【摘要】 甘肃黑方台滑坡群沿台塬周边发育密集,发生频次高。从地形地貌及坡体几何特征、地质结构与控滑结构面、岩土体组合及其工程性质和水文地质条件等内在因素分析了滑坡发生的控制条件;从灌溉和冻融作用方面分析了滑坡的外动力驱动因素。新构造运动的间歇性抬升所塑造的现今黄土台塬与黄河二级阶地陡坎相接的地貌格局,以及四周台缘较大的地势高差为滑坡的形成奠定了地形条件,由黄土-基岩组成的多层坡体结构中不仅存在易滑地层,且下伏基岩存在顺向软弱夹层,从而在灌溉及冻融等因素共同作用下引发了众多滑坡,因斜坡几何形态和坡体岩土组合、控滑结构面的出露位置、水文地质条件的差异,不同区段滑坡发育特征及成灾模式也不尽相同。更多还原

【Abstract】 Heifangtai landslides are concentrated in the surroundings of Loess Platform,Gansu province,with high occurrence frequency.The internal control factors for landslides have been analyzed in this paper,including the topography and geomorphology,geometrical characteristics of landslides body,geological structure,landslides controlling structure surface,rock and soil group of slope body,engineering and hydrological conditions.The external force has also been researched from the aspects of irrigation and freeze-thaw.The intermittent neotectonic uplift movement has shaped the geomorphic pattern of the loess platform connected with the second terrace of the Yellow River and the large elevation difference at the edge of the platform,all of these have been established as the geomorphic basis for the formation of landslides.Multi-slope structure of loess and rock exists in the easily sliding stratum and consequentsoft interlayer.So,the combined action of irrigation and freeze-thaw has induced the landslides.The development and disaster mode is deferent due to the various geometrical characteristics of landslides body,rock and soil group of slope,the position of the landslide controlling structure surface,hydrological conditions.更多还原