建筑废弃料对改良土壤蓄渗效果的试验及模拟研究

Experimental and simulated research on improvement of soil permeability using building waste materials

为了解决我国华南地区土壤质地黏重、渗透性能极差,无法及时排干随着不透水路面剧增而增长的城市径流雨水的问题,依据生物滞留池典型构造原理制备实验室自制滤柱装置,通过测试不同重现期下滤柱装置的下渗曲线,以评估不同粒径级配的建筑废弃料对土壤蓄渗的改良效果。结果表明:中小雨强下符合华南地区土壤特征和降雨条件的最优建筑废弃料粒径级配为5~9mm,且随着降雨重现期的增加,蓄渗改良效果更为明显,产渗流时间也显著提前;在SWMM中构建LID生物滞留池模块,根据试验结果进行模型率定,可为生物滞留池提供合理设定参数。研究成果拓展了建筑废弃料在低影响开发措施中的应用,以期为华南地区大规模海绵城市低影响开发措施的土壤蓄渗改造提供科学参考和评估工具。

In view of the poor textures and permeability of soils in South China,it is impossible to promptly drain the urban runoff rainwater that has grown with impervious pavement growth.A laboratory self-made filter column device was prepared based on a bioretention tank,the infiltration curve of the filter column device under different return periods was tested to evaluate the improvement effect of building waste materials with different particle size gradations on soil infiltration.The experimental results showed that the optimal particle sizes of building waste materials for the soil characteristics and rainfall conditions in south China is 5-9 mm,with the increase in the return period of rainfall,the effect of infiltration improvement is more obvious and the time for seepage is also significantly earlier.The LID bioretention tank module was constructed in SWMM and the model was calibrated based on the test results,the simulation provided reasonable parameters for the bio-retention tank.The research results have expanded the application of building waste materials in low-impact development measures and provided scientific reference and assessment tools for the large-scale sponge-city low-impact development measures for soil infiltration.