降雨条件下不同类型植被边坡稳定性的研究

降雨对植被边坡稳定性的影响是目前生态护坡领域研究的热门话题。基于MIDAS GTS/NX，结合张家口地区某边坡工程背景并选取当地常见的护坡植被，针对裸露边坡、高羊茅（Festuca arundinacea）植被边坡、小叶黄杨(Buxus microphylla)植被边坡以及高羊茅-小叶黄杨混合植被边坡四种工况，对降雨条件下边坡内部土体孔隙水压力随时间的变化以及边坡稳定性的大小进行对比分析研究。结果表明：（1）在相同的降雨强度和降雨时长条件下，三种植被边坡的入渗速率均小于裸露边坡，植被边坡相对于裸露边坡有着更好的持水能力。在四种不同类型的植被边坡中，高羊茅植被边坡孔隙水压力增幅最小，位于坡顶、坡面、坡底的土体仍然维持了部分基质吸力，高羊茅植被减小了降雨的影响深度。（2）降雨结束后，高羊茅植被边坡较其他植被边坡安全系数最大，高羊茅植被增加了边坡土体的有效应力，更能有效地提升边坡的稳定性。上述研究旨在为降雨对植被边坡的影响提供参考，为半干旱地区的植被护坡技术提供指导。

Study on the Stability of Slope with Different Vegetation Types under Rainfall Conditions

The influence of rainfall on the stability of vegetation slope is a hot topic in ecological slope protection. Based on MIDAS GTS/NX, and combined with the background of a slope engineering in Zhangjiakou area, common local slope protection vegetation has been selected. Slopes incloude four working conditions: Bare slopes, Festuca arundinacea vegetation slope, Buxus microphylla vegetation slope and Festuca arundinacea-Buxus microphylla mixed vegetation slope. The variation of pore water pressure with time and slope stability under rainfall condition are compared and analyzed in this article. The results show that :(1) Under the same intensity and duration of rainfall, the infiltration rates of the three vegetation slopes were lower than that of the exposed slope. Compared with the bare slope, vegetation slope has had better water-holding capacity.Among four different types of vegetation slopes, the increase of pore water pressure in Festuca arundinacea vegetation slope is the least .The soil located in the top, surface and bottom of the slope has still remained a part of matron suction.Festucaarundinacea has reduced the influence depth of rainfall. (2) After the rainfall, the Festuca arundinacea vegetation slope has had the highest safety factor compared with other vegetation slopes. Festuca arundinacea has increased the effective stress of slope soil and improved the stability of slope effectively. The above research has aimed to provide reference for the influence of rainfall on vegetation slope and guidance for vegetation slope protection technology in semi-arid areas.