Geomechanics and Engineering

  • 제14권1호
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  • Pages.43-50
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  • 2018
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  • 2005-307X(pISSN)
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  • 2092-6219(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

Evaluation of performance of piled-raft foundations on soft clay: A case study

  • Khanmohammadi, Mohammadreza (Department of Civil and Environmental Engineering, Amirkabir University of Technology) ;
  • Fakharian, Kazem (Department of Civil and Environmental Engineering, Amirkabir University of Technology)
  • 투고 : 2016.12.01
  • 심사 : 2017.06.22
  • 발행 : 2018.01.20
⟨ 이전 논문 다음 논문 ⟩

초록

Applicability of constructing piled raft foundations on soft clay has been given attention in recent years. Lack of sufficient stiffness for soil and thus excessive settlements to allow higher contribution of piles is the major concern in this regard. This paper presents a numerical investigation of performance of piled-raft foundations on soft clay with focusing on a case study. A 3D FEM numerical model is developed using ABAQUS. The model was calibrated by comparing physical and numerical modeling results of other researchers. Then the possibility of using piled-raft system in construction of foundation for a water storage tank in Sarbandar, Iran is assessed. Soil strength parameters in the numerical model were calibrated using the instrumentation data of a heavily instrumented preloading project at the construction site. The results indicate that choosing the proper combination of length and spacing for piles can lead to acceptable differential and total settlements while a high percentage of total bearing capacity of piles can be mobilized, which is an efficient solution for the project. Overall, the construction of piled-rafts on soft clays is promising as long as the total settlement of the structure is not imposing restrictions such as the common 25 mm allowable settlement. But instead, if higher allowable settlements are adopted, for example in the case of rigid steel tanks, the method shall be applicable with considerable cost savings.

키워드

참고문헌

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피인용 문헌

  1. Behavior of a combined piled raft foundation in a multi-layered soil subjected to vertical loading vol.21, pp.4, 2020, https://doi.org/10.12989/gae.2020.21.4.379
  2. Measurements and analysis of load sharing between piles and raft in a pile foundation in clay vol.24, pp.6, 2021, https://doi.org/10.12989/gae.2021.24.6.559
  3. Assessment of ultimate load of drilled shaft socketed in rocks based on pile load tests vol.26, pp.3, 2018, https://doi.org/10.12989/gae.2021.26.3.215