Viable seismic strengthening solutions for RC wide beam-column joints

摘要

A large part of the existing reinforced concrete buildings, currently placed in earthquake-prone countries were originally designed only to withstand gravity loads, thus without appropriate strength and ductility capacity with respect to seismic actions. Beamcolumn joints play a key role on the seismic behavior of these buildings. Joints with flat or wide beam are rather widespread in the European residential building stock. However, contrary to joints provided with deep beams, there are a few studies dealing with the evaluation of their performance and, especially, the arrangement and effectiveness of strengthening solutions specifically applicable to this type of joints. For this reason, an experimental program has been set-up, mainly devoted to verify the effectiveness of a simple and easy to apply strengthening technique derived from the CAM technique. Until now, three identical specimens have been tested, one in the as-built condition and two after the application of a steel based strengthening solution. In the paper, a preliminary analysis of the test results is reported discussing the effectiveness of the proposed technique to improve the seismic performance of the joints under study.