Measurement of Grout Injection Efficacy for Stone Masonry Walls

Abstract

For nearly a century, cementitious materials have regularly been injected into masonry structures in attempts to rehabilitate and retrofit them. Typical subjects for this treatment are multiple-leaf, stone walls characterized by poor bonding between external and internal leaves, presence of voids, lack of adhesion between the mortar and the stones, poor cohesion of mortar in the joints and in the rubble infill, possible presence of dry walls in the load bearing system. Unfortunately, most of this has been done without the ability to measure the success of the intervention. Though important progress has been made for establishing potential grout flow through extremely fine material, little is known on the efficacy of treatment in heterogeneous stone walls. The experimental work presented in this paper provides a contribution in establishing a laboratory correlation between visual verification and ultimate resistance, through the assessment of a material groutability and the determination of compressive strength.