Complex multilevel fracture tests of concrete: basic mechanical fracture parameters of standard size specimens.

Abstract

The aim of the current research is to develop a complex multilevel approach for experimental–computational determination of mechanical fracture parameters of concrete as a typical quasi-brittle material. This includes testing, advanced evaluation and soft computing-based identification of specimens of multiple sizes in multiple test configurations and analyses of fracture processes using multiscale modelling approaches. The evaluation of the part of an extensive experimental program is presented in this paper. The basic mechanical fracture parameters of investigated concrete determined on the standard test specimens with nominal dimensions of 100 × 100 × 400 mm subjected to the standard three-point bending fracture test are introduced. The results of three different sets of specimens provided with different depths of the initial notch are compared in terms of the absolute values of the selected mechanical fracture parameters. The results indicate different sensitivity of the particular mechanical fracture parameters to the depth of the initial notch.