Concrete Fracture in CLWL Specimen

Results are reported of a series of tests on concrete crack‐line wedge loaded double cantilever beams. Those tests provide a data base for fracture parameters characterizing mode I cracking in concrete. The development is reported of a replica technique that provides an easy and accurate method for determining the total extent of cracking in concrete specimens, and it is shown that the fracture process zone, which can be determined with that technique, continues to increase in length with increasing load. From analysis of the results, it is concluded that linear elastic fracture mechanics techniques are not suited to predicting unstable cracking in concrete members of the proportions normally used in buildings.