The paper presents a seismic safety assessment of unreinforced masonry(URM)building using two approaches.The first approach uses the‘Pier Analysis’method,based on the concept of equivalent lateral stiffness,where in...The paper presents a seismic safety assessment of unreinforced masonry(URM)building using two approaches.The first approach uses the‘Pier Analysis’method,based on the concept of equivalent lateral stiffness,where in-plane and out-of-plane actions are considered independently.The second approach is developed with the program SAP2000,where the linear response is evaluated using continuum‘finite element modelling’(FEM).Both methods are compared to evaluate the safety of wall piers and the differences in the outcomes under combined gravitational and lateral seismic forces.The analysis results showed that few wall elements are unsafe in in-plane and out-of-plane tension.It is also observed that the pier analysis method is conservative compared to FEM,but can be used as a simplified and quick tool in design offices for safety assessment,with reasonable accuracy.To safeguard the URM wall piers under lateral loads,a retrofitting technique is adopted by providing vertical and horizontal belts called splints and bandages,respectively,using welded wire mesh(WWM)reinforcement.The study using the‘Pier Analysis’shows that the lateral load capacity of unsafe URM piers can be enhanced up to 3.67 times and made safe using the applied retrofitting technique.Further,the retrofitting design methodology and recommendations for application procedures to on-site URM buildings are discussed in detail.展开更多
基金project of Indian Institute of Technology Roorkee(No.EQD-6031/2019-20)for conducting this research work.The support received from the grant authority is gratefully acknowledged.
文摘The paper presents a seismic safety assessment of unreinforced masonry(URM)building using two approaches.The first approach uses the‘Pier Analysis’method,based on the concept of equivalent lateral stiffness,where in-plane and out-of-plane actions are considered independently.The second approach is developed with the program SAP2000,where the linear response is evaluated using continuum‘finite element modelling’(FEM).Both methods are compared to evaluate the safety of wall piers and the differences in the outcomes under combined gravitational and lateral seismic forces.The analysis results showed that few wall elements are unsafe in in-plane and out-of-plane tension.It is also observed that the pier analysis method is conservative compared to FEM,but can be used as a simplified and quick tool in design offices for safety assessment,with reasonable accuracy.To safeguard the URM wall piers under lateral loads,a retrofitting technique is adopted by providing vertical and horizontal belts called splints and bandages,respectively,using welded wire mesh(WWM)reinforcement.The study using the‘Pier Analysis’shows that the lateral load capacity of unsafe URM piers can be enhanced up to 3.67 times and made safe using the applied retrofitting technique.Further,the retrofitting design methodology and recommendations for application procedures to on-site URM buildings are discussed in detail.