Flexural strengthening of reinforced concrete beams with pre-stressed near surface mounted CFRP systems

Abstract

This study investigated the effectiveness of strengthening reinforced concrete (RC) beams with pre-stressed near surface mounted (NSM) carbon fiber reinforced polymer (CFRP) systems was investigated. Eight RC beams were tested under four-point loading tests. An un-strengthened control beam was used for reference. Four beams were strengthened with pre-tension NSM CFRP bars. The last three beams were strengthened with post-tension NSM CFRP bars. The test results showed that strengthening with a pre-stressed NSM beam enhanced the flexural behavior of the beam compared to that of the control beam. The post-tension NSM systems provided the best enhancement to beam performance for the concrete cracking, steel yielding, and ultimate loads. The test results of post-tension NSM beams were compared with the finite element analysis (FEA) model to validate the proposed model. The reinforcement length and pre-stressing force were used as parameters to analyze the effects of the strengthening performance in the proposed numerical model.