季节性冻土地区渠道防渗防冻胀技术与应用模式

Techniques and Application Modes for Canal Seepage Control and Frost Heave Prevention in Seasonal Frozen Soil Area

在我国北方季节性冻土地区,混凝土衬砌防渗渠道的冻胀破坏比较广泛,对工程的危害程度最大。在灌区续建配套与节水改造中,目前常用的渠道防冻胀技术措施主要有保温措施、置换措施、隔水排水措施和结构措施等。根据北方16个大中型灌区调查资料,总结了不同条件下渠道防渗防冻胀技术的应用模式,认为在渠道防渗工程冻胀破坏严重的地区,应结合灌区的具体情况,采用防渗防冻胀复合结构形式,才能起到较好的防冻胀效果。

This paper analyzes the freezing types and damage forms in canal seepage control project and points out that the frost heave damage in concrete lining canal is extensive in seasonal frozen soil area of northern China; it is also the main freezing type and does the biggest harm to canal seepage control project; in the continuous equipping construction and water-saving reconstruction project of irrigation district, the common technical measures of canal seepage control mainly includes heat preservation measures, the replacement measures, water drainage measures and structural measures, etc. According to the investigation data of 16 northern large and medium size irrigation districts, the application modes of techniques for canal seepage control and frost heave prevention in different conditions are summarized in this paper. It is also pointed out that in irrigation district with serious frost heave damage in canal seepage control project, the composite structure mode combined with the actual situation should be adopted to obtain better prevention effect.