International Journal of Earth Sciences and Engineering

H. K. Chinmayi ¹, B. R. Jayalekshmi ²

Affiliations
1 Department of Civil Engineering, Manipal Institute of Technology, Manipal-576104, IN
2 Department of Civil Engineering, National Institute of Technology Karnataka, Surathkal-575025, IN

Abstract

In the present study, a three-dimensional dynamic soil-structure interaction analysis of symmetric buildings in time domain is performed using IS spectrum ground motion record corresponding to zone III to evaluate the dynamic response of structure-foundation-soil system. Three types of shear wall buildings of aspect ratio 1, 1.5, 2, 3 and 4 categorized based on the shear wall locations were considered in conjunction with four types of soil of shear wave velocities ranging from 150 m/s to 1200 m/s, symbolizing soil classes B, C, D and E of FEMA-356:2000. Integrated structure-foundation-soil systems were analyzed using commercial finite element software LSDYNA, based on direct method of soil-structure interaction (SSI) assuming linear elastic behavior. The study shows considerable variation in dynamic characteristics and structural seismic response of the structure due to the incorporation of the effect of flexibility of soil and position of shear walls. Tall buildings with shear walls placed at the exterior corners experience the least base shear.

Keywords

Soil-Structure Interaction, Soil Flexibility, Shear Wall, Base Shear, Time History.

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S. P. Malini ¹, H. K. Chinmayi ¹

Affiliations
1 Department of Civil Engineering, Nagarjuna College of Engineering and Technology, Bangalore-562164, IN

Abstract

Rise in urbanization and due to scarcity in space available on the horizontal ground, there is a need for vertical expansion of cities. For which the high rise constructions are needed. Behaviour of the tall buildings subjected to wind loads along with vertical gravity loads is very much essential due to their vulnerability. This paper tries to explore the shape effect of buildings against the wind load using design software E-TABS. Different wind load patterns are ventured on various shapes of building viz. Square, Circular and Octagonal on direction basis to determine the response of buildings. Buildings of heights G+20 and G+40 are subjected to varying wind speeds of 33 m/s, 44 m/s and 50 m/s to determine the response of the building with varying shapes. The study focuses on maximum bending moment in columns, maximum roof displacement and storey drift. Shapes play an important role in resisting the wind loads and circular shaped building is found to perform the best.

Keywords

Tall Building, Wind Load, E-TABS, Roof Displacement, Inter Storey Drift, Bending Moment.

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