EVALUATION OF FATIGUE AND DURABILITY PROPERTIES OF E-GLASS FIBRE REINFORCED PHOSPHATE CEMENTITIOUS COMPOSITE

摘要

This paper describes experiments on random E-glass fibre reinforced phosphate cement laminates under repeated load. A sandwich panel composed of two E-glass fibre reinforced cementitious faces and a weak (or mixed) core is investigated as a possible application. Repeated loading appears to influence both the stiffness properties and the failure stress in a considerable way. These properties are important to ultimate limit state design since the panels are used as construction elements. The face in tension is most affected by repeated load. Therefore it is essential to investigate the behaviour of the laminates under repeated tensile load. The effects of repeated tensile load on the failure stress and the stiffness of random reinforced cementitious laminates are presented and discussed. The number of loading cycles can thus be introduced as a design parameter. Also the influence of repeated mechanical load on the stiffness properties is studied. This can be implemented in serviceability limit state design. The paper further describes the degradation of the laminates due to cyclic environmental (outdoor) conditions such as repeated exposure to rain and sunshine. The results from the described experimental wetting-drying cycles are also necessary in design procedures.