土工基础

›› 2015, Vol. 29 ›› Issue (5): 35-38.

• 工程实录 • 上一篇    下一篇

残积土坡降雨渗流特性与排水设计数值研究

沈孟兴,樊秀峰   

  1. （福州大学环境与资源学院，福州 350108）
  • 收稿日期:2014-11-13 出版日期:2015-10-20 发布日期:2015-11-06
  • 作者简介:沈孟兴（1990-），男，福州大学硕士研究生，研究方向为边坡工程。
  • 基金资助:

    基金项目：福建省自然科学基金资助（2012J01170），福建省地质灾害重点实验室开放基金资助（FJKLGP2012K002）

A Numerical Analysis of the Rainfall-Induced Seepage and Drainage System for a Residual Soil Slope

SHEN Mengxing, FAN Xiufeng   

  1. (College of Environment and Resources, Fuzhou University, Fuzhou 350108)
  • Received:2014-11-13 Online:2015-10-20 Published:2015-11-06

摘要： 大气降雨是触发边坡失稳的重要因素之一，合理排水可有效控制渗流、稳定边坡。针对福建典型的非饱和花岗岩残积土坡，基于饱和-非饱和渗流理论，分析研究降雨入渗条件及不同排水方式对渗流场控制规律及对边坡稳定性的影响规律。结果表明，降雨条件下存在临界降雨强度，在此强度内，边坡浅表处的最大孔隙水压力和地下水位均随降雨历时和降雨强度的增加而增加，坡脚渗流密集。水平排水管设置对边坡整体稳定性影响显著，最优排水管长度约为单级边坡的水平投影长度，排水管角度在工程中以10°为宜，坡顶坡底双层排水效果更佳。

关键词: 非饱和残积土, 降雨, 渗流, 水平排水

Abstract: The precipitation is one of the important factors that triggering the slope failure. Therefore, a welldesigned drainage system is needed to manage the seepage flow and to stabilize the slope. The seepage characteristics and stability aspects of a typical residuum slope of granite origin under different drainage patterns are analyzed by using the saturated and unsaturated seepage theories. The results indicate that a critical precipitation intensity exists in the seepage drainage patterns. If the rainfall intensity is within this value, the maximum pore pressure at the shallow depth and the groundwater table are increasing with the duration and the precipitation intensity. The seepages are concentrated at the toe of the slope. The location of the horizontal drainage pipes has significant impact of the global stability of the slope. The optimum length of the horizontal drainage pipe should be the horizontal projected length with a 10 degrees inclination angle. The double layered drainage system will result in a better solution.

Key words: Unsaturated Residual Soil, Precipitation, Seepage, Horizontal Drains