No description available.

No description available.

Buildings expend vast quantities of energy, which has a detrimental impact on the environment. Buildings systems are often oversized to cope with possible extreme environmental conditions. Building simulation provides an opportunity to improve building thermal design, but the available tools are typically used in combination in order to overcome their individual deficiencies. Two such tools, often used in tandem are computational fluid dynamics (CFD) and dynamic thermal modelling (DTM). DTM provides a coarse analysis, by considering external and internal thermal conditions over a building (including its fabric) over time. CFD is usually used to provide steady state analysis. Boundary conditions typically in the form of surface temperatures are manually input from DTM into CFD. CFD can model buildings dynamically, but is not commonly used, since solving for hugely different time constants of solid and air pose significant limitations, due to data generated and time consumed. A technique is developed in this study to tackle these limitations. There are two main strands to the research. DTM techniques had to be incorporated into CFD, starting from first principles of modelling heat transfer through solid materials. These were developed into employing the use of functions such as the 'freeze flow' function (FEF) and the 'boundary freeze' function (BFF) in combination with a time-varying grid schedule to model solids and air simultaneously. The FFF pauses the solution of all governing equations of fluid flow, except temperature. The BFF can be applied to solid boundaries to lock their temperatures whilst all other equations are solved. After extensive research the established DTM-CFD Procedure eventually used the FEF and BFF with transient periods and steady state updates, respectively. The second strand of research involved the application of the DTM-CFD Procedure to a typical office space over a period of 24-hours. Through inter-model comparisons with a fully transient simulation, the DTM-CFD Procedure proved to be capable of providing dynamic thermal simulations 16.4% more efficiently than a typical CFD code and more accurately than a typical DTM code. Additional research is recommended for the further improvement of the DTM-CFD Procedure.

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The construction, commissioning and hand-over of pharmaceutical manufacturing buildings have become increasingly controlled by the requirements of regulatory agencies. Legislation requires that the process of validation is undertaken to establish that the facility is constructed in-line with the principles of pharmaceutical Good Manufacturing Practice (GMP). The validation process acts to ensure that the construction and building services systems are designed, installed and operate as intended and do not affect the quality of the manufactured product. A central objective of this thesis is to examine the sequential validation process and influencing factors that contribute to the facility attaining agency approval. A comprehensive review of the available literature indicates that projects regularly fail to meet their regulatory objectives due to the building provider and client's differing understanding and views of the validation process and of GMP. From this literature a validation model is derived and proposes that the design, installation and operation stages of the validation activity are time-series dependant sub-processes controlled through sensing, feedback and comparison. The research was largely qualitative, case-study based and used an interpretivist approach to analysis, which relied on participant observation and grounded theory techniques. Additional, external validation of the model was sought by collecting and analysing empirical data from an industry questionnaire The results of the study demonstrate that significant deviations between the model and the data exist and measures to construct compliant pharmaceutical buildings are often underdeveloped and result in unsuccessful project outcomes. The criteria by which the success of any construction project is judged are normally time, cost and quality. Time and cost are readily measurable, but the meaning of quality, in relation to the validation activity, can be more elusive and this is at the root of the problem of successful validation of pharmaceutical buildings.

Stabilised-soil cement building blocks are an established building material in many areas of the Less Developed World. This thesis has been split into three parts. Part A presented an overview of the process of soil-stabilisation and outlined the roles which soil structure and curing play in stabilisation. It examined methods of testing soils, highlighting errors presented in the published literature and presenting corrected testing procedures and unified plans for their implementation. Part B examined the conventional quasi-static block compaction process (slowly applied pressure) and established that no cost-effective increase in the compacted block density can be achieved by altering such moulding configurations as mould-wall roughness, mould-wall taper, number of applied pressure cycles and double-sided pressure application. The tests were also used to assess the plausibility of several theoretical mechanisms underlying quasi -static compaction. Cement may be traded against compaction pressure for a given final cured strength. The relation of compaction pressure and cement content to well-cured strength was established for 50 mm diameter cylinders and used to assess the financial benefit of high-pressure compaction. It was shown that savings in the cost of cement associated with high-pressure compaction were outweighed by the additional cost of such machinery. However there were additional benefits found to high-density compaction, beyond the saving in stabiliser costs. It was established that a highdensity moulding machine in the range £1000 - £1500 would allow these benefits to become cost competitive. Part C examined both experimentally and theoretically an alternative dynamic (impact blow) compaction process, establishing that optimised dynamic compaction may produce strength equivalent to quasi-static high-density moulding while requiring only 25-50 % of the energy. Five theoretical models of the process were developed and the Combined Airlock/Friction/Compression Wave Model was shown to have the most explanatory power.

This study is concerned with the convective heat transfer, due to the action of the wind, from the upper surface of roof mounted flat plate solar collectors. The ability to predict the quantity of heat transferred from a collector, in this manner, is necessary in order to facilitate the evaluation of the overall efficiency of a collector panel. Previous methods of determining this convection coefficient have generally relied upon extrapolations of small scale wind tunnel results to full-scale values. The validity of these methods is questionable, and it was found that there was a lack of full-scale data relating to the convection coefficient from the upper surface of a flat-plate collector. It was also found that no systematic attempt to relate model results to full scale values had been made. Full-scale experiments have been performed to evaluate the convective heat transfer coefficient, h, from the upper surface of a roof mounted flat plate. The convection coefficient was found to be dependent upon the wind speed as measured above the roof ridge line, V 6R, and to some extent upon the direction of the prevailing wind, G. Relationships between h and V 6R are presented, as are relationships between h and VH (the wind speed measured at the mid-panel height) and h and V 10 (the meteorological 10m wind speed). Small scale wind tunnel experiments were also performed. This was in order to assess the potential of using wind tunnel model results to predict accurately full-scale convective heat losses. These experiments showed some qualitative agreement with the full-scale tests. However, extrapolation of these model results to full-scale values rendered heat transfer coefficients in excess of those found in the full-scale work. Therefore the use of previously derived full-scale results from wind tunnel studies must be treated with caution. It is suggested that the full-scale results, presented here, represent a more satisfactory means of evaluating the convective heat transfer from the upper surface of roof mounted flat plate solar collectors.

This thesis is concerned with the analysis of building frames acting compositely with infilling wall panels. The significance of the composite action is emphasized and previous work on infilled frames is reviewed. The existing methods of analysis are categorized and their analytical assumptions are highlighted. It is concluded that more accurate results may be obtained from the development of a non-linear finite element analysis. The finite element method is reviewed and new elements for representing beams, interfaces and loading are developed. Failure criteria for concrete under multiaxial stress and also failure criteria for masonry under uniaxial compression are developed. The non-linear elastoplastic behaviour of concrete is modelled using the concept of equivalent uniaxial strain and the model is extended for cracked materials. Elastoplastic models are also developed for ductile materials(steel) for secant and incremental changes of stresses and strains. These models and the newly developed elements are incorporated into the finite element analysis which is numerically implemented by a new computer program, NEPAL. A number of steel frames with concrete inf ills covering the practical range of beam, column and infill strengths and also wall panel aspect ratios, are analysed using this program. The finite element results are compared with the predictions of a range of existing methods of analysis and their limitations are discussed in detail. A new method of hand analysis is developed, based on a rational elastic and plastic analysis allowing for limited ductility of the infill and also limited deflection of the frame at the peak load. The new method is shown to be capable of providing the necessary information for design purposes with reasonable accuracy, taking into account the effects of strength and stiffness of the beams and columns, the aspect ratio for the infill, the semi-rigid joints and the condition of the frame-infill interfaces (co-efficient of friction and lack of fit). It is concluded that simple and economical design approaches can be established for frames with infilling walls.

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This study considered the design, development and testing of a new type of reinforced grouted cavity clay brickwork beam, the University of Plymouth Quetta Style Beam (the "Beam"). Under experimental load, the beam format results in asymmetric, non-linear, elastic bending and shear stress contours. This is contrary to beam behaviour acknowledged, in the codes, for reinforced brickwork and other structural materials. A suggested hypothesis is "evidence has been produced of excessive tensile stress beyond the steel yield stress, which may or may not be due to brick tensile strength". This hypothesis is based on a relatively small sample and upon the determination of the neutral axis depth which depends on the shape of the compressive stress diagram. It is suggested that this hypothesis is worthy of further experimental investigation and analysis. The Beam has enhanced flexural strength when compared with beams reinforced in the bed joints and with some grouted cavity reinforced brickwork beams, studied so far. Tests on and analysis of brickwork prisms showed that the Structural Code for Reinforced Masonry, BS 5628-2- 2000, recommends extremely conservative design strengths, particularly when perforated bricks are used. It is further suggested the Code does not fully recognize the potential strength of brickwork. In this study 54 beams were built; reinforced and unreinforced in shear. Every beam was replicated three times and three brick types and three different spans were used. An important aspect of the Beam is the bonding of the outer leaves of brickwork with the grouted core. Bricks in the compression zone were loaded in their weaker directions. Vertical pockets of grout, incorporated into the Beam design, allow easy provision of shear links. The bonding format and integrated system is not detrimental to the flexural resistance of the Beam but produces a compressive stress diagram, at ultimate load, which does not conform to the parabolic curve used in reinforced concrete and in symmetrically reinforced brickwork beams. This is perhaps a more realistic model for reinforced clay brickwork. Beams were analysed using elastic and limit states theories. A 30 Finite Element Analysis (FEA) showed, possibly for the first time, the complex, asymmetric, non-linear, elastic stress contours which develop in non-traditionally bonded brickwork. Equations are proposed in this study which would enable the depth of the Beam to be selected to resist an applied bending moment and also, if confirmed by further studies, a method to incorporate the excess tensile force into the analysis of the section capacities and to ascertain the neutral axis depth. The Beam was used on five construction sites on and off campus. These performed well. It was identified that: the characteristic compressive strength of non-traditionally bonded brickwork should be obtained by the use of prism tests, when an accurate economical design is required; significant loss of the potential characteristic strength of perforated and solid clay brickwork is due to the use of a bonding material whose basic strength is less than the compressive strength of the brick. A study is needed to identify an improved bonding material for an structural brickwork.