关键词: 混凝土, 循环孔隙水压, 动态抗压, 应变速率, Weibull-Lognormal模型

Abstract: The mechanical properties of concrete subjected to cyclic pore water pressure are studied via dynamic and static triaxial loading tests using 10 MN large multifunctional hydraulic servo instrument. Weibull-Lognormal model and standard-recommended model were used to fit and analyze the stress-strain curves. Test results revealed that in the presence of cyclic pore water pressure, concrete strength decreased apparently under quasi-static and low strain rate loading, while augmented under high strain rate. However, higher loading rate had little effect on the peak strain of concrete. With the increase of loading rate, the peak strain of concrete increased. The elastic modulus of concrete undergone cyclic pore water pressure was higher than that in the absence of cyclic pore water pressure. In the meantime, with the climbing of strain rate, elastic modulus increased also. The full stress-strain curve of concrete can be well fitted by using Weibull-Lognormal model and standard-recommended model, of which the former has better fitting effect in descending segment than the latter does

Key words: concrete, cyclic pore water pressure, dynamic compressive behavior, strain rate, Weibull-Lognormal model