Anchorage systems for masonry walls strengthened with FRP composite laminates

This study examined the anchorage of FRP systems in strengthening masonry walls against out-of-plane lateral loads. The anchorage methods utilized (i) improved bond; (ii) a fiber anchor bolt system; and (iii) an embedded bar system. Tests were carried out on eight walls of half-brick thickness and seven walls of full-brick thickness, strengthened with two different types of glass and one carbon FRP systems. Each wall was placed in a horizontal plane and simply supported along four sides without edge restraint, and then subjected to a uniformly distributed pressure applied using an air bag over a square area at its centre. Test results indicated that specimens without any anchorage measures showed premature failure by FRP debonding, while those provided with an anchorage system, failed by brick crushing or by punching shear at a much higher load. An analytical model is also presented to predict the failure load of FRP reinforced masonry walls failing in flexural compression or punching shear, and was found to predict test results well.