季冻区矩型渠冻胀数值模拟及试验研究

Numerical simulation and experimental study on frost heave of rectangular canal in a seasonally frozen region

传统的U型渠混凝土强度较低,抗冻胀性较差,在寒区使用各方面指标难以达到正常运行要求,因此提出新型矩型渠。采用聚苯乙烯泡沫(EPS)颗粒轻质土垫层作为矩型渠的保温材料,对比不同掺量EPS颗粒轻质土对矩型渠的保温效果,结合数值模拟和物理试验模型,分析土体的冻结融化规律及冻融循环后的残余变形量。研究结果表明:土体冻结是单向冻结、双向融化的过程,且土体的最大冻深发生在温度上升段0℃附近;EPS颗粒轻质土垫层对矩型渠土体起到很好的保温作用,EPS颗粒轻质土掺量越高,土体冻胀量和冻深的削减量也越大。

The strength and frost resistance of traditional U type concrete canal is poor.It is difficult to achieve normal operation in the use of the indicators in the cold area,so we put forward a new type of rectangular canal.Using expanded polystyrene(EPS)grain light soil cushion as the insulation material of rectangular channel,the insulation effect of rectangular channel using different amount of EPS grain light soil was compared.Combined with numerical simulation and physical test model,the freezing law of soil and the residual deformation after freeze-thaw cycle were analyzed.The results show that:the process of soil freezing is unidirectional and two-way melting,in which the maximum frozen depth is in the soil temperature rise near 0℃.EPS particle light soil cushion to insulation has a good effect on rectangular canal soil.The higher the light soil EPS particle content,the greater the amount of frost heave and frost depth reduction.