Case Study on the Reinforcement of Rock Slopes considering the Orientation of Bedding Planes Relative to the Slope

Jaeyoung Park; Jongwoo Kim

doi:10.9720/kseg.2025.1.095

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2025 Vol.35, Issue 1 Preview Page Next Page

Research Article

Case Study on the Reinforcement of Rock Slopes considering the Orientation of Bedding Planes Relative to the Slope 층리면의 방향성을 고려한 암반비탈면 보강 사례 연구

31 March 2025. pp. 95-105

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Abstract

We examined the stability of a slope given the difference in the orientation of the slope and the bedding plane, and changes in slope stability in cross sections oriented normal to the road surface and normal to bedding when reinforcing the slope. The results show that when the difference between the dip of the slope and the bedding surface is 0~30°, the safety factor of the slope decreases to 91.2~96.6% as the difference in the dip directions increases. In particular, we calculated that the slope is unstable when the difference in the dip directions is ≥20°. Applying the same reinforcement conditions to the cross-sections oriented normal to the road surface and the bedding plane, we calculated the safety factor of the cross-section oriented normal to the bedding plane to be 72.0~91.6% of the safety factor of the cross-section oriented normal to the road surface, and the safety factor of the slope was reduced by 8.4~28.0%, depending on the change in cross-section. Therefore, when examining a slope with bedding planes a reinforcement plan that considers the slope direction is necessary to ensure the stability of the slope depending on the reduction in reinforcement force and cross-section change. Slope data considering the dip direction, as presented in this study, can be used as a reference for future reinforcement plans for sedimentary rocks.

Keywords

sedimentary rock

bedding

dip

dip direction

reinforcement force

본 연구에서는 비탈면과 층리면의 경사방향 차이에 따른 비탈면의 안정성과 도로면에 수직인 단면과 층리면에 수직인 단면에서 비탈면 보강시 비탈면의 안정성 변화를 검토하였다. 연구결과 비탈면과 층리면의 경사방향 차 0~30° 시 비탈면의 안전율은 경사방향의 차이가 증가될수록 약 91.2~96.6% 내외로 감소되는 것으로 분석되었다. 특히, 경사방향 ≥20°일 경우 비탈면의 안정성은 확보되지 못하는 것으로 분석되었다. 도로면과 층리면에 수직인 단면에 동일한 보강 조건을 적용한 결과, 층리면의 수직인 단면의 안전율은 도로면에 수직인 단면 안전율의 72.0~91.6%로 산정되었으며, 비탈면의 안전율은 단면변화에 따라 8.4~28.0% 감소되는 것으로 검토되었다. 따라서, 층리면이 있는 비탈면 검토시 보강력 감소와 단면 변화에 따른 비탈면의 안정성을 확보하기 위해 비탈면 방향성을 고려한 보강 계획이 필요하다. 본 연구에서 제시한 경사방향을 고려한 비탈면 연구자료는 향후 퇴적암에 대한 보강계획시 참고자료로 활용될 수 있을 것으로 판단된다.

키워드

퇴적암

층리

경사

경사방향

보강력

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Information

Publisher :Korean Society of Engineering Geology
Publisher(Ko) :대한지질공학회
Journal Title :The Journal of Engineering Geology
Journal Title(Ko) :지질공학
Volume : 35
No :1
Pages :95-105
Received Date : 2025-03-04
Revised Date : 2025-03-21
Accepted Date : 2025-03-26
DOI :https://doi.org/10.9720/kseg.2025.1.095

The Journal of Engineering Geology ISSN:1226-5268(Print) 2287-7169(Online) 지질공학

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