Study On Application Of Clay Cement Slurry In Anti-Seepage Curtain In Karst Dam Area

The Karst landforms are widely distributed in Yunnan,China.The water conservancy engineering and water resources utilization are seriously affected,because of the karst springs,dissolved karst caves and dissolution cracks in the dissolved rocks.The seepage prevention and plugging project is particularly important.Anti-seepage reinforcement effect of anti-seepage curtain is the best in grouting technology.For the grouting project,the major technical indicators affect the safety of the project is the performance of clay-cement slurry,and the project cost is equally important as an economic problem.In this paper,through a series of indoor experiment,The effects of different cement and quick-setting admixture on the performance of clay-cement slurry were studied.The viscosity of the paste was controlled between 25-30s after the modification.The cement content was 5,10,15g/100ml puree,The coagulant dosage level is 1,3,6g/100ml puree.The results show that the rate of water addition increases with the increase of cement content,the slurry stability decreases,and the effect of the quick setting admixture on the rate of slurry water is not significant.In the experiment,the rate of slurry water in each group is less than 5%for the stability of slurry;slurry gelation time with the quick-setting agent dosage changes from a few minutes to a few seconds adjustable,the amount of quick-setting agent for the 3g/100ml puree,the clay cement slurry gel time is shortest only 7s;The stone rate of slurry increased with the increase of the quick-setting admixture,and the swelling phenomenon occurred when the 6g/100ml puree was used.The more the cement content was,the more obvious the shrinkage of the slurry stone body.The permeability coefficient of the cement slurry decreased with the cement content increasing.The results show that the early strength of slurry stone is slow,and the growth rate is quick in the later period,and the minimum in the third day,the third day,the second day and the third day.Strength of 0.13MPa,the maximum strength of 28 days 3.35MPa,the test group slurry stone body compressive strength of grouting material requirements are reached.Combined with a reservoir reinforcement project in Shilin County,Kunming,Yunnan Province,obtained the most superior allocated proportion through the indoor experiment:red-clay mud funnel viscosity between 25s to 30s,the cement content was 15g/100ml puree,the coagulant dosage level is 6g/100ml puree.Based on the finite difference software FLAC3D,the numerical model is used to analysis and calculation the stress characteristics and displacement characteristics of the dam under the normal water level about the natural conditions and the treatment conditions,project in Shilin County,Kunming,Yunnan Province.The results show that with the red-clay cement slurry for curtain grouting,the stress of the anti-seepage treatment site are within the allowable range of the material and effect is well,which meets the safety requirements of the engineering.