Performance of very-high-strength concrete subjected to short-term repeated loading

Abstract

The effect of short-term repeated loading on very-high-strength concrete prisms of various sizes has been experimentally investigated. Concrete batches made of local materials were cast using different types of coarse aggregate. The level of cyclic preloading was altered and the corresponding influences on the ultimate strength, strain and modulus of elasticity were monitored. The effect of changing the number of cycles at a certain preloading level was investigated. For certain loading levels the number of cycles to failure was observed. The size of the specimens tested was noted to have a significant effect on the stress–strain parameters. Behavioural modelling using the concepts of continuous damage mechanics was conducted. On the basis of the experimentally observed behaviour, a mathematical expression for the damage variable was derived. Simulation by the proposed damage model captured most of the salient features of the response such as the effect of cyclic preloading at different levels, the number of cycles to failure in fatigue tests and the stress–strain curves.