Seismic performance of masonry walls with GFRP and geogrid bed joint reinforcement

Masonry is a highly durable material used in construction since hundreds of years ago. The durability of the overall masonry construction depends generally on the workmanship skills and how the units are built. In addition, masonry elements are relatively quick to construct and low in cost, and have a beautiful final appearance. It is now commonly accepted that Unreinforced Masonry (URM) structures are the most vulnerable during earthquakes. The poor performance of URM walls subjected to lateral loads is due to insufficient shear and flexural capacity. In this thesis, the results from tests on a total of eight squat concrete masonry unit (CMU) walls under simulated seismic load are reported. The first specimen is an URM control wall and one specimen was horizontally reinforced with steel-ladder shaped bed joint reinforcement. Three walls were horizontally reinforced with different configurations of GFRP material and the last three were reinforced with different configurations of Geogrid material. No vertical reinforcement was provided. The results showed that the seismic performance of URM walls due to cyclic in-plane loads can be enhanced by using GFRP or Geogrid materials when used as bed joint reinforcements. However, the level of enhancement varies due to the configuration and properties of material and also due to the distribution of the horizontal reinforcement (every course/every 2nd course). The significance of this experimental study is that it examines both FRPs and a new material, Geogrid, along with a new configuration/shape of bed joint reinforcement, grid shape.