Linear Dynamic Analysis and Seismic Response Evaluation of High Rise Structures with Shear Walls Base Isolation and Composite Framing Systems

Abstract

An earthquake is a naturally occurring movement of the ground that results in a disaster and damages structures. Waves are produced by seismic activity in the earth\'s crust. Through the foundation, these waves reach the structures. Therefore, inertia force is triggered in the structure as a result of the seismic movements, which damages the entire building or just a portion of it. The most recent advancement in seismic-resistant architecture is base isolation, which lessens the impact of ground movement even though it may not completely control it. By extending the time that a structure vibrates, base isolation helps to reduce earthquake forces. Additionally, because of base isolation, the structural response accelerations are lower than the ground acceleration. In addition to the foundation isolation, earthquake-resistant buildings also incorporate shear walls. In addition to slabs, beams, and columns, reinforced concrete (RC) buildings frequently have shear walls, which are vertical plate-like RC walls. These walls are often continuous throughout the height of the building, beginning at the foundation. It lessens the impact of earthquakes and their aftereffects. However, several nations have long recognized the superior earthquake-resistant performance of composite beams and columns. Because of its lower seismic weight, the steel and concrete composite structure is growing in popularity. The linear dynamic analysis of an RCC structure with an energy dissipation device in zone IV is examined in this paper, along with a comparison to a composite structure. Because linear dynamic analysis calculates the structure\'s response to ground motion in the time domain, all phase information is preserved. Three distinct models were subjected to response spectrum analysis using CSI ETABS v21; multiple values for each model were determined from the structure. The building is situated in seismic zone IV. The response of the building is analyzed using three models. For a G+25 RC frame structure with a shear wall, the outcomes of frequency, time period, displacement, drift, story overturning moment, and story stiffness are compared.

Introduction

Tall buildings in earthquake-prone areas are vulnerable to seismic forces. This study focuses on evaluating three structural systems for a 25-storey building under seismic conditions:

1. RCC with shear walls

2. RCC with base isolation

3. Composite structures

Base Isolation

Base isolation allows buildings to move independently from ground motion, reducing seismic forces, inter-story drift, and structural damage. It lowers base shear, minimizes reinforcement requirements, and is essential for critical infrastructure in high-risk zones.

Composite Structures

Composite structures (steel + concrete) offer improved seismic resistance, design flexibility, and faster construction. They provide high strength-to-weight ratio, ductility, and ease of repair, making them ideal for earthquake-prone regions and modern architectural designs.

Research Gap

While prior studies examined base-isolated or composite systems separately, comparative analysis of RCC with shear walls, base-isolated RCC, and composite structures under identical seismic loading is limited.

Objectives

• Analyze and compare seismic parameters (e.g., base shear, story drift, deflection, time period) for all three structural systems.

• Identify the most efficient structural system for high-rise buildings in Seismic Zone IV, using ETABS v21 and IS 1893:2016 standards.

Methodology: Linear Dynamic Analysis

The study uses linear dynamic analysis (response spectrum method), which models the building as a Multi-Degree of Freedom (MDOF) system with linear elastic behavior. This approach:

• Accounts for higher mode effects

• Is more accurate than static methods for tall or irregular structures

• Involves modal decomposition to simplify analysis

Conclusion

A. Time Period • The modal time period is 4.93 seconds in model 2, 4.08 seconds in model 1, which is a G +25 RC frame construction with a shear wall at the core, and 4.356 seconds in model 3. • Model 2\'s modal time period is 13.17% longer than Model 3\'s and 20.83% longer than Model 1\'s. • The ductility of the structure greatly rises due to base isolation in model 2, which causes the time period to grow and the frequency to drop. B. Story displacement • Model 2 has the largest story displacement (85.786 mm), while Model 1 has the smallest (58.956 mm). Model 3\'s story displacement is 64.12 mm. • Model 2\'s story displacement is 33.789% greater than Model 3\'s and 45.81% greater than Model 1\'s. • Displacement falls with increasing rigidity and vice versa. C. Maximum Story Overturning Moment • Model 1 has the highest story overturning moment (130235.69 KN-M), while Model 2 has the lowest (116373.34 KN-M). Model 3 has the lowest story overturning moment (124470.64 KN-M). • Model 1\'s maximum story overturning moment is 11.91% higher than Model 2\'s and 4.63% higher than Model 3\'s. D. Story Drift • Model 1 has the least amount of story drift, whereas Model 2 has the most. Following analysis and all design checks in accordance with IS: 1893 (2016), story drift meets design requirements and its value is less than 0.004 times the story height. • The drift ratio falls as the structure\'s stiffness rises and vice versa. E. Base Shear • Model 1 has the highest base shear, 1514.36 KN, while Model 2 has the lowest, 853.66 KN. Model 3\'s base shear is 1366.87 KN. • Model 2\'s base shear is reduced by 43.62% compared to Model 1 and 37.54% compared to Model 3. • Base shear rises in tandem with a structure\'s bulk. F. Story Stiffness • Model 1 has the highest story stiffness, measuring 120627.1 KN/M, while Model 2 has the lowest; measuring 91676.5 KN/M. Model 3\'s tale stiffness is 102533.5 KN/M. • Model 2\'s story stiffness is 11.57% lower than Model 1\'s and 11.84% lower than Model 3\'s. • The structure\'s stiffness decreases as its ductility increases, and vice versa.

References

[1] Jagadale S, Shiyekar M.R. and Ghugal Y.M. July-2019 “Comparative Study of Steel, RCC and Composite Frame Building”. ISSN: 2395-0072, Volume 6, Issue 7, IRJET. [2] Rana M 2019 “comparative study in steel structure on better resistance against lateral load” ISSN: 2764-1322X, Volume 5, Issue 5, IJARIIT [3] Patel K, Thakkar S. 2019 “Analysis of CFT (Concrete Filled Steel Tube), Rcc and Steel Building Subjected to Lateral Loading”, Elsevier. [4] Savadi S. and Hosur V.2019 “Comparative Study of RCC, Steel and Composite Structures for Industrial Building”. ISSN: 2395- 4396, VOLUME 5, issue 4, IJARIIE. [5] Bhanu P.M. (2021) “Comparative Study of Composite RCC and Steel Structure” International Journal of Advanced Engineering Research and Studies III (I): 88–93. [6] Nassani D.E. and Mustafa W.A. (2021). “Seismic Base isolation in reinforced Concrete structures.” international magazine of studies studies in technology, Engineering and era, 2(2), 1-thirteen. [7] IS: 456-2000 (Indian Standard Plain Reinforced Concrete Code of Practice)– Fourth Revision. [8] IS: 1893-2002 (part-1), Criteria for earthquake resistant design of structures, fifth revision, Bureau of Indian Standards, New Delhi, India. [9] Bureau of Indian Standards: IS:875-1987, (part 1), Dead Loads on Buildings and Structures, New Delhi, India. [10] IS: 875-1987 (part-2) for Live Loads or Imposed Loads, code practice of Design loads (other than earthquake) for buildings and structures. [11] Duggal SK. Earthquake Resistant Design Structures. Oxford university press YMCA library building, New Delhi, 2010. [12] IBC (2000). “International constructing Code”, worldwide Code Council, Inc., Virginia, U.S.A. [13] IS: 13920 (2016). “Ductile layout and detailing of reinforced concrete systems subjected to seismic forces-code of practice.” Bureau of Indian requirements, New Delhi, India. [14] IS: 1893 (element I, 2002). “Standards for earthquake resistant layout of systems, element 1: general provisions and buildings [CED 39: Earthquake Engineering]”, Bureau of Indian standards, New Delhi, India. [15] IS: 1893 (part I, 2016). “Standards for earthquake resistant design of systems, component 1: trendy provisions and homes [CED 39: Earthquake Engineering]”, Bureau of Indian standards, New Delhi, India.

Copyright

Copyright © 2025 Vikram Kesharwani, Lavina Talawale. 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.