Review on Push over Analysis of RCC Building with Soft Stories at Different Levels

Abstract

The increase in population, parking spaces is a major problem for the apartments of the cities. Hence fresh trend is making use of the open ground storey for parking. Also, for office, shop spaces, or conference hall etc., soft story at different levels of structure is construction. In the beyond (past) earthquake has shown that the buildings with simple (unsophisticated) and uniform configurations are subjected to less damage. The regularity and continuity of stiffness in the horizontal planes as well as in vertical direction is very important from earthquake safety point of view. A building with discontinuity is subjected to concentrated of forces and deformations at dot of the discontinuity which may leads to the failure of members at the junction and collapse of building. Open first storey is a typical feature in the modern multi-storey constructions in metro city India. Such as the features highly unacceptable of the buildings built in seismically active areas; as a been verified of numerous experiences the strong shaking during the past earthquakes. It is the thought of multi-storey buildings with soft ground floor are inherently vulnerable to breakdown due to earthquake load, their construction is still widespread in the developing nations like India. It is the social and functional demand to provide car parking space at ground level and for offices open stories at other level of structure away out-weighs the warning against such buildings from engineering community. The ground soft story for office space open floor is required on other levels of building. In present work we are concentrating on finding the best place for soft stories in high rise buildings.

Introduction

The construction of tall, slender buildings has increased the importance of designing for lateral loads such as wind, earthquake, and blast forces. Unlike older practices where lateral loads were checked after vertical load design, modern design emphasizes understanding structural behavior under these loads from the outset.

Seismic design focuses on ensuring structural safety during major earthquakes, while also considering serviceability and economic loss. Earthquake loads involve large inelastic deformations, differing significantly from wind or gravity loads, requiring detailed nonlinear analyses. Even well-designed buildings may experience some damage, as codes allow inelastic energy dissipation.

The 2001 Kutch earthquake highlighted India’s vulnerability, with most casualties linked to the collapse of non-engineered traditional buildings. Introducing earthquake-resistant features and enforcing seismic regulations are essential for both new and existing constructions. Buildings should be designed for adequate strength, ductility, and integrity, while post-earthquake observations inform improvements in design, material selection, and site planning. Performance-based design and zoning can help ensure buildings meet desired seismic performance levels and mitigate cascading failures in urban areas.

Literature Review Highlights

1. Pushover Analysis of Soft-Storey Buildings: Evaluates seismic performance of G+13/G+15 RCC frames using ETABS; highlights the impact of shear walls and structural layout on lateral displacement and base shear.

2. Soft-Storey Effect Mitigation: Shear walls and steel bracings significantly reduce drift and improve ground-floor stiffness in soft-storey RC buildings.

3. ETABS Applications: Widely used for static and dynamic analysis of high-rise and medium-rise buildings, including stilt/soft-story structures.

4. Nonlinear and Adaptive Pushover Methods: Nonlinear static and Displacement-Based Adaptive Pushover (DAP) methods provide more accurate assessments of seismic performance and inelastic behavior.

5. Key Observations: Placing soft stories higher can reduce hinge formation but increases displacements; proper detailing, structural reinforcement, and performance-based design are critical for earthquake-resistant buildings.

Conclusion

In the present study, non-linear response of RC frame high rise building with soft story at different level in addition ground floor using ETABS under the loading has been carried out. The objective of this study is to see the variation of load- displacement graph and check the maximum base shear and displacement of the frame with soft stories at different levels. 1) Plastic hinge formation for ground floor soft story and ground plus different level soft story have been obtained at different displacements levels. 2) In actual well-planned building without soft story building hinge formation starts with beam ends and base columns of lower stories, then propagates to upper stories and continue with yielding of interior intermediate columns in the upper stories. formation in this manner. 3) Comparison of the reveals that the patterns of plastic hinge formation for the different level soft story is quite different, as we shift soft story to higher level the intensity of hinge formation becomes lower and lower in soft story. 4) In this study our building model is very stiff so we cannot more and more hinges. We can see some hinges. But our hinges only up to LS level. 5) In case structure is not much stiff Hinges propagates up to CP or may be Above CP level. 6) Or in low stiff structure seen those changes in hinges severity. 7) When soft story at bottom level of building then hinges may be higher severity can be seen. When soft story at bottom level severity of hinges is high compare to when soft story at top level of building severity will be less compare to soft story at bottom level. 8) Also, numbers of hinges are more when soft story at lower level of structure. When we shift the soft story at upper floor of the structure number of hinges will also decrease. And it will be good for structure. 9) As we shift soft story lower level to higher level displacement of structure also it decreases. 10) At same time base shear of the structure also decrease. 11) In terms of effective damping of the structure, when soft story shift from lower level to higher level effective damping of the structure would be decrease. Means that less damage of structure when damping ratio is less. So, when soft story at lower level of structure damage will be maximum and we shift the soft story at higher level of the structure damages will be less compared to lower-level case. 12) It is advisable to provide soft story at higher levels in structure.

References

[1] IS 1893 (Part 1):2016 Criteria for Earthquake Resistant Design of Structures, Part 1, General Provisions and Buildings [2] IS 456 (2000): Plain and Reinforced Concrete [3] FEMA 356: Prestandard and Commentary for the Seismic Rehabilitation of Buildings [4] FEMA 440: Improvement of Nonlinear Static Analysis Procedures [5] ATC 40: Seismic Evaluation and Retrofit of Existing Buildings [6] ASCE 41-31: Seismic Evaluation and Retrofit of Existing Buildings [7] Pushover Analysis of Building using Soft Storey at Different Levels, Mr. Prathamesh Sonawane, Dr. M.P. Wagh, Volume 7 Issue 5 – May 2021 www.ijsart.com [8] Review on Pushover Analysis of Building Using Soft Storey at Different Level, Nilesh Bharat Vidhate, G.A. Sayyed, Volume 7 Issue 2, February 2021 www.ijsart.com [9] Comparative Study on Reducing Soft Storey Effect in RC Structures, Mostafa Mahumud, Md Faiyaz Shahriar, Akib Mohammad Sunny https://doi.org/10.2991/978-94-6463-672-7_7 [10] A Review on Seismic Analysis of RCC Building with Soft Storey at Different Level, Alhat Sneha Dnyananeshwar, D.N. Mandik, V.P. Bhasure, N.V. Khadake, IJRESM Volume 5, Issue 2, February 2022 https://www.ijresm.com | ISSN (Online): 2581-5792 [11] Design and Analysis of High-Rise Buildings using ETABS, Jenita Kuriakose, Sreya Shaji, Roshan Daniel, Jitu Sreekuman, IJERT Volume 11, Issue 02, 2023 www.ijert.org [12] Analysis of RCC Building with Multiple Soft Storey using ETABS, Omkar P. Khandagle, Prof., Jayant S. Kanase, IJRES Volume 10 Issue 6, 2022 www.ijres.org [13] Preventing Soft Storey Irregularity in RC Building by Pushover Analysis, Md. Abdul Alim, Nazrul Islam, IEB 49 (2) 13 October 2021 [14] Pushover Analysis of Reinforced Concrete Frames, Mila Svilar, Aleksandar Prokic, SERBIA 23-24 April 2019 CONFERENCE PROCEEDINGS INTERNATIONAL CONFERENCE (2019) [15] Nonlinear Static Pushover Analysis of Medium Rise and High-Rise Building, Dr, M. Keshava Murthy, Ashwini L K, Volume 6, 20 May 2019 https://doi.org/10.32628/IJSRST1196337 [16] Comparative study Nonlinear Pushover Analysis and Displacement Based adaptive Pushover Analysis Method, Int. J. Structural Engineering, Rutvik Sheth, Jayesh Prajapati, Devesh Soni, Vol. 9, No. 1, 2018

Copyright

Copyright © 2025 Shruti G. Kathi, Chirag R. Odedra, Dr. Kalpesh L. Kapadiya, Vandiit Bhatt, Purna B. Vachhani. 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.