Seismic Analysis of Irregular Multistorey Building

Abstract

The seismic analysis of buildings is crucial for ensuring structural safety and resilience against earthquake forces. Irregularities in building configurations pose unique challenges, influencing the distribution of seismic forces throughout the structure. This study focuses on the seismic analysis of a G+12 building characterized by irregularities in plan and elevation using STAAD.Pro software. Here we have taken four models consisting of bare bay frame , bay frame with shear wall on one corner, , bay frame with shear wall on two opposite corners, , bay frame with shear wall on all corners for the further analysis. This research contributes to enhancing understanding and design practices for irregular high-rise buildings, emphasizing the importance of advanced analytical tools in seismic engineering. From this analysis we can conclude that within all four models ,building having shear wall on all four sides shows minimal deflection attributed to its maximum stiffness characteristics, hence considered most stable.

Introduction

I. INTRODUCTION

The structural integrity of high-rise buildings during seismic events is critical for ensuring public safety and minimizing economic losses. Irregularities in building geometry and structural configuration can significantly influence seismic vulnerability and require careful analysis and design considerations. Findings from the analysis of irregular buildings contribute to the development and refinement of building codes and standards. This ensures that structures are designed and constructed to withstand seismic forces effectively, enhancing public safety.

Knowledge of how irregular buildings respond to seismic forces contributes to disaster preparedness efforts. It allows authorities to develop emergency response plans and evacuation strategies tailored to specific building types, ultimately saving lives during earthquakes.

II. METHODOLOGY

 This study employs a linear static approach using STAAD.Pro software to model and simulate the structural behavior of the G+12 irregular building under seismic loading. The methodology includes:

• Building geometry and structural details
• Material properties and seismic design parameters
• Application of ground motion records as per seismic hazard analysis
• Analysis of seismic response including modal analysis, dynamic time history analysis, and response spectrum analysis.

The four models are as follows:

• MODEL 1: Bay frame with no shear wall. 
• MODEL 2: Bay frame with shear wall placed at one corner.
• MODEL3: Bay frame with shear wall placed at two corners.
• MODEL4: Bay frame with shear wall placed at all corners.

VI. DISCUSSION

The findings are interpreted to assess the building's seismic vulnerability and performance under various earthquake scenarios. Key factors influencing the structural response, such as irregularities in plan and elevation, are analyzed. Comparison with relevant design codes and standards is also discussed.

Conclusion

In conclusion, the seismic analysis using STAAD.Pro software provides valuable insights into the behavior of the G+12 irregular building under seismic loading. Recommendations for structural enhancements and future research directions are outlined to improve seismic resilience in high-rise constructions. 1) The base shear is maximum in model with shear wall at two opposite corners in both static and response spectrum analysis, and the minimum value in model in both cases in x- direction and z-direction. 2) The model with shear wall at two opposite corners seems to give a large deflection due to its concentrated mass at a corner (mass irregularity) present in the structure. Whereas the model having shear wall on all corners produces least deflection in all type of structure considering maximum stiffness. Hence we can conclude that of all the types , building model having shear wall on all corners exhibits overall stable results.

References

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Copyright

Copyright © 2024 Riju Kumari, Gautam Kumar. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.