The thesis mainly deals with predicting the lateral failure pressure of masonry panels which carry little or no axial loading. This type of isotropic and orthotropic panels can be found as cladding for framed construction or upper floors of multi-storey load bearing structures. The failure criterion has been established recently for an orthotropic brittle masonry panels, but no such criterion exists for isotropic panels. In the first phase of the work, three mortar cross beams, each of 5 different aspect ratios have been tested to establish the failure criterion in biaxial bending for isotropic material. The specimens made of isotropic material cracked and failed simultaneously without shedding of load in the stronger direction whereas in case of orthotropic material, cracking was followed by 'load shedding' to the stronger direction and a subsequent failure of the specimens. The failure criterion that was developed for the isotropic material was incorporated in a finite element plate bending program to predict the failure pressure of panels subjected to lateral loading. In order to test the theoretical model, few isotropic panels with different boundary conditions were tested. This include tests carried out on a total of 4 panels that are simply supported on three sides and four sides under idealised boundary conditions with no rotational restraints. In case of three sides supported panels, there was no difference whether it is free at the top or at one of the vertical sides as the properties were same in both directions and hence only one type of panel was tested. A good agreement between the theoretical and experimental results was observed. The second phase of the project was to develop a quick and reliable method of design by predicting the failure pressure of laterally loaded masonry panels. Artificial neural networks, as a computational tool, offers very exciting technique for computing non-linear engineering problems, similar to the current situation that exists for the design of laterally loaded masonry panels. A hybrid system that combines the capabilities of artificial neural networks and case based reasoning is developed in this thesis. In the present study, multilayered feedforward net with back propagation algorithm is used. To develop this application, a neural network program was developed in C++ incorporating back propagation algorithm and sigmoid activation function. An excellent user interface for this program was developed using Microsoft Foundation Class (MFC) libraries.

This thesis investigates the dynamics and control of a Rubber Tyred Gantry (RTG) crane which are commonly used in container handling operations. Both theoretical and experimental work has been undertaken to ensure the balance of this research. The concept of a Global Sensing System (GSS) is outlined, this being a closed loop automatic sensing system capable of guiding the lifting gear (spreader) to the location of the target container by using feedback signals from the crane's degrees of freedom. To acquire the crucial data for the coordinates and orientation of the swinging spreader a novel visual sensing system (VSS) is proposed. In addition algorithms used in the VSS for seeking the central coordinates of the clustered pixels from the digitised images are also developed. In order to investigate the feasibility of different control strategies in practise, a scaled-down, 1/8, experimental crane rig has been constructed with a new level of functionality in that the spreader in this rig is equipped with multiple cables to emulate the characteristics of a full-size RTG crane. A Crane Application Programming Interface (CAPI) has been proposed to reduce the complexity and difficulty in integrating the control software and hardware. It provides a relatively user-friendly environment in which the end-user can focus on implementing the more fundamental issues of control strategies, rather spending significant amounts of time in low-level device-dependent programming. A control strategy using Feedback Linearization Control (FLC) is investigated. This can handle significant non-linearity in the dynamics of the RTG crane. Simulation results are provided, and so by means of the CAPI this controller is available for direct control of the experimental crane rig. The final part of the thesis is an integration of the analyses of the different subjects, and shows the feasibility of the real-time implementation.

Brickwork panels are often required to resist out-of-plane lateral loading due to wind. In many cases these panels contain window openings. Although extensive research has been done on the lateral strength of walls without openings and the bending moments coefficients have been given in the British Standard Code of practice for the use of masonry, little is known about the behaviour of brickwork panels with window openings subjected to wind loading. The work described in this thesis, therefore is mainly confined to the lateral strength of unreinforced brickwork wall panels with window openings subjected to uniformly distributed loading simulating the wind pressure. The experimental work was carried out on half-scale single-leaf rectangular panels having window openings. The investigation relies on extensive experimental work to gather data on the behaviour of unreinforced brickwork at cracking and at failure. Tests done on 160 wallettes, 24 cross-beams and 16 walls are presented in Chapters 3, 4 and 5. The material properties were defined from the prisms and wallettes tests. The cross-beams were tested to obtain the behaviour of masonry in bi-axial bending. A moment interaction diagram at cracking in bi-axial bending has been presented which is subsequently used to predict the experimental cracking pressures of the cross-beams and panels. An apparent increase in the flexural tensile strength perpendicular to the bed-joints was found in bi-axial bending compared to the ultimate flexural tensile strength in uni-axial bending. The proposed cracking criterion, when combined with the finite element analysis or orthotropic plates, predicts cracking pressure reasonably well for the walls having window opening. The strip method and yield-line analysis, both, were used to predict the ultimate failure of the panels. Extensive theoretical yield-line solutions for the panels of various boundary conditions containing window openings subjected to wind loading have been presented in Chapter 5.

The thesis comprises of 44 published papers mainly dealing with various aspects of structural masonry. The success of masonry and its use in high-rise buildings and other civil engineering works required better understanding of materials and its structural behaviour. The thesis describes the most comprehensive and systematic research investigation undertaken in the area of material science relevant to structure, structural performance and design methodology for plain, reinforced and prestressed masonry. Novel test methods for obtaining tensile strength of individual brick and bi-axial strength of masonry in flexure are described. Several series of full-scale tests to investigate the behaviours of brickwork subjected to combined compression and shear, multi-storey brick shear wall structure subjected to wind loading, progressive collapse, lateral strength of wall panels with and without precompression, interaction between wall and floor slabs are also described. Based on the tests of real structures, design methods for multi-storey masonry structures subjected to vertical and wind loading, and to limit the progressive collapse due to accidental loading are recommended. A Coulomb type of equation is suggested to calculate the ultimate shear strength of masonry. A theory to predict the lateral strength of masonry subjected to precompression has also been described. Methods developed to predict the shear and flexural strengths of reinforced and prestressed masonry are elucidated. A plastic method, similar to concrete, is used for the theoretical prediction of the shear strength of prestressed beams. An analytical technique for calculating the load-deflection and the ultimate moment capacity of reinforced and prestressed sections is also presented. The technique takes into account all the sources of non-linearity; such as non-linear material behaviour, cracking and tension stiffening.

This thesis investigates the structural behaviour of reinforced brickwork pocket-type sections using the twin approach of experimental and theoretical studies. The behaviour, in shear, of this type of reinforced brickwork is studied experimentally through tests conducted on 8 full-scale beams, under four-point loading, longitudinally-reinforced, and in which a range of shear-span/effective depth ratios (<I>a/d</I> = 2.0-6.0) and % reinforcement (ρ = 0.61%-1.60%) were investigated. Aspects of structural behaviour studied include (a) the ductility of the sections via their moment-curvature relationships as well as their load-deflection behaviour, (b) the shear behaviour of the sections vis-a-vis cracking development and growth through the various stages of loading up to and including the ultimate point. Since the reality of shear failure is such that the members were acting under both shear and flexural stresses, flexural behaviour of the sections was also investigated for the pocket-reinforced beams. The theoretical formulations were based on small scale representative prism test results conducted on the brickwork and the results obtained were compared with experimental findings. A summary of existing methods for predicting shear strength is presented. The method proposed is based on an adaptation of the technique based on plastic analysis which was used originally for predicting the shear strength of concrete beam sections. The ultimate shear strength results obtained experimentally for the eight pocket-reinforced beams are compared with theoretical predictions based on the proposed method. This adapted method is based on a rigorous analysis of all known brickwork beams which were reported to fail in shear. The flanged-action behaviour of these wall sections was investigated in order to ascertain its existence and characteristics. To this end, six full-scale simply-supported, reinforced brickwork pocket-type slab specimens, in which the % steel was kept constant and the pockets spacing varied, were tested to determine the characteristics of flanged-action behaviour in the walls. A method is proposed for the calculation of the effective width associated with the different cases of pocket stem spacings. This method is based on an analysis of experimental strain measurements across the pocket stems.

Smoke control systems limit the spread of smoke in buildings, in the event of a fire. They have only been provided as engineered systems for the past forty years. There is little published data available on their performance in real fire situations. The effectiveness of a smoke control system is dependent on the accuracy of the modelling of the fire and smoke environment, and on the performance of the installed system. This thesis examines how these two aspects of smoke control systems may vary. An experimental program was developed to examine smoke movement from a compartment and within an atrium. Comparison of the results was made to a set of design calculations. Velocity measurements were made using particle imaging velocimetry (PIV). This unobtrusive technique has provided additional information on smoke flow movement by providing a visual image of the flow, which is capable of measurement to generate velocity fields. The cause of faults during the life-cycle of smoke control systems and the effect on their performance have also been examined. A questionnaire was developed to determine engineers' experiences with smoke control systems. In addition to completing the questionnaire, some respondents also provided information for case studies. From this, and information from published sources, a taxonomy of smoke control system failure has been developed. This may form the basis for the future study of the reliability of smoke control systems.

The calcium sulphoaluminate hydrates are important components of Portland cement and constitute the principal matrix formers of some sulphoaluminate cements. Their practical importance lies in the involvement as intermediates and products of the hydration of portland cements under geothermal conditions. Ettringite is a complex mineral (Ca₆[Al(OH)₆]₂(SO₄)₃.26H₂O) formed during the initial stages of Portland cement hydration at ambient temperature, by reaction of sulphate ions released by gypsum (CaSO₄.2H₂O) with tricalcium aluminate (Ca₃Al₂O₆). After exhaustion of gypsum, the remaining tricalcium aluminate in solution reacts with already formed ettringite transforming to monosulphate (Ca₄Al₂(SO₄)(OH)₁₂.xH₂O). At higher temperature (>100°C), ettringite is unstable and transforms to monosulphate. Monosulphates are known to exist is at least four different hydrate forms (x = 8,10,12,14). In this study the stability of calcium sulphoaluminate hydrates were mapped in various environments (variable relative humidity, temperature and alkalinity). The monosulphate hydrates were obtained by hydrothermal synthesis using microwave radiation at 120°C. Their formation is via ettringite thermal decomposition in autoclave conditions under autogenous pressure. It has been shown that a series of calcium sulphoaluminate hydrates can be obtained depending on temperature and water activity. The interconversion of the calcium sulphoaluminate hydrates was found to be an easy and rapid process, whereby metastable phase are readily formed, indicating the lability of Ca-OH-Al-SO₄ system. The kinetics and the mechanism of growth of calcium sulphoaluminate hydrates are known to influence the development of mechanical properties and the characteristics of cements. The ettringite crystal growth process was evaluated from the point of view of its influence on crystal morphology. General crystallisation methods for ettringite synthesis were developed starting from supersaturated solutions of pure phases and its morphology was found to vary with crystallisation factors (temperature for instance); ettringite crystals are generally hexagonal rods with different aspect ratios.

Buildings last typically 50 to 100 years, and with climate change predicting hotter summers and warmer winters, buildings designed now and many existing buildings will need to cope with the future climate. The aim should be for buildings to provide comfortable environments for occupants without using excessive heating or cooling energy, which will exacerbate carbon emissions. This is particularly important for office buildings, as the productivity of occupants can be affected if conditions of the workplace are not ideal. Different models and scenarios for predicting future weather for the UK were studied in this thesis. These provide either monthly or daily data of weather variables for the next 100 years including daily maximum, minimum and average temperature, solar irradiation, wind speed and humidity levels. The data from two state-of-the-art models from the Hadley Centre in the UK, HadCM3 and HadRM3, were compared with real observed data to test their reliability, both with average values, as well as near-extreme values, which are useful for building design. It was found that for HadCM3, the temperature data has a severe cold-bias, but solar radiation matched well with real data. For HadRM3, the reverse is true. Its temperature data are fine, but there is an over-prediction of days with high solar radiation, even in days with high cloud cover as shown by an analysis of extra-terrestrial based clearness index values. For both models, the wind data is extremely high compared to real data. Test Reference Years (TRYs) and Design Summer Years (DSYs) were selected for 2020s, 2050s and 2080s using data from these climate models to estimate future energy usage for heating and cooling; and the feasibility of using natural ventilation as the sole means of providing summer cooling in future periods respectively. It was found that the existing methods for selecting TRYs and DSYs could be improved for future weather data. Since buildings respond to hourly changes to outside conditions, a number of algorithms were analysed and appropriate ones were developed to generate hourly weather data for dry bulb temperature (DBT), global irradiation (GSR) and diffuse solar irradiation (DSR) from daily data available from the climate models. These perform better than existing algorithms as they make use of all the daily parameters available. TRYs and DSYs with generated hourly values were run on a 2nd order room model that was developed during this research. This provides extra flexibility over existing building simulation programmes. It was found that the fall in heating demand is approximately equalled to the rise in cooling demand as a result of climate change up to 2080s in all four sites, and that natural ventilation alone would not be able to provide summer cooling in the UK in the near future. Office buildings complying with the Building Regulations of 2002 in the south of England would require air-conditioning by 2020s, those in the north of England by 2050s and those in Scotland by 2080s. However, the majority of existing office buildings in the UK have lower standards of specification. This thesis shows that cooling and emissions will be a major problem in the future climate. Making these buildings work in the future could prove to be an even greater challenge than to design energy efficient new buildings.

The creation of an effective construction schedule is fundamental to the successful completion of a construction project. Effectively communicating the temporal and spatial details of this schedule are vital, however current planning approaches often lead to multiple or misinterpretations of the schedule throughout the planning team. Four Dimensional Computer Aided Design (4D CAD) has emerged over the last twenty years as an effective tool during construction project planning. In recent years Building Information Modelling (BIM) has emerged as a valuable approach to construction informatics throughout the whole lifecycle of a building. Additionally, emerging trends in location-aware and wearable computing provide a future potential for untethered, contextual visualisation and data delivery away from the office. The purpose of this study was to develop a novel computer-based approach, to facilitate on-site 4D construction planning through interaction with a 3D construction model and corresponding building information data in outdoor Augmented Reality (AR). Based on a wide ranging literature review, a conceptual framework was put forward to represent software development requirements to support the sequencing of construction tasks in AR. Based on this framework, an approach was developed that represented the main processes required to plan a construction sequence using an onsite model based 4D methodology. Using this proposed approach, a prototype software tool was developed, 4DAR. The implemented tool facilitated the mapping of elements within an interactive 3D model with corresponding BIM data objects to provide an interface for two way communication with the underlying Industry Foundation Class (IFC) data model. Positioning data from RTK-GPS and an electronic compass enabled the geo-located 3D model to be registered in world coordinates and visualised using a head mounted display fitted with a ii forward facing video camera. The scheduling of construction tasks was achieved using a novel interactive technique that negated the need for a previous construction schedule to be input into the system. The resulting 4D simulation can be viewed at any time during the scheduling process, facilitating an iterative approach to project planning to be adopted. Furthermore, employing the IFC file as a central read/write repository for schedule data reduces the amount of disparate documentation and centralises the storage of schedule information, while improving communication and facilitating collaborative working practices within a project planning team. Post graduate students and construction professionals evaluated the implemented prototype tool to test its usefulness for construction planning requirements. It emerged from the evaluation sessions that the implemented tool had achieved the essential requirements highlighted in the conceptual framework and proposed approach. Furthermore, the evaluators expressed that the implemented software and proposed novel approach to construction planning had potential to assist with the planning process for both experienced and inexperienced construction planners. The following contributions to knowledge have been made by this study in the areas of 4D CAD, construction applications of augmented reality and Building Information Modelling;  4D Construction Planning in Outdoor Augmented Reality (AR)  The development of a novel 4D planning approach through decomposition  The deployment of Industry Foundation Classes (IFC) in AR  Leveraging IFC files for centralised data management within real time planning and visualisation environment.

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