| Our country has a vast territory and frozen soil area as well as widely distributed, because the engineering activities distributing in different geographical positions, so the engineering requirements are also different. Frozen soil can be used as engineering base for its rigid quality of a material in permafrost regions, so the project constructions are on the premise of protecting permafrost. While in seasonal frozen soil regions with the main objective of protecting the engineering structures for the harm of freezing – thawing cycles. In seasonal frozen area, active layer of frozen soil freezing in winter and thawing in summer, during the freezing-thawing process, the foundation will deform and make the structure demage. Heilongjiang province located in high latitudes zone, which is China’s important commodity grain production base, with a wide range of seasonal frozen soil and permafrost that make enormous influence on the running and development of the irrigation systems. The lining rate of canal slope are low and most of them are rigid lining. The temperature field and water field in the soil come up to uneven distribution under the action of freezing and thawing cycle and lead to the lining dislocation, sliding and collapse. The frost damage not only influences the canal proper functioning but also i ncreases the maintenance costs. Now the problem of freezing damage of hydraulic structure become the problem of farmland and irrigation construction. Therefore, how to protect the channels lining in deep seasonal frozen area from the cold damage is the key to promote the development of irrigation district.On the base of collecting and analysis of a large number of literature books, this paper analysed the mechanism of freezing damage of chanal lining, and with Beiyin project of Heilongjiang province for research background, combining the method of laboratory model experiments and field test to research freeze and heave with different lining structure types. Provides technical solutions of frost damage in lining works of the irrigated area of Heilongjiang province in distribution of frost heaving soil section., the research on the law of deep seasonal frozen soil’s slope’s freeze-thaw deformation caused by multiple freeze-thaw circles and the calculation formula of roughness with influence of freeze-thaw cycle, both of two have practical value and application prospect to prevent deformation of deep seasonal frozen soil slope. Main contents and conclusion were as follows:(1) In modle test the nature temperature processing was simulated, and the indoor test about Reno mattresses, concrete interlocking block and precast concrete board with insulation board were made. After the test obtain the conclusions about the frost-heaving mechanism of chanal lining and issue should be taken in field test.(2) According to the the conclusion of the lab test, the filed test project was set up at the section of stake mark 17+000~17+125 of Beiyin Wubei and the on-situ monitoring was made on the freeze-thaw deformations of three canal lining structures were on-site investigation, including Reno mattresses, concrete interlocking block and precast concrete board with insulation board. Measure their frost heave after a freeze-thaw cycle,come to the conclusion that: the deformation of soil of main canal is very unequally, and there has frost heaven soil and distributed non-uniformity clearly, as a result the flexible slope clining structure can suit for using in there. Because the concrete interlocking block and Reno mattresses can adapt the deformation. it is suitable for using in the main channel as slope clining structure. But the concrete interlocking block is cost more than the cost of laying of Reno mattresses. So there is recommending the Reno mattresses lining structure. |
PDF Full Text Request