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Two liquid composite moulding techniques have been investigated in this study, resin transfer moulding (RTM) and resin infusion under flexible tool (RIFT) for the processing of glass fabricepoxy laminates with 5% nanoaggregates of silica nanoparticles in the epoxy matrix. It has been found that the high fibre fraction reinforcement (V f 50 . 50) filters the silica nanoaggregates resulting in stopping the in plane resin infiltration in RTM right at the beginning of the filling stage. Laminates of lower fibre fraction (V f 50 . 40) were produced successfully by RIFT. Dynamic mechanical thermal analysis (DMTA) and three point bend tests showed that fibre-silica-epoxy composites, processed by RIFT, had higher elastic shear modulus and interlaminar shear strength than conventional fibre-epoxy composites manufactured by the same RIFT process.

Full scale tests have been carried out on lengths of unrestrained and restrained plain and jointed distribution pipe sections (~4" internal diameter) in order to investigate the strains and loads generated in cast iron water distribution mains as a result of temperature fluctuations. Tests on unrestrained sections enabled the co-efficient of thermal expansion of the pipe material to be measured. In a fully restrained situation, which can occur in a pipe section in service when the joints are locked, tensile stresses arise from a decrease in temperature (in accordance with the predictions of a simple one-dimensional model) and it is shown that these stresses are sufficiently high to fracture a corroded pipe. In situations where the tensile stress leads to joint slippage, leakage through the joint is observed. Water leakage was also observed through the wall of corroded pipes that retained sufficient structural stability to carry load without failure.

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