The masonry walls should have sufficient in-plane strength and stiffness to withstand the seismic loads during strong ground shakings. Different retrofitting techniques are proposed for improving in-plane behavior of the Unreinforced Masonry (URM) walls. This study focuses on experimental evaluation and numerical simulation of a simple practical retrofitting technique employing Fiber Reinforced Concrete (FRC) surface layer. The simple FRC mix has conventional available fiber, low fiber content, ordinary mix design and applicable construction procedure. Effect of FRC mix including fiber type and fiber content and surface layer thickness on in-plane behavior of masonry panels made up of conventional solid clay bricks are evaluated through experimental study in accordance with ASTM E-519 diagonal tension strength of masonry panels. In addition, numerical simulation model of this retrofitting technique in ABAQUS software is proposed and validated with test results of bare and retrofitted panels.

Concentrically braced frames provide ductility and imparted seismic energy dissipation through yielding of tension braces and buckling of compression braces. In braced frames with chevron configuration, difference of actions in tension and buckled brace results in considerable unbalanced force at brace-beam intersection, which is addressed in modern seismic design provisions. In this paper, effect of flexural capacity of beam to carry this unbalanced force and consequently seismic behavior of braced frame is investigated by finite element analysis. Two-story and four-story chevron braced frames were modeled in ABAQUS software and studied by means of nonlinear cyclic pushover and nonlinear response history analysis methods. Results showed that inadequate flexural strength of the beams reduce lateral stiffness and strength of braced frame significantly as lateral drift increases; therefore, concentration of lateral deformation in one story may cause formation of soft and weak story. Furthermore, seismic behavior of chevron braced frame and two-story X braced frames were compared.