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.

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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.

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It is argued that a fundamental criterion which has received little consideration in the investigation of cost prediction is the impact of information upon accuracy. An information model is developed by drawing on the work of communication engineers, information scientists and psychologists. It is then demonstrated that information cannot be divorced from the knowledge of the receiver and as such it then becomes necessary to determine how knowledge is accumulated and how this then impacts upon the need and demand for information, the choice of relevant information, as well as how that information is utilised. The concept of relevance is considered from a logical and psychological perspective. On completion of this analysis the information model which links cost estimating with entropy, information and knowledge is completed. It is argued that the developed model is comprehensive and facilitates the progression of research in this field. The model is then used as a basis for the investigation of the relationship between information and expertise in estimating, choice of information for estimating, impact of information on estimating, perceptions of information quality and the perceptions of the importance of information facets and attributes to the estimating process.

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