土工基础 ›› 2019, Vol. 33 ›› Issue (6): 660-664.
南京牛首山滑坡体地层主要为侏罗系大王山组（J3d）火山成因凝灰岩，现场调查发现该滑坡历史上发生过较大变形，滑坡体曾发生过变形下滑现象。结合钻探结果对边坡水文地质结构分析发现，该岩层强风化导致高岭石化形成渗透性差的相对隔水层，且力学性质变差易导致边坡失稳。中风化岩层中裂隙发育，地表出露后有利于地表水下渗，在隔水层下部形成承压含水层。采用有限元法对降雨后地下水变化进行分析，发现在降雨强度为10～20 mm/d的条件下，持续4～6 d，边坡即可能达到极限状态。强风化岩层中超静孔隙压力不易于消散，导致边坡稳定性下降后长时间内不能恢复，边坡将保持一个较长的持续变形时间段。
The soil and rock strata of Niushuoshan landslide in Nanjing city, are mainly comprised of volcanic tuff of Jurassic Dawangshan Formation (J3d). Field investigation results showed that the landslide had historically undergone a large deformation, which is called an ancient landslide. The investigation results indicated that the highly weathered stratum leads to the formation of relatively impermeable kaolin aquitard layer, and the reduced mechanical properties result in the slope instability concerns. Cracks are well developed in moderately weathered strata, which are beneficial to the surface runoff seepage and to the formation of confined aquitard under the highly weathered stratum. The transient flow was evaluated by the finite element method, when the rainfall intensity reaches 10~20 mm/d and durations are between 4 and 6 days, the slope may reach its stability limit state. The excess pore pressure in the highly weathered strata is not easily to dissipate, which leads to a long period of continuous deformation of the slope and the stability could not be recovered in a short time.
摘要： 南京牛首山滑坡体地层主要为侏罗系大王山组（J3d）火山成因凝灰岩，现场调查发现该滑坡历史上发生过较大变形，滑坡体曾发生过变形下滑现象。结合钻探结果对边坡水文地质结构分析发现，该岩层强风化导致高岭石化形成渗透性差的相对隔水层，且力学性质变差易导致边坡失稳。中风化岩层中裂隙发育，地表出露后有利于地表水下渗，在隔水层下部形成承压含水层。采用有限元法对降雨后地下水变化进行分析，发现在降雨强度为10～20 mm/d的条件下，持续4～6 d，边坡即可能达到极限状态。强风化岩层中超静孔隙压力不易于消散，导致边坡稳定性下降后长时间内不能恢复，边坡将保持一个较长的持续变形时间段。
中图分类号:
