Investigation on concrete-PCM interface under elevated temperature: At material level and member level

This paper summarizes the experimental and analytical investigation on performance of polymer cement mortar (PCM)-concrete interfaces and PCM overlaid reinforced concrete (RC) beams at temperature level of 20, 40 and 60 °C. At material level, bonding were tested by conducting interfacial split tensile strength test and bi-surface shear strength test. At member level, bonding was tested by conducting four point bending test of RC beam strengthened by overlaying with PCM on tension faces. Temperature showed significant effects on both levels of tests and reduction in strengths were observed with increase in temperature. Prediction formulas for interfacial strengths of materials were proposed and verified at all temperature levels. Ultimate shear loads and failure modes were analytically calculated by the truss model approach and were compared with experimental observations. Very close correspondences were observed at temperature of 20, 40 and 60 °C.