A Numerical Study of Strengthening the External RC Frame Connection with Steel Plates and RC Blocks

Abstract

A theoretical examination of methods for strengthening the outside joints of an RC frame. Considering the variety of extensive methods available for retrofitting structures, selecting the most suitable technique or substance is frequently challenging. This research was performed to assess the efficiency of external steel plates and RC blocks to strengthen the connection. ABAQUS program analyzes the effects of several factors on the joints, such as steel plate thickness, different positions of steel stiffeners and RC blocks, the concrete’s compressive strength for blocks, as well as the volume of rebar in blocks. The findings were assessed and contrasted with previous studies outcomes. The analysis highlighted that an optimum steel plate thickness is 6 millimeters. Also, steel plate has been associated with greater failure loads. Furthermore, employing stiffeners in the tension zone increases resistance by 33%, while applying them in both the tension and compression zones increases strength by 48.7%. On the other hand, utilizing RC blocks enhances resistance by 74%. Furthermore, using blocks on both sides increases the failure load and reversal moment resistance. Besides, using a greater number of smaller-diameter bars for the same area of steel in an RC block increases strength by 58%.