ABSTRACT

The effect of using fibres to control cracking due to restrained shrinkage in large concrete members is investigated experimentally. A total of 44 specimens were tested representing sections of square columns 400x400mm with thick steel cores providing the internal restraint. Four types of fibres were used, namely: straight, hooked and flat steel fibres, and nylon fibres. The fibre content, core diameter and specimen height were varied. Observations were continued for nearly 18 months. The inclusion of fibres resulted in significant reductions in shrinkage and cracking, particularly with the steel types.