Detailed vulnerability assessment and seismic upgradation of non-engineered masonry building

ABSTRACT Structural safety of code deficient non-engineered buildings relies on adequate strengthening measures, which demands detailed structural assessment and strengthening using the appropriate technique. Structural appraisal of non-engineered buildings with poor construction practices is a key issue, which requires immediate attention. This paper deals with seismic evaluation and rehabilitation of a seismically deficient unreinforced masonry (URM) building. A Detailed Vulnerability Assessment (DVA) was carried out, which included visual inspection; on-site and laboratory tests on building elements, linear static and dynamic analysis to identify structurally deficient elements through evaluation of stress parameters. The existing building was found to be in distressed condition with regards to material and structural requirements as speculated from DVA, further to which adequate strengthening techniques for seismic upgradation of the building were proposed. The main strengthening measures included galvanized iron welded wire mesh (GI WWM) and shotcrete for walls and columns, along with micro-piles-cum-raft for foundation. The building was re-analyzed after strengthening, which showed improved structural parameters complying with the codal limits. It is expected that the proposed seismic evaluation and rehabilitation methodology will be helpful to practising engineers for improving the seismic resilience of URM buildings.