Author
KONTHESINGHA, C. and MASIA, M. and PETERSEN, R
The University of Newcastle, Centre for Infrastructure Performance and Reliability
MOJSILOVIC, N.
Institute of Structural Engineering, ETH Zurich, Switzerland
SIMUNDIC, G. and PAGE, A.
The University of Newcastle, Centre for Infrastructure Performance and Reliability

Abstract
An experimental study was conducted to assess the effect on strength and ductility of retrofitting unreinforced masonry (URM) shear panels with near surface mounted (NSM) fibre reinforced polymer (FRP) strips. A total of six wall panels, 1200 mm x 1200 mm, were subjected to vertical precompression combined with increasing reversing cycles of in-plane lateral displacement. The panels were tested first as URM, retrofitted with NSM FRP strips and then retested. The URM testing was conducted as part of a previous research study to investigate the effects of a damp proof course (DPC) layer incorporated near the base of the panels. The six panels failed in compression, with crushing at the corners and near-vertical cracking throughout the panels in the URM tests. For the current study, the panels were retrofitted using three different arrangements of FRP strip reinforcement and then retested using the same apparatus but with base sliding at the DPC level prevented. The tests were used to determine the effect on strength, displacement capacity and ductility achieved by FRP retrofitting the damaged URM panels compared to the original undamaged panels. The broader aim of the research is to identify techniques for improving the seismic performance of existing URM walls under in-plane shear loading.

Key words
Masonry, strengthen/retrofit, cyclic in-plane shear, NSM, FRP