Seismic performance of confined versus unreinforced masonry buildings on hilly slopes using linear static and dynamic analysis approaches

Abstract

The stability of non-compliant masonry buildings often depends on adequate reinforcement measures, expecting detailed structural assessment and reinforcement using proper techniques. Structural assessment of masonry buildings with poor building practices is a key issue in hilly regions in general that requires prompt attention. This paper addresses the seismic assessment of code-deficient unreinforced masonry (URM) buildings and their strengthened counterparts using a confined masonry (CM) structure, located in a hilly region in seismic zone IV of India. By estimating stress parameters, the seismic behavior of the buildings has been evaluated with the help of SAP2000 software and identified corresponding deficient elements of the structures. Intent of the present research is to explore the scope of improvement in structural safety of URM, taking CM as a better alternative focused to hilly areas. For this analysis linear static and dynamic methods have been used being a usual method for the analysis of seismic effects. Analysis reveals that tensile and shear stresses exceed the permissible limits (IS code- 1905:1989) at all floors in case of URM construction for height 9 m (G+ 3) which is within limit as all floors for a building of 15 m (G+ 5) in case of CM construction. In this case stresses (tensile and shear) exceed on ground floor only which needs to safe guard as the time of design. A overall, CM structure is found a better alternative for constructing moderate rise building in hilly areas.