Analysis of collapse course of mudstone cut slope and suggest countermeasure

이암 절토 사면의 붕괴 요인 분석 및 대책방안 제시

  • Park, Min-Cheol (Department of Civil Engineering, Kumoh Institute of Technology)
  • 박민철 (금오공과대학교 토목공학과)
  • Received : 2018.02.07
  • Accepted : 2018.04.06
  • Published : 2018.04.30


This study analyzed the collapse course of a mud stone cut slope during the construction of a express and suggested a countermeasure. Experiments were carried out on bedrock mudstone to investigate the engineering characteristics and the slope stability analysis at the time the design was reviewed. In addition, stability analysis, considering the strength softening characteristics of the slope due to the Swelling-Slaking phenomenon, was also performed. As a result of the Swelling-Slaking test, the slake durability was Low-Medium, and the swell potential was Very Low. A review of the stability analysis performed at the time of the design showed different results from the actual results because LEM analysis had been performed without considering the engineering characteristics of mudstone. As a result of additional stability analysis considering the strength softening characteristics, the slope collapse point and the maximum shear strain point of the stability analysis were the same and the standard safety factor was not satisfied. As a countermeasure, a slope mitigation method was found to be most appropriate. The mitigation slope was calculated by Finite element Analysis. A comparison with BIPS to determine the applicability of a mitigation slope revealed most of the unconsolidated mudstone.


Mudstone slope;Slope collapse;Swelling;Slaking;Slope Stability Analysis


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