The Standardized Technology Mode Of Canal Seepage Control And Replacement Frost Heave Prevention

Frost heave damage is a key constraint factor for the concrete lined canal construction in the northern cold regions of China. China is a large agricultural country, adopting canal to transfer water for irrigation is one of the main ways of agricultural irrigation. Meanwhile, because our country is short of water resources, it is irreplaceable and significance to develop canal seepage control technology for the long-terms development of China’s agricultural water-saving irrigation projects. The paper based on analyses the studies and applications of canal seepage control and replacement frost heave prevention technology, systematically summed up the frost heave damage factors of concrete lined canal. by analyzing the research data and the test results of the canal seepage control & replacement frost heave prevention, the paper proposes a standardized structure pattern of the replacement frost heave prevention technology for the concrete lined canal, gives its conditions and scopes and confirms the technical requirements of the replacement layer construction. And based on the thermal resistance equivalence principle & take into the canal "allow to reserve a certain amount of frost heave" account, this paper establishes the calculation formula of replacement layer thickness,and use the test canal results analyzed and verified the formula. The main results are as follows:Firstly, by systematically analyzes and summarizes the seasonal frozen soil area canals failure mechanisms and failure characteristics, and rely on the of the actual application of current canal seepage control and replacement frost heave prevention technology, the paper proposes a standardized structure pattern of the replacement frost heave prevention technology for the concrete lined canal, gives its conditions and scopes, confirms the technical requirements of the replacement layer construction, establishes the calculation formula of replacement layer thickness, forms the standardized mode of seepage control and replacement frost heave prevention for concrete lined canal.Secondly, analyzes the test canal results of Xinjiang Chonghuer irrigation district, which indicates that by seepage control and replacement frost heave prevention for concrete lined canal can prevent the occurrence of canal frost heave effectively, the best replacement depth of the test canal is 50 cm at the top of canal, 60 cm at the central of canal slope, and 70 cm at the bottom of the canal slope and the bottom of canal. The frost heave amounts of canal are in the range of regulatory requirements, meeting the needs of practical canal project seepage control and frost heave prevention.Thirdly, according to the standardized structure pattern of the seepage control and replacement frost heave prevention for the concrete lined canal, this paper based on the thermal resistance equivalence principle & take into the concrete lined canal "allow to reserve a certain amount of frost heave" account, this paper establishes the calculation formula of replacement layer thickness,and combined with the test canals data, introduces and ensures the correction coefficient K. Through the test results verified the accuracy of the calculation formula of replacement layer thickness, the results indicate that the maximum error between the paper calculate values and the best values of test canal is only 4%, it indicates that the paper formula has a high accuracy to meet the needs of the canal replacement frost heave prevention project, can play a reference role for the design of canal seepage control and replacement frost heave prevention project.