ANALYTICAL PREDICTION OF CRACK RESISTANCE IN CONCRETE

Abstract

Concrete is considered to be a heterogeneous material consisting of different phases comprising of aggregate, matrix and weak interfacial transition zone. Concrete has pre-existing microcracks in it and has quasi-brittle behavior. Concrete is different from ideal brittle materials because it has non-linear behavior in inelastic zone around the propagating crack. Fracture process zone is the result of this non-linear phenomena in concrete. The fracture zone governs the complete fracture behavior of concrete. Fracture process zone in concrete is complex due to various toughening mechanisms such as microcrack shielding, aggregate bridging, crack blunting etc. The aim of this work is to understand the mechanism of formation and propagation of fracture process zone. Using the various numerical approaches, various fracture parameters like stress intensity factor and crack extension resistance has been determined, analyzed and compared under static and fatigue loading.