Geomechanics and Engineering

  • 제38권3호
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  • Pages.285-305
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  • 2024
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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

Analytical and ANN-based models for assessment of hunchback retaining walls: Investigating lateral earth pressure in unsaturated backfill

  • 투고 : 2024.05.04
  • 심사 : 2024.07.23
  • 발행 : 2024.08.10
⟨ 이전 논문 다음 논문 ⟩

초록

This study investigates the behaviour of hunchback retaining walls supporting unsaturated sandy backfill under active earth pressure conditions. Utilizing a horizontal slice method and a unified effective stress methodology, the influence of various factors on lateral earth pressure, including the position of the hunch along the wall, friction angles, and wall heights, is explored. The results suggest that relocating the hunch position from close to the wall's top to near its base leads to a significant decrease (ranging from 54% to 81%) in lateral earth pressure. However, as the hunch position transitions from near the top to mid-height, the point of application of active thrust shifts upward initially, then slightly downward as the hunch position approaches the toe. Notably, the reduction in lateral earth pressure is more pronounced for shorter wall heights and higher friction angles. Building upon these findings, an Artificial Neural Network (ANN)-based model is developed to accurately predict the lateral earth pressure coefficient and point of application, achieving R2 values of 0.94 and 0.93, respectively. In addition, an analytical model based on Coulomb's earth pressure theory is presented and compared with ANN models. These models are anticipated to assist designers and practitioners in optimizing hunchback retaining walls for unsaturated backfill.

키워드

참고문헌

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