株下竖向植筋带联合植被护坡的水力特性土柱试验

Test on Hydraulic Characteristics of Vegetated Soil Column with Vertical Geotextile Belts

为探究竖向植筋带联合植株的护坡水力特性,设计开展了一维土柱试验,在干湿循环条件下,观测了坡土表面裂隙的发育情况,监测了坡土内部体积含水率和吸力等水力特性的变化规律。试验发现:在干燥过程中,蒸发蒸腾作用会促进土体表面裂隙的发育,裂隙的深度与宽度随干湿循环次数的增加而增加,联合植筋带后蒸发蒸腾引起的吸力增量大于仅由植物边坡蒸发蒸腾产生的吸力增量;在降雨作用下,植筋带也会成为明显的优势流入渗通道加速雨水入渗,致使土体产生更多的吸力损失值。因此,必须设法把植筋带顶部及其周围的土体压实,减少坡土开裂,避免在降雨工况下顺着植筋带的优势流入渗,充分发挥竖向植筋带作为延长根的加筋作用。

In order to explore the hydraulic characteristics of soil slope installed with vertical geotextile belts and plants,one-dimensional soil column test was designed and carried out.Under the condition of drying-wetting cycle,the development of surface cracks in the slope soil was observed,and the hydraulic characteristics such as volume moisture content and suction of slope soil were monitored.It is found that in the process of drying,evapotranspiration can promote the development of cracks on the surface of soil,and the depth and width of cracks increase with the number of drying and wetting cycles.The suction increment caused by evapotranspiration of the vegetated slope model with vertical geotextile belts is greater than that of the vegetated slope.It seems that under rainfall the vertical geotextile belts may become the obvious inflow channels and lead to more suction loss.Therefore,it is necessary to compact the surface slope soil around the vertical geotextile belts,so as to reduce the infiltration along the vertical geotextile belts under rainfall,and make sure that the vertical geotextile belts play as a role of the extended root.