Experimental Investigation of Masonry Infilled R/C Frames

Abstract

Although it is well documented that infills significantly affect the dynamic characteristics and the seismic response of the bare basic structural system, codes are reluctant to encourage consideration of infills as main structural elements, mainly due to structural uncertainties and computational complexities. Part of the uncertainties are due to the very many parameters affecting the behavior of the system, such as infill materials, reinforcing of infills, connection to the surrounding frame, geometry, relative stiffness and strength, local construction techniques etc. In the present paper three successive experimental programs, conducted at the R/C and Masonry Structures Laboratory of the Aristotle University, are described, commented and discussed. All of them refer to single-storey one-bay 1:3 scale R/C moment resisting frames. The first program consisted of 18 specimens, 2 bare and 16 unreinforced masonry (URM) infilled. The second program was an extension and a supplement of the previous one. It consisted of 20 more specimens, 6 bare and 14 URM infilled. The third program was directed towards the investigation of quick and low cost strengthening methods of R/C frames damaged by earthquakes, using several infill techniques. For this purpose 10 of the damaged specimens of the first program were repaired and strengthened.