A comparative study of fracture parameters in notched concrete beams

Abstract

Synopsis The paper compares a number of fracture parameters, both linear and non-linear, obtained from the results of tests carried out on notched concrete beams with depths varying from 100 to 800mm. The parameters were critically investigated, for their ability to describe concrete fracture. The concept of a ‘fracture process’ is introduced. The type of, fracture process as well as the existence of an extensive microcracked zone ahead of the main crack critically affect values of the measured parameters. It was concluded that none of the existing parameters are entirely satisfactory, due primarily to a lack of true size-independence in the relationships. Parameters must he linked to fracture processes, which, together with the presence of the microcracked zone, implies that ultimately a number of non-linear parameters will suit the concrete fracture problem best.