Fatigue crack growth analysis of fiber reinforced concrete with effect of interfacial bond degradation

This paper presents an analytic model for fatigue crack life prediction in fiber reinforced concrete (FRC). The model elucidates fatigue crack growth in cementitious matrix material under the influence of external cyclic load and fiber and aggregate bridging If is shown that fiber-matrix interface damage must be accounted for in order to properly simulate the three experimentally observed stages of matrix crack growth, involving a decelerated stage, a steady state stage, and an accelerated stage towards final fracture failure. This model, which explicitly accounts for the positive role of fibers on fatigue life, predicts the existence of the well-known fatigue limit load in standard S-N curve tests of FRCs. The basic framework of this analysis can be used to address fatigue life of FRC structures subjected to high cycle fatigue loading, as well as providing a basis for material design of fatigue resistant FRC at the microstructure level. (C) 1998 Elsevier Science Ltd All rights reserved.