Comparative Seismic Analysis of Regular & Irregular Building with Time History Method

Abstract

Over the decades, researchers have pre assumed in practice of structure design, that the structure is fixed at its base, As the structures are supported on soil but many structural designers do not consider the soil structure interaction (SSI) effects at the time of earthquake. The major goal of the current study is to ascertain how the interaction of soil and structure affects both regular and irregular structures with irregular stiffness in areas of high damage risk. In the current study, an effort is made to determine how soil structure interacts with buildings using E-TABS2016. In seismic zone IV, distinct soil conditions—hard (type-I), medium (type-II), and soft (type III)—are being compared using time history analysis.

Introduction

I. INTRODUCTION

One of the most crucial fields of structural engineering research today is soil structure interaction. In the process known as "soil structure interaction," the response of the soil is influenced by the motion of the structure and the motion of the structure is influenced by the response of the soil. By using SSI, designers can obtain the inertial force and actual soil foundation displacement caused by free field motion, which could result in a reduction in the cost of the project. Finite element analysis and computer-added technology have made it easier to tackle and observe problems like these throughout time in this field.

Structures fail as a result of earthquakes, and it usually starts at a weak point. Additionally, irregular constructions fall into the category of weak points due to discontinuity in mass (seismic weight greater than 150 percent of adjacent floor), stiffness irregularity, and geometry irregularity (lateral load resisting dimension greater than 200 percent of adjacent story).

During an earthquake, ground get accelerated & dynamic behavior get reflected on the superstructure  Vertical irregularity is the main cause of structural failure. When these structures are built in high seismic prone zones, such as zone IV or zone V, the analysis and designing portion of the construction becomes more challenging and complicated.

II. METHODOLOGY

In the current study, ETABS 2016 has been used to analyse a nine-story structure. Finite element analysis will be done with time history data input. The indicated characteristics of the created model are mentioned below

A comparison between a conventional building (model I), an irregular building without a slab on story 1 (model II), and an irregular building with a slab that is twice as thick on story 1 (model III) was done in the current study. Different soil conditions, such as soil types I, II, and III, which stand for hard, medium, and soft soil, respectively, as advised by the IS code 1893:2002 part I, were taken

into consideration. Different metrics, including tale displacement and drift index for various soil types, have been estimated and compared while maintaining a fixed support condition.

A. Time History Data

 Depth (Km)                                       46.0

 Magnitude                                         7.8

  Region                                   Iran-Pakistan-Border-Region

 Above details taken from  IMD

Station Code                                         DCE

 Station Lat.                                          28.795N

 Station Long.                                       77.118E

 Station Height (m)                             208.0

 Site Class                   CVs30 between200m/secto375m/sec

 Record Time                                        16.04.201310:49:13.829

Sampling Rate                                      200Hz

Record Duration                                 169.970Sec.

Direction                                                E-W(Epositive)

Max. Acceleration                                1.521cm/sec2

Conclusion

1) The results demonstrate that the behavior of models I and III, which represent a regular building and a building with a double depth of slab, behave nearly identically, but model II, which represents a building without a slab on story 1, exhibits the best results for soil displacement across all type earth 2) The results reveal that model I and model III, which represent regular and irregular buildings with double slab depths, behave almost identically, whereas model II, which represents a building without a slab on the first floor, exhibits a different behavior and provides the best drift index results for all types of earth soil 3) As per results, Analysis of the all type of the buildings i.e. regular and irregular building, Story Displacement increased as the stiffness of the soil decreases 4) Drift value of the buildings get increases as the stiffness of the soil decreases according to the places and conditions

References

[1] Jinu Mary Mathew, Cinitha A, Umesha P K, Nagesh R Iyer and EapenSakaria (2014), “Seismic response of RC building by considering soil structure interaction” International Journal of Structural & Civil Engineering, Res. ISSN 2319 – 6009 Vol. 3, pp 160-172 [2] Jiang Xinliang and Zhang Yanan (2013), “Influence of Structure Plane Size on Seismic Response of Soil-Structure Interaction”, World Earthquake Engineering, Vol.19 No.5.pp 345-350 [3] Cinitha.A, Umesha P. K and Nagesh R. Iyer (2015), “Soil structure interaction analysis for seismic response of an asymmetric RC building”, International Conference on Computer Modeling and Simulation., pp 1-6 [4] Shehata E. Abdel Raheem, Mohamed M. Ahmed and Tarek M. A. Alazrak (2015), “Evaluation of soil–foundation–structure interaction effects on seismic response demands of multi-story MRF buildings on raft foundations”, Advance Structural Engineering., pp 11-30 [5] IS 1893(Part 1):2002, Criteria for Earthquake Resistant Design of Structures-General provisions and Buildings, Bureau of Indian Standards, New Delhi. [6] Shreya Thusoo, Karan Modi, Rajesh Kumar, Hitesh Madahar, “Response of Buildings with Soil Structure Interaction with Varying Soil Types” , International Journal of Civil, Environmental, Structural, Construction and Architectural Engineering, Volume-09, No-4,2015. [7] Kuladeepu M N, G Narayana, B K Narendra, “ssi effect on dynamic behavior of 3Dbuilding frames with raft footing”, IJRET: International Journal of Research in Engineering and Technology eISSN:2319-1163 |pISSN:2321-7308. [8] Renu Raghuveeran, Hashifa Hassan P, “Seismic Soil Structure Interaction Effects on RC Bare Frames Resting on Pile-Grid Foundation”, International Journal of Scientific and Research Publications, Volume5, Issue10, October 2015 1ISSN2250-3153. [9] Mr. Rahul Sawantand. M.N. Bajad (2016), “Effect of Soil-Structure Interaction on High Rise RC Building”. IOSR Journal of Mechanical and Civil Engineering (IOSRJMCE), Volume 13, Issue1,pp85-91 [10] Nitish Kumar. S,Praveen J. V. “Study of Soil Structure Interaction Effect on Multi-Story RCFrame Structures Resting Over Raft Foundation under Earthquake Caused Agitation”, InternationalJournal of Engineering Research & Technology (IJERT), ISSN: 2278-0181, Vol. 5 Issue 06, June-2016.

Copyright

Copyright © 2022 Piyush Mishra, Prince Yadav. 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.