TRM-to-Masonry Bond under Elevated Temperatures: Lightweight versus Normalweight Matrices

Abstract

In the last decade, Textile Reinforced Mortar (TRM) systems have increasingly been gaining ground as a means of strengthening damaged or seismically deficient masonry structures, in addition to counterpart reinforced concrete ones. The existing experimental data on the behavior of TRM materials (used as externally bonded reinforcement on masonry – or concrete – substrates) under elevated temperatures still remains scarce. This work aims at enriching the existing data on the influence of elevated temperatures on the TRM-to-masonry bond conditions. The applied TRM systems consisted of a cementitious mortar with normalweight (limestone) or lightweight (pumice) aggregates. Shear bond tests on single-lap/single-prism specimens were conducted after the exposure of the specimens at different temperature levels. All specimens (masonry prisms with ridge-faced fired clay bricks) were unilaterally furnished with a dry AR glass TRM comprising a single textile layer; TRM bond length was kept constant for all specimens tested. Tests were carried out by varying both the type of matrix employed (normalweight vs. lightweight) and the exposing temperature. The experimental results provide an insight on the effect of mortar type (comprising either normalweight or lightweight sand) on the TRM-to-masonry bond capacity as a function of the exposure temperature.