This paper presents the differences in growth of time-dependent strain values in reinforced cement concrete (RCC) and\r\npre-stressed concrete (PSC) flexural members through experiment. It was observed that at any particular age, the time-dependent\r\nstrain values were less in RCC beams than in PSC beams of identical size and grade of concrete. Variables considered in the study\r\nwere percentage area of reinforcement, span of members for RCC beams and eccentricity of applied pre-stress force for PSC\r\nbeams. In RCC beams the time-dependent strain values increases with reduction in percentage area of reinforcement and in PSC\r\nbeams eccentricity directly influences the growth of time-dependent strain. With increase in age, a non-uniform strain develops\r\nacross the depth of beams which influence the growth of concave curvature in RCC beams and convex curvature in PSC beams.\r\nThe experimentally obtained strain values were compared with predicted strain values of similar size and grade of plane concrete\r\n(PC) beam using ACI 318 Model Code and found more than RCC beams but less than PSC beams.
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