Comparison of Seismic Performance of RC Frames Strengthened with Four Different Techniques

Abstract

The purpose of this experimental study is to compare the strengthening techniques that are applied to non ductile low rise RC frames under seismic loads. In this study, 1/3 scale, one-bay, one-storey, nonductile RC frames with masonry infill walls were strengthened using four different techniques and are tested experimentally under reversed cyclic lateral loading. The four frames were constructed with masonry infill walls and three were strengthened with a mesh reinforced mortar layer, CFRP and steel strips wrapping, respectively. The remaining one without any extra strengthening was tested as a reference. A final specimen of the experimental program was strengthened with RC infill instead of masonry infill. Strength, stiffness, storey drift, ductility and failure modes of the specimens were evaluated and compared experimentally. Each strengthening technique proved to have different types of effectiveness on the lateral strength and stiffness of non ductile RC frames. Different strengthening techniques changed the ultimate lateral strengths and stiffnesses within the ranges of 53% to 381% and 82% to 601%, respectively.