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The British Construction Industry has been criticised for many years. Comparisons have shown that construction in the United States, Canada, France, Germany and Australia is cheaper and quicker than present practice in the UK. In the UK the traditional system of construction, separates the two main disciplines of design and construction. The design is carried out by a consultant and the construction is carried out by a contractor. As a result of this the construction industry is suffering from many problems such as design complexity, increasing costs and longer construction duration. This thesis addresses the detail design stage of the design process. Detail design decisions have a significant impact on cost and time. The UK contractors have no important influence at the design stage, because designers do not take adequate and accurate account of construction methods, actual costs and the value of time. The traditional system prevents this involvement. To overcome this problem, constructability was cited as being c, apable of improving project performance. There is, however no clear understanding of why or how to formally incorporate construction knowledge as part of the process of design. The designer could reduce problems for the contractor by being more aware of the construction process and the potential delays and inefficiencies which are often introduced during design. Similarly, the contractor could aid the design by contributing his knowledge of site practices to the designer and improving communications during the construction process. The thesis focuses on integrating construction expertise with the design process at the detail design phase. It explores both the designer's and the constructor's view points, and presents a design process model.

This thesis is concerned with the phenomenon of Rising Damp, which is a complex example of the simultaneous flows of volume (water), heat, solutes and electricity within a porous material. The physical complexity of this natural occurrence has required that the phenomenon be reduced into a series of scientific areas or related topics, which are presented as separate chapters. A full account of the structure of the thesis can be found in the introduction section. The common areas covered in this work are mathematical description of the loss of moisture by damp porous materials (i.e. evaporation) and of the movement of moisture within unsaturated porous materials both in terms of non linear "Diffusivity" type expressions (Chapter Three) or more usefully in terms of non linear "free energy" type expressions (Chapter Eight); capillary suction developed in damp walls. Other less common topics investigated are leaching of soluble materials from the porous matrix and prediction of the consequent increase in matrix permeability to fluid; electro kinetic aspects of Rising Damp; coupling of transport processes within porous materials. Several of the topics discussed in this work are common to several scientific disciplines giving rise to a 'looseness' and 'multiplicity' of nomenclature. To overcome this problem, particular care and space has been devoted to explaining the terminology used in this work, which is especially useful to readers who are unfamiliar with this area of study.To conclude, the thesis covers the essential aspects of Rising Damp and, as such, it may be used as a platform from which the phenomenon can be investigated more comprehensively

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The aim of this thesis is to answer the two research questions: how can design for manufacture be applied during building component design and building design?; and how can the application of design for manufacture be successful in improving the productivity and quality of building component production and building construction? These two questions emerged during exploratory research focused on the use of design to improve construction industry productivity and quality. Subsequent review of manufacturing literature revealed that the two key principles of design for manufacture are standard production design improvement rules and standard production design evaluation metrics. Review of construction literature, and a survey involving over one hundred and fifty industry practitioners, revealed that, whilst rules and metrics for building components and buildings do not currently exist, there are no fundamental reasons why they could not be developed and applied successfully. These findings led to the generation of the research hypothesis: design for manufacture principles can be applied successfully to building components and buildings. The research hypothesis was tested by two interventions, action research within a private business which manufactures and installs building components, and a case study with a multi-national company which designs and constructs buildings. These interventions resulted in significant business benefits. Further, they confirmed that it is both technically feasible and economically viable to apply rules and metrics to building component design and building design, and that doing so can improve the productivity and quality of building component production and building construction. Following analysis of research findings, strategic plans were developed for the successful application of rules and metrics. These were validated through interviews with senior construction industry practitioners. Contributions to knowledge include the strategic plans for successful application of rules and metrics. These cover the full range of organisations working in the construction industry and, together with the detailed descriptions of the interventions, offer practical guidance for industry practitioners seeking to improve productivity and quality. The research also makes a contribution in the area of research methodology. It has shown that threats to research validity in the construction industry can be counteracted by applying a quasi-experimental perspective to action research interventions and case studies.

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This document provides a framework for the assessment of gas explosion impact on structures. It shows how the probability of a structure achieving a predefined level of success in withstanding a defined gas explosion scenario may be calculated. The thesis opens with a general introduction to the need for assessing the impact of gas explosions in offshore installations. In the second chapter relevant literature regarding the existing theory and approaches used in assessment of gas explosions is reviewed. In particular, limitations of existing techniques are highlighted. The experimental data that is available to the author is also discussed. In the third chapter a set of objectives is defined. Meeting these objectives would allow many of the outstanding issues in gas explosion assessment, highlighted in chapter two, to be addressed. These objectives essentially define the need for assessment of explosions to relate to the impact upon the structure they engulf and that the impact is dependent not only upon the explosion but upon the structure so effected. The fourth chapter extends an existing technique of applying time-averaging windows to pressure-time histories from explosions. In this chapter, the importance of an approach to analysing explosions that relates directly to structural response is first established. An improved understanding of the effect of explosion parameters upon explosion magnitude is also made. The fifth chapter makes use of conventional signal analysis techniques to address weaknesses of time-averaging approach. These techniques allow a better relationship between identified structural response frequency and quantification of loading to be reached. These techniques also allow analysis of the explosion time history to be made in the frequency domain. Our understanding of the explosion parameters on explosion magnitude is again advanced. Whereas the fifth chapter allows analysis to be made in the frequency pressure domain, the sixth chapter shows how analysis can be made in the frequency-loading domain. This is achieved by assessing the impact of pressure-time histories on a simple oscillating structure, a single degree of freedom object. Of all the techniques developed, this is believed to be the most appropriate. In the seventh chapter we begin to apply the techniques developed by assessing, among other things, the inherent repeatability of an explosion and our ability to accurately predict the magnitude of the explosion. We start to generate a body of statistical data relating to accidental gas explosions. Chapter eight shows how the knowledge gained in previous chapters might be applied within a framework that is relevant to current practices in risk assessment. The framework selected is known as the limit state approach. It is shown how performance criteria for the structure undergoing gas explosions might be set and how the probability of the structure meeting these conditions might be assessed.

Previous studies on acoustic requirements for performers of classical music proved that early reflections were of critical importance for good ensemble conditions. However, strong early reflections may produce an unpleasant tone quality. Diffusers are sometimes used to reduce the negative effects caused by large specularly reflecting surfaces. The aim of the research project is to better understand what happens when diffusers are applied to the enclosure walls of a stage in a concert hall. Two aspects are examined: the changes produced to the sound field measured on the orchestra platform, and the manner in which musicians perceive diffuse early reflections in comparison with specular early reflections. Results of objective measurements show that the most noticeable property of diffusers on the early sound field is the smoothing of the impulse response. Diffusers attenuate strong early reflections. Besides, diffusers give a better sound energy distribution by providing reflections outside the specular sector: the standard deviation of several acoustic parameters is somewhat smaller with diffusers. It was found that diffusers do not eliminate comb filter effects and that they do not have a great influence on EEL, ST and clarity. The subjective aspect resulting in the greatest consensus among the subjects is the following. The overall tone quality is improved by diffusers. The overall sound quality is influenced by the amplitude of early reflections and by the reception angle of the reflections. Diffusers may also affect articulation, clarity, self and mutual hearing, but to a minor extent. Musicians' requirements regarding the fine structure of early reflections differ according to the size of the ensemble who is performing, the room volume, the power and directivity of the instruments played, and the type of music (or desired tone quality).