Effect of short-term heavy rain on gravel soil slope stability of waste dump(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2016年06期
- Page:
- 39-47
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Effect of short-term heavy rain on gravel soil slope stability of waste dump
- Author(s):
- ZHENG Kai-huan; LUO Zhou-quan; LUO Cheng-yan; WANG Wei; HUANG Jun-jie; QIN Ya-guang
- 1. School of Resources and Safety Engineering, Central South University, Changsha 410083, Hunan， China; 2. Research Center of Safety and Health in Mine, Sinosteel Corporation Wuhan Safety ＆ Environmental Protection Research Institute, Wuhan 430081, Hubei, China
- Keywords:
- road engineering; waste dump; heavy rain; saturated-unsaturated seepage; matric suction; coupled stress-pore pressure analysis; safety factor
- PACS:
- U416.14
- DOI:
- -
- Abstract:
- In order to examine the effect of short-term heavy rain on stability of layered gravel soil slope of waste dump, firstly, saturated-unsaturated seepage analysis was carried out to obtain distribution of pore water pressure within the slope at different time using SEEP/W. Then distribution of pore water pressure within the slope was imported to SIGMA/W and SLOPE/W to carry out coupled stress-pore pressure analysis and slope stability analysis. At last, slope failure mechanism after rain was analyzed through the comparison of pore water pressure within the slope at different time after rain. The results show that surface of slope is most remarkably affected by heavy rain. The matric suction of surface of slope decreases rapidly from surface to deep slope along with the increase of water content. After rain, the matric suction of surface of slope increases rapidly first, and then increases with a relatively lower rate. Surface of slope has the largest seepage velocity due to its high permeability. If there exists a water-resisting layer in the bottom, water will come out of the slope from the slope toe with a rising flow rate and ground water level during the rain. The largest displacement increases rapidly first, and then increases with a decreasing rate during the rain and keeps increasing after the rain. The safety factor of slope decreases rapidly during the rain. After rain, the critical slip surface moves to the bottom of surface of slope, which has a lower matric suction due to water infiltration. Moreover, the safety factor of slope keeps going down to the minimum before it increases. It is most possible for the layered gravel soil slope of waste dump to fail shortly after short-term heavy rain.
Last Update: 2016-12-02