The relationship between local bond splitting behavior and average ones in reinforced concrete members has not been clear, yet. As the first step to make clear this problem, local bond behavior in case of no lateral reinforcement is discussed based on the study by Tepfers. In this study, bond stress, τ_b, is provided as the function of internal crack depth, rt, and angle between the principal bond stress and the axis of the reinforcement, α. The bond splitting test is carried out using new-designed specimens. Test results show that the value of α is assumed to be 34 degrees, and r_i has a proportional relationship with slippage of reinforcement, s. Using these results, a new relationship between τ_b and s is proposed.
