Investigation of bond behaviour, crack pattern, crack spacing and ultimate bond strength for reinforced concrete members under uniaxial tension is very important in analysis and design of RC structures. This paper summarizes the result of an experimental project aimed at improving the current understanding of the response of cracked concrete. For this purpose a comprehensive experimental program including reinforced concrete cylanders with different concrete covers and reinforcement ratios is conducted. All specimens tested under direct uniaxial tension. The axial forces were increased to reach yielding capacity of the steel reinforcements; by the onset of plastic deformations, the tests were creased and the number of transversal cracks and minimum and maximum crack spacing were recorded for each specimen. The bond stress between the reinforcing steel and the concrete were evaluated using equilibrium equations for a crack spacing portion. Clear concrete cover, reinforcement diameter and reinforcement ratio are the main parameters considered in this investigation

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