摘要
研究岩质顺层滑坡发育规律对岸坡稳定有重要意义。以三峡库区秭归县沙镇溪镇为研究区,在野外调查和数理统计基础上,分析了岩质顺层滑坡的岸坡结构、空间分布和滑面形态。结果表明,该区主要发育缓倾顺层坡和中倾顺层坡;岩质顺层滑坡均发育在侏罗系软弱互层地层中,软弱夹层对滑坡稳定性起控制性作用;折线式滑坡地层倾角为30°~40°,一般发育在中倾顺层坡中,下滑力主要为滑坡中后部滑体重力,滑坡前部为阻滑段,主要受库水位上升影响。直线式滑坡地层倾角约20°,一般发育在缓倾顺层坡中,下滑力主要为滑体重力,抗滑力主要来自滑带抗剪强度,主要受降雨影响。研究成果可为岩质顺层岸坡滑坡稳定性评价和预警预报提供参考。
The research on development regularity of rock bedding landslide has a great significance of bank slope stability.Three Gorges Reservoir Area of Shazhenxi Village was selected as a study area.The bank structure,spatial distribution and morphological of slip surface were analyzed on the basis of field investigation and mathematical statistics.The results show that the study area mainly developed gently inclined bedding slope and medium-dip bedding slope.Rock bedding slope is developed in Jurassic rock sandwich and the rock sandwich plays a controlling role in landslide stability.The polyline landslide formation dip is between 30°-40°and often develops medium-dip bedding slope.The slippage force is mainly for the rear part of the landslide and the front part of the landslide is the resistance slip section.The polyline landslide mainly affected by reservoir water level rise.The linear landslide formation dip is about 20°and often develops in gently inclined bedding slope.The slippage force is mainly for the part of the landslide and the resistance force mainly comes from the shear strength of the sliding belt.The linear landslide mainly affected by rainfall.The research results can provide references for stability evaluation and warning forecast of rock bedded landslide.
引文
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