Strengthening of Historical Stone Masonry Buildings in Oman using Textile Reinforced Mortars

Abstract

Most historical buildings and structures in Oman were built using unreinforced stone masonry. Such structures are prone to damage from seismic activity as these structures have negligible resistance to tensile stresses. This paper presents an exploration of the physical and chemical properties of local building materials and the results of experiments with a new strengthening technique using textile reinforced mortar. Limestone and Sarooj were the main building materials used historically in these buildings. Sarooj is a local Omani term for artificial pozzolana produced by calcining clays. Two mortar mixes were developed, one as the jointing mortar and the second as the matrix mortar. The second part of the study consisted of the construction of three masonry walls and two columns of 0.35 x 0.25 x 1.2 m (width x depth x height). The three walls were strengthened using externally bonded textiles using three different combinations of mortar and textile. One column specimen was kept as a control and the other was fully wrapped with carbon textile reinforced mortar. The walls were tested under out-of-plane four- point bending. All the wall specimens showed a significant improvement in strength up to three times its self-weight and reasonable deformation before failure. The column specimens were tested under axial compression. The failure load and displacement of the strengthened columns increased by seven and three times, respectively, compared to the control column.