Shrinkage cracking of fiber reinforced concrete

Tests were conducted using a ring-type specimen to simulate restrained shrinkage cracking. The effects of two type of fibers (steel and polypropylene differing amounts of fibers (0.1 to 1.5% by volume); age of concrete (2 hr or 4 days); and length of drying (up to 6 weeks) under a given environment (40% relative humidity and 20 C (68 F)) were studied. The results were satisfactorily compared with a theoreticl model developed by the authors.