The experimental performance together with the theoretical predictions of strains and deflections of thin fibre cement corrugated sheets are principally reported in this thesis. Existing theories of tensile behaviour of fibre reinforced cement are reviewed. Asbestos cement and alternative fibre reinforced cement technologies associated with these sheeting materials are discussed. Asbestos cement and polypropylene network reinforced cement corrugated sheeting have been tested under a variety of loading regimes and support conditions. Asbestos-free commercial products have also been tested. Finite element analyses based on the LUSAS system have been used to predict the shape of the uncracked load- deflection curves and deflection and strain profiles of various corrugated sheets with different geometrical profiles. Wetting and drying tests on uncracked asbestos cement and polypropylene network reinforced cement sheets have been carried out and a prediction made using the Lusas program of the warping stresses caused by moisture gradients. A new approach has been developed to predict the load-deflection curves and deflection profiles of semi-cracked and severely cracked polypropylene network reinforced cement sheets under various loading regimes. In this approach, cyclic loading characteristics of the tensile specimens were used to estimate the elastic moduli of the cracked composite for various numbers of cracks at two different load levels. Generally, the theoretical predictions show good agreement with the experimental results for uncracked and cracked sheets and hence the mathematical models could, with confidence, be used to assess the performance of a range of corrugated sheeting with various loading configurations.

Foamed concrete is produced by combining foam and slurry thus entrapping numerous small bubbles of air in the cement paste or mortar. The density of foamed concrete is a function of the volume of foam added to the slurry and the strength decreases with decreasing density. In this study the effect on the properties of foamed concrete, of replacing large volumes of cement with both classified and unclassified fly ash (pfa) was investigated. The casting densities of the materials used in this investigation varied between 1000 and 1500 kg/m3 and 50%, 66.7% and 75% of the cement (by weight) was replaced with pfa. The properties measured included compressive strength, dry density, porosity, permeability, water absorption, drying shrinkage, elastic deformation, creep, and void size distribution. The use of high volumes of unclassified ash did not appear to have any significant detrimental effects on the measured properties of the foamed concrete. Although the rate of gain in strength was reduced by the use of large volumes of ash, up to 67% of the cement can be replaced by ash without any significant reduction in, the long-term strength. The permeability increased with increased air content but the water absorption did not appear to be influenced by the volume of air entrained. The elastic modulus of foamed concrete reduced while the creep increased with reducing density. The drying shrinkage of foamed concrete does not seem to be a function of density and the shrinkage values were similar to those of cement paste with similar water/binder ratios; these values were between two to three times greater than those of conventional concrete. An increase in ash content lead to a slight reduction in the drying shrinkage. A mathematical model was developed relating the compressive strength of the foamed concrete to age, porosity and ash/cement ratio.

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