The use of Wire Mesh-Polyurethane Cement (WM-PUC) composite to strengthen RC T-beams under flexure

This paper presents the experimental behaviours of reinforced concrete (RC) T-beams strengthened using an innovative technique, namely, wire mesh-polyurethane cement (WM-PUC) composite. The flexural behaviour of WM-PUC-strengthened beams was investigated. This investigation considered three parameters: the amount of wire mesh used, the material into which the wire mesh was embedded, and the loading method. All beams were tested in a four-point bending setup. The test results indicated that relative to ferrocement-strengthened beams, the WM-PUC-strengthened beams exhibited significantly greater yield loads, ultimate loads and stiffnesses, and these enhancements increased with an increasing number of layers of wire mesh. Relative to ferrocement strengthening, WM-PUC strengthening was found to more effectively hinder crack expansion, mainly because no cracks appeared on the PUC surface after the concrete cracked until its failure. After strengthening with WM-PUC laminate, the decreased stiffness of a pre-cracked beam was not as easily detectable in the early stage relative to that of a non-preloaded beam. The good bonding performance of the PUC in the WM-PUC laminate indicated that no additional bonding aid is needed in WM-PUC-strengthened beams. These results demonstrate that WM-PUC strengthening shows potential as an external strengthening technique for concrete structures.