Assessment of the effectiveness of grout injection on the consolidation of 3-leaf stone masonry walls through the use of NDT and DT

In this paper it is presented the experimental campaign on multi-leaf stone masonry panels in original and consolidated conditions that was performed at the Laboratory of Building Materials of the Department of Civil, Environmental and Architectural Engineering (University of Padova). The experimental research includes a series of monotonic and cyclic simple-compression tests on three-leaf stone masonry panels in scale 1:1 and 2:3, in original and consolidated conditions using grout injection, and a single-leaf stone masonry wall in scale 1:1. These tests were complemented by Non-Destructive Tests (NDT - direct and indirect sonic tests, sonic tomography) performed on the walls before and after the strengthening and by the mechanical, physical and chemical characterization of the applied materials (stone, mortar and grout) and of composite elements of stone fragments and grout, in both scales 1:1 and 2:3, simulating the masonry internal core panels. Both NDT and DT allowed assessing the effectiveness of the grout injection as a reinforcement technique and to expand and deepen the knowledge on its influence on the behaviour of the studied type of masonry. Furthermore, it was established a relation between the velocity values obtained using NDT and the mechanical parameters obtained with the DT.