A Case Study: Effect of Soil-Flexibility on the Seismic Response of Reinforced Concrete Intermediate-Rise Regular Buildings in Halabja City

Author: Rabar Faraj1
1Building and Construction Engineering Department, Halabja University, Halabja, Iraq

Abstract:  On November 2017 an earthquake hit the city of Halabja which is located at Iraq-Iran border with the magnitude of 7.3 according to Richter scale. However, the damages still can be considered not that huge comparing to the intensity of the earthquake shake. Therefore, this paper has been carried out to investigate the effects of different soil profiles on the amount of damages and the behavior of buildings during earthquakes. In this paper the flexibility of soil or soil structure interaction (SSI) has not been considered and the conventional method (equivalent static lateral force procedure) which assumed that the structure is fixed at the base has been used for analysis. Three dimensional (3D) Model of eight storey residential building with plan dimensions of 20mX12m, each storey having a height of 3.2 m have been developed to analyze and compare the effect of seismic forces on multistory building by commercially available computer program, ETABS 2016. Various seismic parameters have been taken from ASCE7-10 and Iraqi Seismic code (ISC) 2014 for Halabja city and five soil profile types (SA, SB, SC, SD and SE) have been considered during analysis according to both codes. The base shears, storey moments, max story displacements, and inelastic storey drift responses with respect to change in storey level and soil conditions of the structure have been calculated. Based on the current paper, It has been observed that the soil profile type have significant influences on the behavior of the building during earthquakes. Additionally, the seismic forces are significantly reduced for harder soil profiles which could be one of the most important factors behind having small damages during Halabja earthquake.

Keywords: Soil Profile Types, RC Buildings, Standard Codes, Seismic Behaviour, Halabja City

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doi: 10.23918/eajse.v4i1sip149


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