SEMI-ANALYTICAL SOLUTION OF DOUBLE-K FRACTURE PARAMETERS OF THREE-POINT BENDING CONCRETE BEAMS USING SUB-DOMAIN BOUNDARY ELEMENT METHOD

摘要

The fracture failure process of concrete structures is effectively evaluated by the so-called double-K fracture parameters, i.e. the initial fracture toughness and the unstable fracture toughness. The values of the double-K fracture parameters can be calculated based on the crack mouth opening displacement (CMOD) and the crack tip opening displacement (CTOD) from a semi-analytical method. Using sub-domain boundary element method, the fracture failure of three-point bending concrete beams is simulated, and the values of the CMOD and the CTOD can be easily obtained. The double-K fracture parameters of three-point bending concrete beams with initial notch are analyzed using the presented method and the accuracy of the numerical results are assessed by the experimental results.