格宾网箱覆绿功能反滤层优化设计研究

格宾网箱应用于边坡工程时具备护坡、覆绿及材料就地利用等多种特点。为了保证格宾网箱中的植被能够稳定存活,并且防止强降雨条件下植被土颗粒的流失,需对格宾网箱填充物进行反滤层的优化设计,从而实现绿色生态护坡的目的。依托北京冬奥会张家口赛区正在实施的“科技冬奥”项目,在模拟当地最大降雨强度条件下,采用自行设计的试验装置开展了反滤层的防冲刷试验,探究反滤层层数、厚度和反滤料粒径对反滤层防冲刷效果的影响,最终确定了格宾网箱覆绿功能反滤层的优化设计。试验结果表明：反滤层层数设置为两层,上下层厚度均为100 mm且上层碎石粒径小于20 mm、下层碎石粒径为20~100 mm时,反滤层的防冲刷效果最佳。

Optimal design of filter layers in Gabion mesh cages with landscaping function

The application of Gabion mesh cages in slope engineering can achieve multiple goals such as slope protection, landscaping and the utilization of local materials. In order to ensure the survival of vegetation in the Gabion cages and prevent the loss of vegetation soil particles under heavy rainfall, the inverted filter layers in Gabion cages should be optimized for the achievement of ecological slope protection. In order to explore the influence of the number of layers, thickness and particle size of the inverted filters on its anti-scour effect, an on-site anti-scour test of inverted filters was carried out with a self-designed test device under the condition of simulated local maximum rainfall based on the project of "Science and Technology of Winter Olympics" in Zhangjiakou division of Beijing Winter Olymic Games. Meanwhile, the optimal design of filter layers in Gabion cages with landscaping function was determined. The test results show that the anti-scour effect of the inverted filters is optimal when the number of layers is two, the thickness of both layers is 100 mm, the particle size of the upper layer is less than 20 mm and that of the lower layer is in the range of 20-100 mm.