Evaluating the Effect of Concrete Pedestal on Reducing the Vulnerability of Adjacent Footings on Babolsar Saturated Sand Using Physical Model Tests

Document Type : Research Paper

Authors

1 Ph.D. Candidate, Department of Civil Engineering, Islamic Azad University, Najafabad Branch, I. R. Iran.

2 Associate Professor, Geotechnical Engineering Research Center, International Institute of Earthquake Engineering and Seismology, Tehran, I. R. Iran.

3 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran.

Abstract

Two adjacent footings behave often differently from a single footing. Nowadays, with the scarcity of suitable land for construction purposes and population growth in the coastal zone of Caspian Sea, construction without considering the interference of the footings is increasing. This issue has been further complicated due to the unequal and non-simultaneous loading of the adjacent footings. In other words, initially, the light or old footing has been constructed, and then the heavy or new footing will be constructed adjacent to the old footing. This is also true in ports where containers are stacked side by side. In this study, the influence of unreinforced concrete pedestals on improvement of saturated loose sandy soil is investigated through modeling the small-scale 1g tests. The main focus was on the load bearing capacity, settlement and tilt of the light footing nearby the heavy footing, when the pedestals are placed beneath the heavy footing. Results of this study illustrated that with fixed diameter pedestals (D=5 cm), increasing the pedestal length (L) from 15 to 25 cm, as refining factor of the soil underneath the heavy footing, led to 18 and 38 percent decrease in settlement and tilt of the light footing nearby the heavy one, respectively, when the S/B ratio was zero.

Keywords

References

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Journal of Transportation Infrastructure Engineering
Volume 4, Issue 2 - Serial Number 14
September 2018
Pages 49-60

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History

  • Receive Date: 09 June 2018
  • Revise Date: 08 July 2018
  • Accept Date: 17 July 2018

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