基于COMSOL Multiphysics的高陡岩质边坡复绿植生孔最优角度研究

Study on the Optimal Angle of Planting Holes for Regreening on High Steep Rocky Slopes Based on COMSOL Multiphysics

为研究植生孔最优角度的确定方法,提出了空间利用率、结构面揭露程度、接受水分补给能力、抗蒸发能力四项评价指标,综合运用三维建模、COMSOL多孔介质非饱和入渗模拟和热湿耦合水汽运移模拟等方法,探讨了植生孔角度变化对这四项指标的影响。为验证模拟结果,于徐州市园博园岩秀园宕口建立试验基地,长期监控、量测试验植生孔的各项参数指标,并进行了处理分析。结果表明,在控制孔深50 cm、孔径20 cm条件下,植生孔角度在40°~60°能保证较高的空间利用率;通过实测边坡及结构面产状建立对应三维模型并计算,可获取结构面揭露面积峰值对应的植生孔角度;在30°~80°,植生孔角度越大,越利于其接受自然降雨或喷淋养护等方式的水分补给,但同时使之在干旱条件下抗蒸发能力减弱。该研究结果和最优角度确定方法,对生产实践有良好的指导意义。

In order to develop a method of determining the optimal angle of planting holes on high steep slopes,four indicators of space utilization,degree of structural surface exposure,water recharge capacity,and anti-evaporation capacity were proposed to determine the optimal angle of planting holes for slope regreening,COMSOL Multiphysics was used to simulate the unsaturated infiltration of porous media and water vapor transport by heat and moisture coupling,and the influence of the change of the angle of planting holes on these four indicators was discussed.In order to verify the simulation results,an experimental site was established at the slope in Yanxiu Garden of Xuzhou Garden Expo Park,and the data of the test holes were monitored,measured and processed for analysis on site.The results show that under the condition of controlling depth of 50 cm and diameter of 20 cm,the planting hole angle of 40°~60°can ensure high space utilization;in the range of 30°~80°,the larger the angle of planting hole is,the better it is for receiving water recharge by natural rainfall or spraying maintenance,but at the same time,the resistance to evaporation under high temperature and dry conditions is weakened;the angle of the planting hole corresponding to best exposure of the structural surface can be obtained by establishing and calculating the 3D model of the slope and the structural surface.The research results and the optimal angle determination method have good guidance for regreening project.