The target of this study is to investigate the behavior of concrete confined externally by pre-stressed steel straps when subjected to concentric load. Few parameters were studied with their effect on the response of confined concrete. The cross section shapes whether circular or rectangular and the developed confinement effect for each figure were considered. The configuration of the confining straps at the corners of prismatic concrete element was accounted in the research. Also, the spacing between the straps and its effect on the homogeneity of concrete confinement and the corresponding compressive strength was included, too. Last, the behavior of concrete when loaded at smaller width/area than its original geometric configuration was examined in the study. Thirty-four concrete specimens were tested to conduct the process of the research.