An Analytical Study on the Relationship between Factor of Safety and Horizontal Displacement of Soil Nailed Walls

쏘일네일 보강벽체의 수평변위와 안전율과의 관계 분석연구

  • Kim, Hongtaek ;
  • Lee, In
  • 김홍택 (홍익대학교 토목공학과) ;
  • 이인 (홍익대학교 토목공학과)
  • Received : 2010.11.15
  • Accepted : 2010.12.23
  • Published : 2011.02.01

Abstract

Soil nailing method was often designed by the slope stability analysis based on limit equilibrium. However, in the case of shorten length of nails, although the calculated factor of safety is within the design factor of safety, the horizontal displacement of soil nailed walls occurred above the allowable limit. In this study, relationship between the load and factor of safety, and relationship between the load and displacement ratio based on the test results were analysed. From the analysed results, the relationship between factor of safety and displacement ratio was estimated. For the mobilized horizontal displacement of the walls within the serviceability limit corresponding to the displacement of less than 0.3% displacement ratio, the calculated factor of safety by limit equilibrium analysis had to satisfy above 1.35. Also, although the minimum factor of safety is estimated above 1.35, the maximum horizontal displacement is often mobilized above 0.3% of excavation height. Therefore, it is necessary to perform the numerical analysis of soil nailed walls in the case of low shear strength or high excavation.

Acknowledgement

Supported by : 홍익대학교

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