A METHOD TO ENHANCE SEISMIC PERFORMANCES OF UNREINFORCED MASONRY STRUCTURES DERIVED FROM LATERAL FORCE RESISTING MECHANISMS OF MASONRY INFILLED FRAMES

This paper mainly discusses seismic performances of specially designed unreinforced masonry (URM) structures. Firstly, lateral force resisting mechanisms of masonry in filled frames were introduced through test results of concrete block in filled reinforced concrete frames with and without a door opening. Based on major findings from the tests, a method to enhance seismic performances of URM structures using interlocking masonry units was proposed. Two new URM walls consisting of brittle and ductile interlocking masonry units were tested and their performances were compared with that of a conventional one. Seismic performances of URM walls could be effectively improved by interlocking masonry units.