Triaxial test results of high-strength concrete subjected to cyclic loading

Abstract

High-strength concrete (HSC) has highly desirable structural engineering properties, which can lead to significant cost savings in heavily loaded concrete structures. However, its use is limited by a concern regarding an increased brittleness compared to normal strength concrete (NSC), especially under complex multi-axial loading conditions. The issue of ductility is extremely important in structures subjected to earthquake loading conditions. In order to determine the lateral confinement required for a given level of ductility, the relationship between axial stress and lateral strain of confined HSC needs to be established. This paper describes a testing programme carried out to obtain the relationships between axial stress, axial strain and lateral strain for HSC under cyclic loading and subjected to constant lateral confining pressures. Compressive strengths of concrete tested were 40, 60, 80 and 100 MPa. Uniform confining pressures applied were 4, 8 and 12 MPa. The experimental results are presented and the effects of cyclic loading and confinement on the constitutive behaviour of HSC are described.