One dimensional equivalent linear ground response analysis - A case study of collapsed Margalla Tower in Islamabad during 2005 Muzaffarabad Earthquake

Khalid Mahmood, Zia ur Rehman Rehman, Khalid Farooq, Shazim Ali Memon

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

One dimensional equivalent linear ground response analysis was conducted in the Margalla Tower building in Islamabad, which collapsed during 2005 Muzaffarabad Earthquake. The analyses were conducted in DEEPSOIL software, without considering the effect of ground water table. The input subsoil data were selected from laboratory and field tests conducted for the site with bedrock at a depth of 21 m as per site condition. The field and laboratory testing data showed that the subsoil beneath the Tower site was silty clay to lean clay according to the unified soil classification system. Four different accelerograms with PGA values of 0.17 g, 0.15 g, 0.22 g and 0.21 g, compatible with the earthquake in the target area were applied at the bedrock. The surface response spectra showed that, except the Accelerogram-1 all other three were amplified near the fundamental period of the site. The analyses showed that different PGA values (0.26 g, 0.21 g, 0.36 g and 0.21 g) were produced at the surface which can be explained due to the difference in the Fourier amplitude of input accelerograms. Furthermore, the different input accelerograms produced a different shear strain and thus mobilized different shear strengths along the soil profile depth. Finally, the calculated response spectra of accelerograms were compared with the response spectra of Islamabad. The calculated spectral acceleration values were found to be higher than reported by the Building Code of Pakistan (0.16 g to 0.24 g).

Original languageEnglish
Pages (from-to)110-117
Number of pages8
JournalJournal of Applied Geophysics
Volume130
DOIs
Publication statusPublished - Jul 1 2016
Externally publishedYes

Fingerprint

Kashmir earthquake 2005
response analysis
towers
earthquakes
subsoil
bedrock
clays
soils
soil classification
silty clay
shear strain
water tables
Pakistan
shear strength
soil profile
water table
field tests
ground water
software
clay

Keywords

  • Fourier amplitude spectrum
  • Geotechnical investigation
  • Ground response analysis
  • Response spectrum

ASJC Scopus subject areas

  • Geophysics

Cite this

One dimensional equivalent linear ground response analysis - A case study of collapsed Margalla Tower in Islamabad during 2005 Muzaffarabad Earthquake. / Mahmood, Khalid; Rehman, Zia ur Rehman; Farooq, Khalid; Memon, Shazim Ali.

In: Journal of Applied Geophysics, Vol. 130, 01.07.2016, p. 110-117.

Research output: Contribution to journalArticle

@article{5e7d4e5ce16f45b999a5d3f5bd190131,
title = "One dimensional equivalent linear ground response analysis - A case study of collapsed Margalla Tower in Islamabad during 2005 Muzaffarabad Earthquake",
abstract = "One dimensional equivalent linear ground response analysis was conducted in the Margalla Tower building in Islamabad, which collapsed during 2005 Muzaffarabad Earthquake. The analyses were conducted in DEEPSOIL software, without considering the effect of ground water table. The input subsoil data were selected from laboratory and field tests conducted for the site with bedrock at a depth of 21 m as per site condition. The field and laboratory testing data showed that the subsoil beneath the Tower site was silty clay to lean clay according to the unified soil classification system. Four different accelerograms with PGA values of 0.17 g, 0.15 g, 0.22 g and 0.21 g, compatible with the earthquake in the target area were applied at the bedrock. The surface response spectra showed that, except the Accelerogram-1 all other three were amplified near the fundamental period of the site. The analyses showed that different PGA values (0.26 g, 0.21 g, 0.36 g and 0.21 g) were produced at the surface which can be explained due to the difference in the Fourier amplitude of input accelerograms. Furthermore, the different input accelerograms produced a different shear strain and thus mobilized different shear strengths along the soil profile depth. Finally, the calculated response spectra of accelerograms were compared with the response spectra of Islamabad. The calculated spectral acceleration values were found to be higher than reported by the Building Code of Pakistan (0.16 g to 0.24 g).",
keywords = "Fourier amplitude spectrum, Geotechnical investigation, Ground response analysis, Response spectrum",
author = "Khalid Mahmood and Rehman, {Zia ur Rehman} and Khalid Farooq and Memon, {Shazim Ali}",
year = "2016",
month = "7",
day = "1",
doi = "10.1016/j.jappgeo.2016.04.015",
language = "English",
volume = "130",
pages = "110--117",
journal = "Journal of Applied Geophysics",
issn = "0926-9851",
publisher = "Elsevier",

}

TY - JOUR

T1 - One dimensional equivalent linear ground response analysis - A case study of collapsed Margalla Tower in Islamabad during 2005 Muzaffarabad Earthquake

AU - Mahmood, Khalid

AU - Rehman, Zia ur Rehman

AU - Farooq, Khalid

AU - Memon, Shazim Ali

PY - 2016/7/1

Y1 - 2016/7/1

N2 - One dimensional equivalent linear ground response analysis was conducted in the Margalla Tower building in Islamabad, which collapsed during 2005 Muzaffarabad Earthquake. The analyses were conducted in DEEPSOIL software, without considering the effect of ground water table. The input subsoil data were selected from laboratory and field tests conducted for the site with bedrock at a depth of 21 m as per site condition. The field and laboratory testing data showed that the subsoil beneath the Tower site was silty clay to lean clay according to the unified soil classification system. Four different accelerograms with PGA values of 0.17 g, 0.15 g, 0.22 g and 0.21 g, compatible with the earthquake in the target area were applied at the bedrock. The surface response spectra showed that, except the Accelerogram-1 all other three were amplified near the fundamental period of the site. The analyses showed that different PGA values (0.26 g, 0.21 g, 0.36 g and 0.21 g) were produced at the surface which can be explained due to the difference in the Fourier amplitude of input accelerograms. Furthermore, the different input accelerograms produced a different shear strain and thus mobilized different shear strengths along the soil profile depth. Finally, the calculated response spectra of accelerograms were compared with the response spectra of Islamabad. The calculated spectral acceleration values were found to be higher than reported by the Building Code of Pakistan (0.16 g to 0.24 g).

AB - One dimensional equivalent linear ground response analysis was conducted in the Margalla Tower building in Islamabad, which collapsed during 2005 Muzaffarabad Earthquake. The analyses were conducted in DEEPSOIL software, without considering the effect of ground water table. The input subsoil data were selected from laboratory and field tests conducted for the site with bedrock at a depth of 21 m as per site condition. The field and laboratory testing data showed that the subsoil beneath the Tower site was silty clay to lean clay according to the unified soil classification system. Four different accelerograms with PGA values of 0.17 g, 0.15 g, 0.22 g and 0.21 g, compatible with the earthquake in the target area were applied at the bedrock. The surface response spectra showed that, except the Accelerogram-1 all other three were amplified near the fundamental period of the site. The analyses showed that different PGA values (0.26 g, 0.21 g, 0.36 g and 0.21 g) were produced at the surface which can be explained due to the difference in the Fourier amplitude of input accelerograms. Furthermore, the different input accelerograms produced a different shear strain and thus mobilized different shear strengths along the soil profile depth. Finally, the calculated response spectra of accelerograms were compared with the response spectra of Islamabad. The calculated spectral acceleration values were found to be higher than reported by the Building Code of Pakistan (0.16 g to 0.24 g).

KW - Fourier amplitude spectrum

KW - Geotechnical investigation

KW - Ground response analysis

KW - Response spectrum

UR - http://www.scopus.com/inward/record.url?scp=84966431040&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84966431040&partnerID=8YFLogxK

U2 - 10.1016/j.jappgeo.2016.04.015

DO - 10.1016/j.jappgeo.2016.04.015

M3 - Article

VL - 130

SP - 110

EP - 117

JO - Journal of Applied Geophysics

JF - Journal of Applied Geophysics

SN - 0926-9851

ER -