SEISMIC ANALYSIS OF MASONRY BUILDINGS

Abstract

Occurrences of earthquakes in India resulting losses, mainly human lives, have highlighted the structural insufficiency of buildings to bear seismic loads. However, a lot of construction techniques have been introduced, masonry has got its significance in construction industry. Masonry buildings of stone and bricks are more durable, fire resistance and heat resistant. Because of effortless accessibility of masonry materials and due to construction cost reasons, this method of construction is engaged in urban, rural and mountainous areas. Masonry structure fails mainly due to the action of lateral loading cases like earthquakes load. In the past earthquakes, it was observed that masonry structures were damaged, partially and fully. Failure of masonry is still contributing a major part of threat to the life safety. Past world–wide earthquake experience shows that the un-reinforced masonry structure is more vulnerable than reinforced structure. Unreinforced masonry buildings are usually characterized by sudden and dramatic collapse. The work is primarily dealing with the seismic analysis of the structure. The building modeled in FEM-based software SAP2000 for detailed structural analysis together with all material properties, loads and its combination. A comparative study on non-linear behavior of masonry frame structures when subjected to earthquake excitation under different lateral loading pattern. Equivalent Frame Model (EFM) is being used for modeling the non-linear behavior of masonry by providing flexural and shear hinges in the model. The flexural hinges are defined based on equations derived through experimental study on unreinforced masonry (URM) walls. The shear hinges are defined using equations obtained through regression analysis of bi-linearized pushover curves of the URM walls. Analysis is done in SAP2000 software and useful conclusions on strength are drawn.