考虑含水条件的渠基土冻胀特性试验研究

Experimental study on frost heave characteristics of channel soil considering water content

水是促使土体发生冻胀破坏的关键因素,而渠道作为农业灌溉主要的输水载体,受季冻区环境威胁极易发生冻胀破坏。为了系统地研究水分对渠基土冻胀特性的影响,选取松干渠道典型土为研究对象,考虑不同的补水方式,探讨了不同含水率对渠基土冻胀特性的影响,给出了温度场、水分场和冻胀量的变化规律,对比分析两种补水方式的冻胀差异性,构建了关于含水率与补水方式的冻胀预测方程。结果表明:无论何种补水方式,冻胀量与初始含水率均成正比;同等条件下,开放系统的冻胀变形较封闭系统更明显,二者之间的比值为2~22,比值随着含水率的增大逐渐减小。研究成果可为渠基土冻胀防治提供参考。

Water is the critical factor to promote the occurrence of frost heaving,but as the main agricultural irrigation of water carrier,channel is easy to be destroyed by frost heaving threatened by the environment of seasonally frozen soil region.To study the influence of water on the frost heaving characteristics of channel foundation earth layer systematacially,this paper chooses the typical soil of Songgan channel as the object,considering the influence of replenishment methods,probing into the effect of different water content on characteristics of channel foundation earth layer so as to conclude the change rule of temperature field,moisture field,and frost-heave capacity.Comparing and analyzing the difference of frost heaving between the two replenishment methods,and then established the prediction equation of frost heaving about water content and replenishment methods.The results show that the frost heaving is in proportion to the initial water content under different replenishment methods.The frost heaving deformation of open system is more obvious than that of closed system under the same condition.The ratio of frost heaving deformation between open system and closed system ranges from 2 to 22 and the ratio decreases with the increase of water content.The results of this paper could provide a reference for the prevention of frost heaving disaster.