Shaking table tests of a half-scale 2-storey URM building retrofitted with a high ductility fibre reinforced concrete overlay system

Abstract

The dynamic response and seismic behavior of unreinforced masonry (URM) buildings retrofitted with high ductility fibre reinforced concrete (HDC) overlay is investigated in this study. The HDC is a class of fibre-reinforced cementitious composite with tensile strain-hardening behavior and high compressive strain abilities. 17 shaking table tests, divided into three phases, were conducted on a half-scale two-storey URM model building. In phase I, testing was performed on the model without any retrofitting until it reached a near-local-collapse state. The damaged model was retrofitted with welded wire reinforcement (WWR) and tested in phase II. The model was retrofitted again with an HDC overlay for the tests in phase III. The comparisons between the WWR and the HDC overlay were analysed regarding the natural frequency, drift response and base shear. Backbone curve, torsion effect and seismic behavior evaluations were also conducted for the model retrofitted with the HDC overlay. The experimental results indicated that the HDC overlay retrofit system is more effective in improving seismic behavior than WWR overlay. The model that was retrofitted with the HDC overlay exhibited clear enhancements in shear capacity and damage tolerance.