【摘要】 马铃岩滑坡位于唐家山堰塞湖内上游约4 km的通口河左岸,在堰塞湖抢险过程中备受关注。在对滑坡基本地质条件和地震前、后变形破坏迹象现场地质调查基础上,对震后、尤其是唐家山堰塞湖形成后滑坡稳定性进行了系统分析和计算。计算结果表明,各种不同工况下震后滑坡整体稳定,只是靠上游侧前缘受地震、堰塞湖蓄水及泄水水位骤降等因素影响存在局部失稳,马铃岩滑坡不会对下游唐家山堰塞坝溃坝以及未来堰塞湖综合治理工程产生不利影响,但震后重建工作中应注意靠上游侧滑坡体前缘一带不稳定对坡体上数十户居民造成的潜在危害。就马铃岩及地震重灾区其他古滑坡体而言,地震对大型古滑坡复活主要受控于其地形坡度及微地貌特征,地形坡度40°以上以及由缓变陡的转折部位是古滑坡整体或局部容易被地震触发失稳的充分条件,并非所有的古滑坡体均会被地震诱发而整体复活。更多还原

【Abstract】 Malingyan Landslide is located in the left bank of Tongkou River,which is 4 km away from the upstream of Tangjiashan dammed lake.Because of its special location,it receives much concern in the process of dealing with an emergency of the dammed lake.Based on the field geological investigations of basic landslide geological conditions,deformation and failure characteristics before and after Wenchuan 8.0 earthquake,stability of Malingyan landslide,especially after the formation of dammed lake,is analyzed.The results show that the landslide is generally stable after earthquake,but part of the former section of the upriver is possibly instable because of earthquake and water storage of the dammed lake and so on.Malingyan landslide will not put against Tangjiashan dammed lake and the comprehensive treatment at a disadvantage in the future can be saved,but more attention should be put on the former section of the landslide as it may be partially instable as a result of continuous rainfalls as well as the earthquakes.And then,the potential sliding on the upside may be harmful to some residents on the slope body.Based on analytical stability results of Malingyan and the other landslides in earthquake areas,the overall reactivation of the large-scale ancient landslide caused by earthquake is mainly controlled by its terrain slope and micro-geomorphic characteristics.The whole or part ancient landslides triggered by earthquake will be instable if it satisfies the sufficient condition,in which the terrain slope is above 40 °as well as slow part changes into steep one.Not all ancient landslides are possibly reactivated by the earthquake,and this will tremendously change the common misunderstanding in the past that the earthquake will trigger the whole ancient landslide reactivated inevitably.更多还原