Author

KONTHESINGHA, C.1; MASIA, M.2; PETERSEN, R.3; MOJSILOVIĆ, N.4;
SIMUNDIC, G.5; PAGE, A.6

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, 1200mm x 1200mm, 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.
Keywords: Masonry, strengthen/retrofit, cyclic in-plane shear, NSM, FRP