FEM analyses have been performed on simply reinforced concrete elements to study the influence of the properties of cracks and the quantity of reinforcing bars upon the shear transfer behaviors in cracks of concrete. The discrete crack models were adopted in the analysis and the simple models that consist of a dilatancy crack and/or a frictional crack in addition to reinforcement were used to make the effects of crack surfaces and reinforcing bars clear. The properties of cracks corresponding to the smooth and rough crack surface were considered by using different aggregate sizes to evaluate interlocking for a dilatancy crack. Furthermore, the coefficient of friction and dilatancy for Coulomb criteria were estimated based on experiments to evaluate sliding behaviors in cracks. The meaningful relations among shear transfer behaviors in cracks, the properties of cracks and the quantity of reinforcing bars have been proven by extensive parametric analyses.
