In-Plane Shake-Table Testing of GFRP-Strengthened Concrete Masonry Walls

In-plane shake-table tests were performed on eight full-scale unreinforced concrete block walls. Three of the walls were left as plain unreinforced masonry and five were strengthened using glass-fiber-reinforced plastic (GFRP) strips in four different configurations. All walls were first subjected to design-level earthquake records to determine the improvement obtained from the addition of the GFRP. The walls were then subjected to extreme-level earthquake records to examine the ultimate failure modes and the effects of the various GFRP configurations on the response of the walls. It was observed that all strengthened specimens performed well during the design-level shaking, and three of the four GFRP configurations also performed well during the extreme-level shaking. The tests showed that the use of vertical GFRP strips alone is able to improve the in-plane performance of URM walls. The strips were also able to control the failure modes, and prevent collapse after severe damage, improving significantly the life safety performance of URM walls.