Performance of hollow concrete block masonry walls retrofitted with steel-fiber and microsilica admixed plaster

The weakness of existing unreinforced masonry (URM) wall buildings in resisting lateral loads is a matter of concern, especially in locations exposed to seismic hazards. In order to address this shortcoming, considerable research effort has been dedicated in the last few years on the strengthening techniques of existing URM structures. This paper presents the test results of four hollow concrete block walls, one as control, one using high steel-fiber reinforced mortar admixed with microsilica (SFR-MS) mortar in joints and the other two walls plastered with 10 mm thick SFR-MS mortar on one and both sides of the wall, respectively. The shear capacity, stiffness, cracking patterns and failure modes of the walls were investigated. In addition, a nonlinear finite element simulation of the walls in an ABAQUS environment is presented and results compared with those obtained from the experimental investigations conducted. Modified analytical equations for predicting the shear capacity of masonry walls with plaster is proposed and results compared with the experimental and finite element simulation results of the investigated walls.