Procedure for Determining Seismic Vulnerability of Building Structures

A rationalization for ranking reinforced concrete frame buildings with masonry infill walls with regard to seismic vulnerability is presented. The method essentially requires only the dimensions of the structure as input, and is expressed in terms of where its attributes are located in a two-dimensional plot of masonry wall and column percentages. It is shown that increasing drift at the ground story (which is a reasonable expression of increasing vulnerability) is attained by decreasing either attribute. It is shown that a more robust estimate of the contribution of the filler wall to frame stiffness should be based on the compression-tension strength of its mortar rather than the elastic modulus, either of the masonry or of the mortar.