基于SEEP/W的强震区根系土坡面物源失稳机制分析  

Analysis of Provenance Instability Mechanism of Root System Soil Slope in Strong Earthquake Area Based on SEEP/W

作　　者：黄琛 张友谊[1] 叶小兵 Huang Chen;Zhang Youyi;Ye Xiaobing(School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang Sichuan 621010,China;Sichuan Geological Engineering Survey Group Co.,Ltd,Chengdu 610032,China)

机构地区：[1]西南科技大学土木工程与建筑学院,四川绵阳621010 [2]四川省地质工程勘察院集团有限公司,成都610032

出　　处：《科技通报》2022年第7期57-66,72,共11页Bulletin of Science and Technology

基　　金：国家重点研发计划(2018YFC1505401);国家自然科学基金面上项目(41971214)。

摘　　要：“5.12”汶川特大地震破坏山体地质结构,引发大量同震滑坡,产生的大量坡面松散物源为震后泥石流发育提供充足条件。本文通过有限元数值模拟(SEEP/W模块)研究含草本植被的根系土边坡对渗流场、位移场、应力场的影响。研究表明:(1)强震区浅表层上部土体更易发生失稳滑塌,含草本根系土能有效减缓边坡上部土体失稳现象;(2)坡体在40°时,含草本根系对强震区坡面物源固土效果最佳,位移抑制率约55%;(3)T=3600 s前,坡体在50°时位移抑制率最高,此时根—土复合体土壤入渗率较低;(4)随坡度的增大,含草本根系对覆盖层前、中、后期的影响呈负相关;(5)缓坡坡面物源失稳形式为冲刷沟蚀,陡坡为整体失稳。The "5.12" Wenchuan earthquake destroyed the geological structure of the mountain and caused a large number of co-seismic landslides.The large number of loose slope sources produced provide sufficient conditions for the development of debris flow after the earthquake.This paper uses finite element numerical simulation(SEEP/W module) to study the influence of herbaceous vegetation root soil slope on seepage field,displacement field and stress field.Researches show that:(1) The upper soil of the shallow surface layer in the strong earthquake area is more prone to instability and collapse,and the soil with herb root system can effectively slow down the instability of the upper soil of the slope;(2) When the slope is at 40°,the herb-bearing root system has the best soil consolidation effect on the slope provenance in the strong earthquake area,with a displacement inhibition rate of about 55%;(3) Before T=3600 s,the slope has the highest displacement inhibition rate at 50° At this time,the soil infiltration rate of the root-soil complex is low;(4) With the increase of slope,the influence of herbaceous roots on the front,middle and later stages of the overburden is negatively correlated;(5) The instability form of provenance on the gentle slope is erosion of gully,and that on the steep slope is overall instability.

关 键 词：坡面物源 根系护坡 边坡稳定性 数值模拟 瞬态渗流 

分 类 号：TU43[建筑科学—岩土工程]