Abstract
The fracture mechanism of concrete has been investigated using the tension softening properties obtained by fitting the measured load-displacement curves in bend tests on single edge notched beams. The effects of notch depth, loading rate, maximum aggregate size, water/cement ratio, four-point bending, curing and age upon the tension softening properties are discussed. The tension softening properties can provide valuable information about the difference in the fracture mechanism between mortar and concrete, between low and high water/cement ratio, etc. Furthermore, by comparing the results of the numerical calculations using the softening model with those of the slow crack propagations observed by 50X microscopes during tests, the validity of the model and the fracture mechanism in the softening zone are investigated.
