Author(s)

D. Meštrović, I. Ivić, D. Čizmar

Abstract

The loading rate significantly influences structural response. The structural response depends on the loading rate through three different effects: through the creep of the bulk material between the cracks, through the rate dependency of the growing microcracks and through the influence of structural inertia forces. The first effect is important only at extremely slow loading rates whereas the second and third effects dominate at higher loading rates. In this paper, a rate sensitive model, which is based on the energy activation theory of bond rupture and its implementation into the microplane model for concrete are given. To investigate the importance of the rate of the growing microcracks and the influence of structural inertia, static and dynamic analyses were carried out. The results show that with an increase of the loading rate, the pull-out resistance increases. The comparison between model prediction and test data for uniaxial compression failure of concrete shows that the model realistically predicts the influence of the loading rate on the compressive strength and initial Young’s modulus.

Keywords

concrete, concrete cone failure, finite element analysis, rate sensitivity, microplane model, crack band approach