梯形渠道冻胀数值模拟与边坡系数优化

Numerical Simulation and Slope Coefficient Optimization of Frost Heave of Trapezoidal Channel

为了得到梯形衬砌渠道适宜的保温措施和渠道断面形式,采用考虑混凝土材料非线性特性及基土与衬砌间接触力学行为的梯形衬砌渠道冻胀破坏热力耦合数值模型的方法,以黑龙江蛤蟆通灌区总干渠为原型渠道,分析了3种不同保温措施对渠道冻胀量的影响,与不设置保温措施的对比段进行比较,并应用该模型分析了不同边坡系数对梯形渠道冻胀适应性能的影响。结果表明,综合考虑工程安全性与经济性,黑龙江省蛤蟆通灌区渠道最优保温板厚度为渠坡10 cm,渠底12 cm,与试验结果相一致;当梯形渠道保温板厚度取最优值时,梯形渠道最优边坡系数为2,此时渠道衬砌适应冻胀性能较好,工程造价也相对较低;研究结果可为黑龙江及其他北方地区梯形渠道提供参考。

A thermo-mechanical coupled numerical model was developed in this paper for trapezoidal lining canal considering the non-linear characteristic of soil freezing at the interface between the foundation and the concrete lining, as well as the plasticity of the concrete lining. We applied the model to the main canal in Hamatong Irrigation District in Heilongjiang Province in an attempt to help design the insulation measures and cross-sec- tions of the trapezoidal canal. Compared with canals without insulation measures, we analyzed the effectiveness of three insulation measures and different slope coefficient to the frost heave adaptability of the canal. The results showed that the optimal thickness of the canal insulation board in Hamatong Irrigation District was 10 cm on the slope and 12 cm on the bottom by considering engineering safety and economy, in close agreement with the experimental results. The reasonable slope coefficient of the trapezoidal canal was 2 while the properties adapt to frost heaving were better and the cost was relatively low in the situation. These results provide references and theoretical basis for trapezoidal canal design and operation in Heilongjiang Province and other similar areas.