Strengthening of RC frames by using high strength diagonal precast panels

Abstract

The published literature reports several studies examining methods for strengthening of infilled walls. One proposed approach is the strengthening of infilled brick walls by employing high -strength precast concrete panels, which permits. This approach permits manufacture of precast panels with a variety of geometrical shapes. Strengthening is subsequently achieved by attaching such panels over the entire surface of the plastered brick infilled walls. However, experiments have shown that this technique can result in the formation of bandwidth diagonal cracks on brick-infilled walls. Therefore, instead of covering the whole surface, the orientation of the panels can be adjusted to observe improvement in the lateral stiffness. This study proposes a practical, easily applicable and economical approach for strengthening reinforced concrete structures against earthquake, without the need to disturb residents of a building. Laboratory tests were carried out on infill walled reinforced concrete frames (of 1/3 scale) strengthened with various panel configurations. Results of the proposed strengthening methods are reported following examination of the tests. All experimental studies were performed via reversed-cyclic horizontal loading to simulate earthquake conditions. According to results of the experiments, the lateral load carrying capacity, stiffness at the maximum load and energy dissipation capacity for the best performing strengthened specimen increased by around 3.74 fold, 12.34 fold and 4.29 fold, respectively.