The effectiveness of Polymer reinforced Concrete Masonry (CMU) Walls Essay

The effectiveness of Polymer reinforced Concrete Masonry (CMU) Walls as Compared to unreinforced CMU Walls - Essay Example Using of FRP composites have been viewed as a suitable and cost-effective way for strengthening URM. Seismic design in the USA is nearly completely grounded on the consideration that the structural system gives a flexible failure mode. Masonry walls strengthened by FRP actually have fragile failure modes as a result of the nature of the strengthening system itself. The idea explored in our research paper is the introduction of flexibility using some kind of hybrid strengthening system. We based our investigation on the experiments held by J.J. Myers and P. Carney (cited in Tumialan, 2005). The research study investigated the practicability of developing continuity between the FRP and the surrounding reinforced concrete frame system. In the paper, we evaluated strengthened URM wall's functioning using static tests as tools for our investigation. The authors whose works we used for the examination utilized 2 strengthening methods including the application of glass FRP (GFRP) laminates to the wall's surface and the installation of near surface mounted (NSM) GFRP rods. In both methods, the strengthening material was anchored to boundary members above and below the wall on some of the specimens in the research program. A shear retrofit, the effects of bond pattern, and the effects of FRP laminate strip width were also investigated in our paper. The development of continuity between the FRP materials and the surrounding framing system is important to improving the blast resistance of URM infill walls. Keywords: FRP strengthening; blast resistance; masonry wall retrofits; masonry wall connections. 1. INTRODUCTION 1.1. BACKGROUND Recent events in the world have attracted attention to the vulnerability and sustainability of buildings and infrastructure to acts of terrorism. Our infrastructure is vital to this nation's economy and way of life. Any damage to it would and has had drastic effects on our culture. Attacks may cause a variety of results ranging from minor building damage to complete structural failure and considerable loss of life. Some examples within the United States include the bombing of the Murrah Federal Building in Oklahoma City (1995) and the bombing and attacks on the World Trade Center in New York City (1993, 2001). Abroad, numerous attacks have been directed toward embassies, and suicide car bombers have been used to targetpopulated areas. In the cases where complete structural failure is not an issue, the dangers of flying debris have resulted in loss of life or injury to numerous civilians. Of particular concern are unreinforced masonry (URM) infill walls. Structural sys tems composed of a reinforced concrete (RC) framing system with URM infill walls makes up a significant portion of the building inventory in the United States and around the world. Since there is no reinforcement within these walls, they have little resistance to out-of-plane loads such as a blast load. As a result, an effort has been undertaken to examine retrofit methods that are feasible to enhance their out-of-plane resistance. One method of strengthening URM walls is the application of fiber reinforced polymers (FRP) to the surface of the wall to improve their performance. Today, FRP is considered an emerging technology. Its use began becoming