岩溶地基稳定性评价中应注意的几个问题

在岩溶地基稳定性评价中,现有规范所推荐的方法,没有考虑下覆溶洞或土洞的规模尺寸、地下水、地基土层等因素对地基稳定性的影响;塌陷松胀物自行堵塞填满洞体后,将会构成地基的软弱下卧层,降低地基承载力; 运用坍塌平衡法计算,应考虑土洞平面形状的影响,同时土层的内聚力c不能被忽略;普氏压力拱理论计算公式, 没有考虑岩土体的凝聚力作用,而且其具有较大的安全储备。

SEVERAL ISSUES SHOULD BE PAID ATTENTION ON SUBSOIL STABLITY APPRAISEMENT IN KARST REGION

In the process of stability appraisemen for Karst subsoil, the effects on subsoil stability caused by some factors such as the dimension of cave, groundwater and soil component, have not been taken into account in the method recommended by code. The filling because of cave collapse will become weak underlying stratum in subsoil, and bearing capacity of subsoil will decrease. The plane shape of soil cave should be taken into account in using' collapse balance method', in the meantime, the cohesion c should not be neglected. The action of soil cohesion has not been included in the theory calculation formula of πpoTogbaKOHOB's pressure arch', and the result of calculation will be more safe.