Abstract:Based on the three-point bending beam fracture tests on the crumb rubber concrete with different specimen geometries and rubber volumes, the experimental curve of the whole fracture crack process was obtained, and the fracture energy and K-R resistance curve were studied. Through the digital image correlation method, the whole field displacement and strain distribution perpendicular to the direction of crack propagation were determined,from which the crack propagation and evolution process of fracture and damage can thus be examined. The results indicate that the fracture energy displays an increasing tendency with specimen geometry and rubber volume. The K-R resistance curve reveals the size effect by change of specimen geometries and shows no indicative relationship with 0%~14% rubber volume which was designed in this study.