季节冻土区光伏支架螺旋桩基的冻胀数值分析研究

利用有限元软件COMSOL自定义模块功能，将建立的水热力三场顺序耦合模型导入，模拟二维轴对称条件下多种螺旋桩在土体冻结过程中发生的冻拔，并设置光滑桩作对比.在冻深达到桩长全长时，全螺旋小叶片桩具有良好的抗冻拔效果（仅为光滑桩的19.5%）.使用COMSOL内嵌热应力模块，模拟三维条件下螺旋桩抗冻拔过程，并与室内试验结果作对比.结果显示冻深只有桩长一半时，双螺旋小叶片桩明显减少桩体冻拔量.表明：通过数值分析可比选出抗冻拔的最优桩型，对于现场试验的光伏支架螺旋桩型设计提供参考.

Numerical simulation on anti-jacking-up performance of helical piles of photovoltaic stents in seasonal frozen region

Based on custom module of COMSOL,by introducing moisture-heat-stress sequential coupling model established,the jacking-up process of different helical piles under two-dimensional axisymmetric condition is simulated with using smooth pile for contrast.When the frost depth reaches full length of the pile,small-blade helicaled pile performs well in anti-jacking-up (19.5% of that of smooth pile).The embedded thermal stress module is used to simulate the anti-jacking-up process of helical pile under three-dimensional condition,the result of which is compared with laboratory test.The outcome shows that the jacking-up displacement of helical pile with two small blades is the least when the frost depth reaches half the length of the pile.It indicates:the optimal type is picked through numerical simulation,which can provide a reference to the design of helical pile of photo-voltaic stents in field test.