CAJ | 학술논문

以往对平面破坏模式的岩质边坡稳定性评价，主要关注潜在滑坡体在自重、坡体内静水压力和地震荷载耦合作用下沿破坏面的抗滑稳定性，并未涉及各类外荷载作用线不通过潜在滑体重心而引起的绕坡趾倾覆稳定性。针对这一问题，提出地震与张裂缝水压耦合作用下的岩质边坡倾覆稳定性解析方法，基于力矩平衡原理推导出岩质边坡抗倾覆稳定性系数的一般表达式；通过深入的变动参数比较研究，探讨张裂缝水压和地震荷载对抗倾覆安全系数的影响，认为水压是控制岩质边坡倾覆破坏的决定性因素，而地震荷载处于次要因素，其在一定程度上增加或减小抗倾覆稳定性。在此基础上建立不同参数组合下的岩质边坡抗倾覆稳定图，为工程技术人员快速评估饱水岩质边坡地震倾覆稳定性提供直接依据。
이왕대평면파배모식적암질변파은정성평개，주요관주잠재활파체재자중、파체내정수압력화지진하재우합작용하연파배면적항활은정성，병미섭급각류외하재작용선불통과잠재활체중심이인기적요파지경복은정성。침대저일문제，제출지진여장렬봉수압우합작용하적암질변파경복은정성해석방법，기우력구평형원리추도출암질변파항경복은정성계수적일반표체식；통과심입적변동삼수비교연구，탐토장렬봉수압화지진하재대항경복안전계수적영향，인위수압시공제암질변파경복파배적결정성인소，이지진하재처우차요인소，기재일정정도상증가혹감소항경복은정성。재차기출상건립불동삼수조합하적암질변파항경복은정도，위공정기술인원쾌속평고포수암질변파지진경복은정성제공직접의거。
The failure modes of rock slopes can be classified into five types:plane,wedge,circular, toppling,and buckling failures.These failure modes mainly depend on the lithological characteris-tics of the rock,properties of the discontinuities,and degree of weathering.Generally,rock slope stability analysis under the plane failure mode mainly focuses on the sliding stability of a potential sliding mass subjected to gravity,hydrostatic stress in the slope,and seismic loads.However,there exists the possibility of overturning failure around the toe of slopes because of the fact that all loadings do not act through the centroid of the sliding mass.This failure mode is completely dif-ferent from common topping failure,which involves the rotation of columns or blocks of rock about the fixed base,mainly occurring in anti-dipping layered rock mass slopes with steep dipping discontinuities.Thus,the existing methods for the stability assessment of the five common failure modes are no longer applicable,and a new method to determine the overturning failure is required. Note that although this overturning failure mode has not been observed and recorded,it is not im-possible under extreme rainfall conditions coupled with the strong ground motion in Southwest China.Aiming to resolve this issue,this study presents an analytical approach for the stability a-nalysis of overturning rock slopes.Considering the combined loadings mentioned above,the gener-alized analytical formula for the anti-overturning stability factor is derived based on the moment equilibrium theory.Based on the definition of the safety factor against overturning for earth-retai-ning structures,an anti-overturning stability factor is defined as the ratio of the resultant resistant moments to resultant driving moments.A comparative analysis by the variation of parameters was implemented,and the effects of the hydrostatic stress and seismic load on the anti-overturning stability factor of rock slopes are discussed.For a steep rock slope with a tension crack,the stabili-ty factor against overturning decreases rapidly from the infinitely great value for a dry slope to a finite value for a saturated slope.For the saturated rock slope,the safety factor against overturning changes significantly with the changes in the water pressure distribution.In addition,the vertical upward seismic force and horizontal seismic force on the slope face weaken the stability against o-verturning.It can be concluded that the hydrostatic stress in the tension crack plays a vital role in inducing the overturning failure and that the seismic load is secondary and can increase or decrease the possibility of overturning to a certain extent.On the basis of this,a series of preliminary charts for rock slope stability against overturning is produced and can be used to assess the seis-mic stability against overturning for saturated rock slopes.This series is produced by considering the different combinations of parameters such as the horizontal and vertical seismic coefficients, distribution modes of water pressure in the tension crack,and relative depth of tension cracks to the height of the slope.