Wedge splitting test on fracture behaviour of ultra high strength concrete

摘要

The fracture behaviour of ultra high strength concrete (UHSC) with axial compressive strength more than 140 MPa is presented in this paper. Based on the wedge splitting tests with six cubical specimens, the fracture behaviour of UHSC with and without coarse aggregates is investigated. The common fracture mechanical parameters such as fracture energy, crack opening displacement (COD), the characteristic length and the fracture toughness by non-linear fracture mechanics (NLFM) theory are experimental determined. Through finite element analysis with suggesting linear and bilinear models for closing force sigma(W) vs. crack width with regard to the wedge splitting tests, the relationships between splitting force and COD are simulated and verified with the tested ones. It is concluded that the COD, characteristic length and fracture toughness of UHSC can be improved obviously with the contribution of coarse aggregates.