Rate Effect, Size Effect and Nonlocal Concepts for Fracture of Concrete and Other Quasi-Brittle Materials

Abstract

The lecture reviews several recent results achieved at Northwestern University in the problem of size effects and nonlocal concepts for concrete and other brittle heterogeneous materials, and presents a new method for calculating the load-deflection curves of fracture specimens or structures with time-dependent crack growth and viscoelastic material behavior. The results reviewed deal with the size effect law in fracture and its exploitation for determining material fracture characteristics, statistical generalization of the size effect law with a nonlinear reformulation of Weibull’s weakest-link theory, determination of the size dependence of the fracture energy determined by work-of-fracture method, nonlocal models for smeared cracking and damage, microstructural determination of the nonlocal material properties and fracture process zone behavior, size effect in fatigue fracture of concrete, and use of the size effect for determining the fracture properties of high-strength concrete.KeywordsFracture EnergyLinear Elastic Fracture MechanicFracture Process ZoneHigh Strength ConcreteNormal Strength ConcreteThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.