以河南省灵宝市麦尖窝滑坡作为试验对象,进行室内人工降雨模型试验,研究降雨作用下牵引式滑坡的变形破坏规律,并提出适用于研究区的降雨预警判据。采用含水率传感器、坡面示踪点和数码相机等仪器设备对关键部位含水率、坡面变形和裂缝发育情况进行监测、记录。试验表明在强降雨作用下,边坡表现为自下而上的渐进式牵引变形破坏。通过分析模型各关键部位的变形破坏特征和含水率监测数据,确定牵引式滑坡变形破坏过程中的关键时间节点,并将整个过程划分为变形启动、变形加速和整体破坏3个阶段。基于以上变形破坏模式,提出以滑坡坡脚、坡肩表面出现贯通裂缝时的持续累计雨量E1(75 mm)、E2(180 mm)分别作为麦尖窝滑坡的橙色、红色降雨预警判据。
Abstract
Indoor artificial rainfall simulation test was conducted to investigate the mechanism of retrogressive landslide, and the criteria of rainfall warning for the study were proposed. The Maijianwo landslide in Lingbao City of Henan Province was taken as a case study. In the model test, moisture sensors, tracking points and digital cameras were adopted to record variations in the moisture of crucial parts, the surface deformation and crack propagation. Research results showed that the rainstorm led to destruction from the bottom of slope to the top gradually as a retrogressive mode. The slope failure process was divided into three stages as deformation activation, deformation acceleration and integral destruction in accordance with the critical time points by analyzing the deformation characteristics and moisture monitoring data of crucial parts. According to the above failure mode, the cumulative rainfalls E1 (75mm) and E2 (180mm) were respectively set as the orange and red warning criteria for the Maijianwo landslide when there were penetrating cracks on the slope toe and shoulder.
关键词
牵引式滑坡 /
模型试验 /
累计雨量 /
破坏规律 /
预警判据
Key words
retrogressive landslide /
model test /
cumulative rainfall /
destruction regularity /
warning criteria
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参考文献
[1] 周创兵,李典庆.暴雨诱发滑坡致灾机理与减灾方法研究进展[J].地球科学进展,2009,24(5):477-487.
[2] 周跃峰,龚壁卫,胡 波,等.牵引式滑坡演化模式研究[J].岩土工程学报, 2014, 36(10):1855-1862.
[3] 祝廷尉,胡新丽,徐 聪,等. 嵌岩桩抗滑特性的物理模型试验研究[J].岩土力学,2014,35(S1):165-172.
[4] 罗先启,刘德富,吴 剑,等.雨水及库水作用下滑坡模型试验研究[J].岩石力学与工程学报,2005, 24(14):2476-2483.
[5] 武彩萍,骆亚生,陈 伟,等. 降雨对黄土裸坡坡面形态影响的室内模型试验[J].水土保持通报,2013,33(1):115-119.
[6] 林鸿洲,于玉贞,李广信,等.降雨特性对土质边坡失稳的影响[J].岩石力学与工程学报,2009,28(1):198-204.
[7] 张 敏,吴宏伟.边坡离心模型试验中的降雨模拟研究[J].岩土力学, 2007,28(S):53-57.
[8] 吴树仁,金逸民,石菊松,等.滑坡预警判据初步研究——以三峡库区为例[J].吉林大学学报(地球科学版),2004,34(4):596-600.
[9] 亓 星,许 强,孙 亮,等.降雨型黄土滑坡预警研究现状综述[J].地质科技情报,2014,33(6):219-225.
[10]唐亚明,薛 强,毕俊擘,等.降雨入渗诱发黄土滑塌的模式及临界值初探[J].地质论评,2013,59(1):97-106.