| The water conveyance channel in northern Xinjiang is a seasonal water conveyance structure in cold regions.It has been operating for nearly 20 years,and problems affecting the safe operation have occurred to varying degrees,such as concrete cracks,uplift pressure damage,erosion,freeze-thaw,lining plate surface uplift,and slab joint mortar carbonization.The water conveyance loss of the channel has increased.The reason for this is that the leakage during the operation period causes a high groundwater level,leading to severe damage to the uplift pressure and frost heave of the lining composite anti-seepage layer during the winter water outage period,and the leakage amount of the channel increases year by year.Channel leakage has become a common problem in water transmission engineering.Leakage not only affects the efficiency of water transmission,but also poses a huge threat to the stability of channel slopes,restricting the effectiveness of channel engineering.To solve the above problems economically and effectively,a channel anti-seepage treatment approach is proposed by applying new anti-seepage materials to the surface of the original channel lining without replacing the composite lining anti-seepage layer on a large scale.However,as a new material,the surface flexible coating is applied to the anti-seepage reinforcement of water conveyance channels,and the comprehensive evaluation of its actual anti-seepage effect lacks theoretical basis.In order to verify its actual effect,relying on the water conveyance channel project in North Xinjiang,the anti-seepage reinforcement effect of the surface flexible coating is evaluated around the material performance,construction methods and defects,on-site effect and existing problems,anti-seepage effectiveness analysis,anti-seepage safety analysis of the surface flexible coating anti-seepage repair technology,so as to form a systematic technical application study.The research content and achievements of this article are as follows:(1)Conducted research on surface flexible coating anti-seepage technology,introduced the performance and practical engineering application of polymer cement waterproof coating,and elaborated on its film-forming mechanism and waterproof mechanism;By conducting impermeability tests,the effects of factors such as application method,reinforced fabric,polymer cement ratio,and operating conditions on the impermeability of the sample were explored;We studied the anti-seepage and bonding properties of the interface between antiseepage coatings,concrete,and mortar.Based on the results of the anti-seepage performance test,we optimized the construction process of polyacrylic acid polymer anti-seepage coatings,in order to provide a basis for channel leakage repair and anti-seepage reinforcement.(2)Conducted research on surface flexible coating anti-seepage technology,introduced the performance of polymer cement waterproof coating,and elaborated on its film-forming mechanism and waterproof mechanism;Through impermeability tests,the effects of factors such as application method,reinforced fabric,polymer cement ratio,and operating conditions on the impermeability of the sample were explored.The impermeability and bonding properties of the impermeable coating at the interface between concrete and mortar were studied;Based on the experimental results,the construction process of acrylic polymer waterproof coating for channels is proposed,in order to provide a basis for the repair of channel leakage and anti-seepage reinforcement.(3)We conducted a safety analysis of surface flexible anti-seepage technology,established a coupling model of water and heat,calculated and analyzed the changes in temperature field,water distribution field,deformation and stress field before and after channel anti-seepage reinforcement.We also calculated and analyzed the stability of the channel slope under the complete cycle,and evaluated the safety of its anti-seepage reinforcement effect.(4)Finally,the field application research of the surface flexible coating was carried out,and the prototype monitoring method was used to establish an automatic monitoring platform.Through the monitoring data,the seepage characteristics and distribution laws of the water conveyance channel in North Xinjiang before and after the surface flexible coating was used for seepage prevention and reinforcement were analyzed in depth,and the seepage prevention effect of the surface flexible coating was evaluated.The results showed that its seepage prevention effect was significant.The above research indicates that the surface flexible coating can significantly reduce the pore water pressure of the channel foundation,maintain relatively stable seepage of the channel,and significantly improve the anti-seepage and frost heave resistance of the channel.The research results of this article can provide a basis for channel leakage repair and antiseepage reinforcement,and have certain scientific significance and practical value for channel engineering construction and governance. |
