Experimental and probabilistic analysis of the crack propagation in fiber reinforced concrete

Abstract

Concrete possesses good resistance to compressive stresses; however, it remains weak in resisting tensile stresses, making the formation of cracks in concrete members inevitable. The concrete’s durability is directly affected by the development of cracks, which are a direct pathway for deterioration agents that damage the concrete elements. Consequently, the reinforced concrete can experience corrosion, spalling, loss of strength, or progressive disintegration. One way to avoid such problems is to incorporate discrete fibers into the concrete matrix. The fibers act by bridging the gaps formed by cracks, thus, slowing down the crack-opening and propagation process. Studying the crack formation and propagation in the presence of material and geometric uncertainties is impossible using deterministic approaches. In the present paper, the crack propagation in fiber reinforced concrete (FRC) beams is studied from a probabilistic perspective considering the formation and propagation of cracks as a stochastic process. A multinomial Random Walk model is developed based on experimental data on steel fiber reinforced concrete beams. The model is then used to investigate the behavior of crack paths in the presence of discrete fibers considering different scenarios. Inferences are made based on the simulations done through the proposed model to establish a framework to determine the probability of failure of FRC beams. The findings of this study are useful to engineers inspecting existing members and in the design of new members by considering the probability of failure due to crack propagation as the design objective.