摘要: |
为筛选适合河套灌区排水暗管的外包料,利用自制水力渗透仪,将2种类型的土工布(68g/m2和90g/m2)与5种不同粒径的砂滤料组合,开展室内土柱试验,研究暗管排水条件下土工布单一防护及土工布与不同粒径砂滤料相组合防护措施对外包料渗透系数、土壤流失量及淤堵率的影响。结果表明,B4处理稳定后的渗透系数(0.428×10-2cm/s)是B1的2倍,且渗透系数显著高于B10,加设砂滤料能显著提高外包料渗透系数(P<0.05);B4系统稳定后的渗透系数为0.052×10-2cm/s,较B6的渗透系数提高了5.8%,加设砂滤料能显著提高系统渗透系数并且能与其外包料的渗透系数保持在相对稳定的状态;B4处理的土壤流失量为0.65g,流失量较少,可以忽略不计,加设砂滤料对防止土壤流失的效果不显著;土工布加设砂滤料的形式能显著降低淤堵率(P<0.05),但B4的淤堵率为26%,较B1~B6处理的淤堵率平均减少了26%,其防淤堵效果最佳。B4处理综合效果较佳,能显著提高外包料和排水系统整体的渗透系数,有效降低外包料的淤堵率,并且能维持土壤稳定。综上,河套灌区排水暗管适宜的外包料建议选用68g/m2土工布与最大粒径为1 mm砂滤料组合,研究结果可为河套灌区下游排水暗管外包料的选用提供理论依据。 |
关键词: 排水暗管;土工布;砂滤料;筛选;河套灌区 |
DOI: |
分类号:S278 |
基金项目:内蒙古科技重大专项(zdzx2018059);内蒙古自治区科技计划项目(201802065) |
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Experimental Research on Outer Material Screening of Drainage Underground Pipeline in Hetao Irrigation District of Inner Mongolia |
hulingling, Yang Shuqing
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Inner Mongolia Agricultural University
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Abstract: |
In order to select the outer material suitable for the drainage concealed pipes of the Hetao irrigation area, using a self-made hydraulic permeability instrument, two types of geotextiles (68g/m2 and 90g/m2) are combined with 5 types of sand filters with different particle sizes to develop indoor soil columns. Experiments to study the effects of single geotextile protection and geotextile combined with sand filter materials of different sizes on the permeability coefficient, soil loss and siltation rate of the outer material under the condition of concealed drainage. The results show that the permeability coefficient after stable treatment with B3 is 0.496×10-2cm/s, which is 2.27 times the permeability coefficient of B1, and the permeability coefficient is significantly higher than that of B9 (0.258×10-2cm/s). Significantly increase the permeability coefficient of the outer material (P<0.05); the permeability coefficient of the B2 treatment system after being stabilized is only 35% less than the initial permeability coefficient of the outer material, and the permeability coefficient of the B4 system after being stabilized is 0.052×10-2cm/s, which is The permeability coefficient of the outsourcing material is 13%, which can be kept in a relatively stable state with the permeability coefficient of the outsourcing material; the soil loss of the B5 treatment is 0.67g, which is small and can be ignored. The addition of sand filter material can prevent soil loss The effect is not significant; the form of adding sand filter to the geotextile can significantly reduce the clogging rate (P<0.05), but the clogging rate of B12 is 1% higher than that of B7, and the clogging rate of B4 treatment is 26%. B1 treats 55% of the blocking rate, and its anti-blocking effect is the best. The overall effect of B4 treatment is better, it can significantly increase the overall permeability coefficient of the outsourcing material and the drainage system, effectively reduce the clogging rate of the outsourcing material, and can maintain soil stability. In summary, it is suggested that 68g/m2 geotextile and sand filter material with a maximum particle size of 1 mm should be selected as the suitable outer material for drainage concealed pipes in Hetao Irrigation District. The research results can provide a theoretical basis for the selection of outer drainage concealed pipes in Hetao irrigation area. |
Key words: Subsurface Drainage;Geotextile; Sand filter; Screening;Hetao Irrigation District |