Creep behavior of a SFRC under service and ultimate bending loads

Abstract

A research project was carried out to evaluate the flexural creep behaviour of SFRC beams under sustained service loads and the crack propagation under high sustained loads. The evolution of the deflection, the crack width and the crack propagation were measured in service conditions (CMOD ws = 0.1 mm, load level P/Ps = 60%) and ultimate conditions (wu = 0.5 mm, P/Pu = 60–90%). The results allowed assessing the impact of the initial CMOD and sustained load levels on creep, crack propagation, damage evolution, and the mechanisms leading to the rupture of the beams. In service conditions, the results show that the deflection and crack opening of SFRC beams under sustained loading stabilises quickly toward an asymptote and that the compliance remains constant. In ultimate conditions, the results show that crack propagation governs the failure mechanisms of SFRC beams subjected to high sustained load levels. Moreover, it was observed that the beams failure occurs when the state of damage defined by the static behaviour envelope is attained.