Two-Parameter Fracture Analysis of Wedge Splitting Test Specimens

摘要

The subject of the contribution is to gain new aspects of knowledge about thernfracture behaviour of cementitious building materials by the wedge splitting testrn(WST). Particular attention is paid to the accurate description of the near crack-tiprnstress field in the WST specimen influenced particularly by the bottom boundaryrncondition of the test inducing a vertical compressive force to the bottom part of thernspecimen in the area where the fracture is assumed to be propagating. To this aim arntwo-parameter constrained-based fracture mechanics is used. Different levels ofrnconstraint in the vicinity of the crack tip during fracture process through thernspecimen ligament are characterized by means of the T-stress. Attempts are made tornconsider even more than the two members (i.e. K-factor and T-stress) of thernWilliams’ series approximating the stress field in the cracked body. The problem isrnsolved numerically by means of the finite element method and results are comparedrnwith data taken from the literature.