DYNAMIC ANALYSIS OF MULTISTOREYED BUILDING SUBJECTED TO BLAST LOAD

Abstract

Terrorists have targeted iconic and public buildings in recent years. Terrorists are developing high-intensity bombs as technology advances. Bomb blasts and threats are a growing problem all over the world. The protection of human life against such attacks includes the prediction, avoidance, and modification of such events. In recent years, the design and analysis of such impulsive loads applied to structures have been thoroughly investigated to determine the performance of structural elements subjected to the sudden type of loading. Because blast loads are highly unpredictable and dynamic in nature, it is extremely unlikely that a fully blast resistant structure can be designed. As a result, it is critical to comprehend the effect of blast on the structure and the behaviour of structural elements as a result of the load. Depending on the location of the blast, the structure suffers a partial or complete collapse of structural members, resulting in the loss of structural integrity. In this study, static and dynamic analyses are performed on Extended Three Dimensional Analysis of Building System (ETABS) 2019 to analyse the response of a G+5 storey building subjected to blast effect due to the blasting of 100kg TNT explosive at various locations. The blast parameters, such as peak reflected overpressure and positive phase duration, are calculated using the codes IS 4991-1968 and UFC 3-340-02, and pressure time history analysis is performed. Various structural systems, such as shear walls and steel bracings, are used to make the building more resistant to blast loads. Structural modifications such as increasing column size and changing plan configuration are carried out to determine their impact on the structure's blast response. The two elements taken into consideration when assessing the building's safety are the storey displacement and the storey drift. The building's behaviour under a blast load is expressed in terms of safe standoff distance. For the study, two different blasting locations—namely, blasting at the front face and blasting at the corner side— are taken into consideration. A bare frame model's blast response and safe standoff distance are compared to other models with structural modifications. This study's major goal is to shed light on the idea of blast-resistant buildings and to determine how a structure will react to blast loads using ETABS software, with special emphasis placed on various standoff distances from the blast.