A numerical model for the time-dependent cracking of cementitious materials

A unified finite element formulation is presented for the analysis of the t ime-dependent cracking of cementitious materials. The rate-type constitutiv e law incorporates linear visco-elasticity and continuum plasticity. The fo rmer accounts for the bulk creep via a Maxwell chain, while the latter desc ribes crack initiation and propagation via a softening, anisotropic Rankine yield criterion. The rate dependence of bond ruptures leading to fracture is accounted for by considering the viscosity of the cracking process. This contribution to the cracking resistance also regularises the localisation. process. It is demonstrated how other important phenomena in cementitious materials, such as stress-dependent hygral and thermal shrinkage, can be in corporated into the computational framework. Copyright (C) 2001 John Wiley & Sons, Ltd.