关键词: 封面土, 膨胀土, 边坡稳定性系数, 土工膜, 路基

Abstract: Use of veneer cover soil on the side slope of expansive soil subgrade is a method to prevent early failure of expansive soil subgrade.But the interface between the veneer cover soil and the subgrade becomes a new weak point to the whole subgrade.That leads to another stability problem of veneer cover soil its own.To the problem of analyzing the stability of veneer cover soil of equal thickness,the most commonly used methods are based on the assumption that slopes were infinite in length. But the side slopes of subgrade are finite in length,so these methods may not be suitable to be used in that case.Through laboratory study,it is found that the actual sliding surface occurred in veneer cover soil on finite slope is different from that of commonly used methods mentioned above.According to the actual sliding surface from laboratory study,this paper develops a new formula for calculating the stability factor of veneer cover soil on the side slope of expansive soil suograde.In the end,some conclusions are also presented.

Key words: veneer cover soil, expansive soil, stability factor of slope, geo membrane, subgrade