter piles with centrally placed heat transfer pipes then it is possible to use the test to determine the thermal conductivity of the pile concrete, but not pile thermal resistance.

Modern office buildings are often open plan buildings with a frame consisting of flat RC slabs, RC columns and non-load bearing internal and external partitions and facades. These modern framed structures are more flexible than older conventional buildings with load bearing walls and are less susceptible to differential settlement damage. The use of conventional guidelines for differential settlement on modern flexible framed structures may therefore be over-conservative. The literature review of the study highlights the factors producing differential settlement, the types of damage caused by differential settlement and conventional guidelines for limiting differential settlement damage. Conventional guidelines focusing on 2D structures lack provision for the 3D deformation of a structure. To determine the behaviour of a modern flexible framed structure a numerical experiment was performed, which consisted of the design according to British Standards and Eurocodes of a 3D, 5-bay by 5-bay, 6 storey flat slab RC frame with pad foundations on clay. The behaviour of the designed structure undergoing differential settlement was then analysed by means of linear-elastic finite element analyses. The results show firstly that it is possible to normalise structural behaviour to the soilstructure stiffness ratio, secondly the importance of 3D deformation of the structure and thirdly that stiffer load-displacement responses of foundations may also affect the behaviour of the structure. A stiffer load-displacement response may occur with the reuse of foundations

The primary aim of the project was to develop the basis for a set of rules to be used in the design of RHS slim floor edge beams with web openings. However, since the research is fundamental in nature, the findings are also applicable to other situations where it may be advantageous to cut holes in load bearing tubular members of rectangular cross-section. The study considered the influence of the number and size of holes upon resistance and stiffness in bending, shear, and torsion and combined analytical Finite Element modelling with large and small scale pseudo-static (short-time static loading) laboratory testing. In all but one category of tests (see below), good agreement was achieved between experimentally measured quantities (such as capacities, deflections and strains) and the corresponding Finite Element predictions, allowing parametric investigations to be conducted with calibrated analytical models. Preliminary design recommendations are presented based on the results of the parametric study and laboratory tests. The design advice was developed with regard to existing recommendations for the design of perforated I-beams, and was produced in a form that allows integration with modern limit state design codes. Aspects of behaviour requiring further investigation have been identified and categorised. Torsion tests on full scale RHS without web openings yielded some unexpected results. Elastic and plastic capacities measured in the laboratory were significantly lower (12–20%) than those predicted by the Finite Element models and the thick walled torsion theory used as the basis of the British and European design procedures. Attempts were made to determine the cause of this behaviour and a number of possibilities were eliminated. Although the anomalous results have not been fully explained, evidence of similar behaviour in previous full-scale testing was discovered.

Good building design can provide a myriad of benefits. There is ample evidence suggesting an association between design attributes and various outcomes for users and other stakeholders of built environments. Despite is importance, design quality is found to be overlooked in building projects in favour of other objectives such as time and cost. Recent initiatives have attempted to highlight the value of design quality, however, their focus have been mainly on post project completion and building evaluation. ‘How’ design quality - with its complex nature –is achieved during the projects has seen little empirical attempt. The research in this thesis, therefore, aimed to improve the understanding of design quality achievement in building projects by exploring the critical success factors (CSFs) and stakeholder attributes. A multi-phase, mixed methods approach was developed to fulfil this aim. In the first phase, the theory and methods offered in ‘project success’ and ‘stakeholder management’ assisted in devising a developmental process to a) identify, validate and evaluate the CSFs, and to b) explore stakeholder attributes using three major analysis models. A preliminary interview study, then, explored the viewpoints of 11 architects on the topic and verified the research aim and directions. A matrix-based model was also used to map the bi-directionality between design quality and its stakeholders. The second phase, consisting of a qualitative study followed by a quantitative one, first identified 36 potential CSFs from the perspective of 10 experts and then validated 28 of them through a questionnaire survey of 129 individuals with architecture and client backgrounds. ‘Brief’, ‘communications’ and ‘leadership’ were revealed as the most important CSFs. Using principal Component Analysis to assess the interrelationships between the CSFs in 126 building projects extracted 7 components that could meaningfully represent the CSFs. Moreover, Regression Analysis was employed to establish the causal relationship between these components and the design quality success criteria of functionality, build quality and impact. It was found that the components collectively contribute to the achievement of design quality in real projects but differently to each of its success criteria. Also, by applying the second stakeholder model, it was found that clients and architects had the highest level of power, proximity and urgency with regard to design quality decisions while users and facility managers were low in these attributes. In phase 3, Social Network Analysis was used to model and visualise the stakeholder relationships with regard to design quality in a case project (third stakeholder model). 21 members of the stakeholder groups were approached and their involvement, influence and communication effectiveness were assessed. Apart from the evolving understanding obtained through the above process, the research contributed by developing conceptual frameworks for a) design quality CSFs, b) design quality related stakeholder relationships, and c) success criteria of building projects. Moreover, for the first time, the dynamism of stakeholder communications in a construction project was visualised for different stages. Based on the knowledge emerged, the research also proposed a holistic evaluation of design quality achievement to enhance the current DQI tool.

The primary objective of this research study was to observe the changes in the physical properties of cement coated secondary aggregates, namely surface roughness and angle of internal friction and how these properties are related to the performance of Open Graded Friction Course asphalt mixtures, OGFC made from these materials under laboratory Uniaxial, deformation and rutting testing simulating the traffic loading and temperature of the materials in service. The secondary aggregates, namely Croxden natural gravel aggregates, which is rejected by road engineers for use in road surfacing was upgraded with a specifically designed cement coating. Asphalt mixtures mechanical properties in terms of stiffness modulus, deformations and rutting were determined and analyzed using state-of-the-art laboratory test equipment and supported by technical literature from different information and resources. Three aggregate types were considered in this study; Arcow rock crushed aggregates( as a control aggregate), Croxden aggregate (as a secondary or low quality aggregates) and cement coated Croxden aggregate (as an upgraded material). One aggregate gradation was designed for all mixture types and the adopted aggregate gradation had a nominal maximum aggregate size (NMAS) of 14mm. Two binder types were selected, 100/150 pen binder and 40/60 pen binder to represent the soft and hard binders respectively that are commonly used by road engineers. This research also documents a survey of literature review that led to the design of a novel machine that is eagerly needed by the pavement industry to boost the knowledge and understanding of real tyre-road interaction. Computer software, SOLIDWORKS, was used to create a 3-dimentional model of the machine that was jointly named by the Highway Agency and Tarmac ltd., as Low Cost Asphalt Tasting Equipment (LoCATE). The machine was designed for use and for the first time to investigate the performance of the said mixtures under real traffic loading and environmental conditions and to correlate its results with those obtained using Repeated Load Indirect Tensile Test (RLIT) and Repeated Load Axial Test (RLAT), which were carried out at 10°C, 20°C, 30°C and 45°C. At an advanced stage of this research work and when the cost of fabricating LoCATE was found impossible to be met by LJMU, wheel tracking tests were done on the materials studied as a replacement of LoCATE and this part of the research program was achieved at Wolverhampton's bituminous testing laboratories in collaboration with Tarmac Ltd. In general, the results of this research investigation indicate that the introduction of cement coated aggregates to OGFC led to an outstanding improvement in the chemical properties of the coated natural aggregates and the stiffness and deformation properties/resistance of the road mixtures containing them. This was in comparison with that made from the uncoated aggregates in all the tests that have been carried out within this research study. Also, the effects of elevated temperature were investigated and it was found to have significant influence on the engineering properties, Indirect Tensile Stiffness Moduli (ITSM) and permanent deformation/rutting characteristic of the mixtures were also investigated. Outstanding new results were achieved, using LJMU cement coating paste for coating the waste natural aggregate and as thus this will hopefully eliminate the restriction imposed by road engineers on the use of natural gravel aggregates in road pavement surfacing layers. This is an outstanding knowledge extension in this field and marks a starting point for more research in this ever growing industry i. e. the use of waste and recycled aggregates in construction industry.

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This research constructs and tests a model of the organisation of building projects for maximum benefit to clients. The model is developed from systems theory, independently of conventional organisational assumptions. It is based upon the premise that the process to be managed must be identified before organisational structures can be designed and it recognises the influence of environmental forces upon projects. The model proposes that the process of building provision consists of sub-systems created by decision points and identifies the interdependency and hence the differentiation within and between the subsystems. The major propositions of the model are that; a) there should be a match of differentiation and integrative effort, b) the operating and managing systems should be differentiated, c) the managing system itself should be undifferentiated and, d) the client and process of building provision should be integrated. The model was tested against three commercial buildings for private clients. Data is presented from interviews and other sources and is interpreted using Linear Responsibility Analysis, which was adapted and developed in this research. The testing method examines the overall compatibility of the model and the test projects, and also identifies the causes of deficiencies in the outcomes of the projects and whether they can be explained by divergence of the projects from the model. The model was found to be valid for the type of project used in the tests. It provides a theoretical framework against which the effectiveness of organisation structures for the management of building projects can be predicted and which can be used for the design of such structures. It is suggested that Linear Responsibility Analysis provides a useful tool for organisation analysis and design. Finally, implications of the results for the organisation of building projects in practice are discussed.