Research On Anti-Seepage And Anti-Heave Material In Canal Seepage Control

The canal lining freeze damage prevention has become one of the pressing problems to be solved in production and practice in north drainage irrigation area. The rice husk has characteristics such as porosity, low density, low thermal conductivity, and so on. Mixing it in the concrete, on one hand may use the agriculturaloffal fully, recycle waste; on the other hand, can enhance the concretes heat preservation effect. this kind of new canal lining material has double functions of seepage, thermal insulation and anti-frost-heaving, and it has imprortant research value and the positive social meaning.This paper has determined the new canal lining material component based on the analysis on the achievement which the predecessor studied. Using methods of orthogonal test and variance analysis to make a study of the water ratio and rice husk amount to the effect on concrete project performance, such as compressive strength, elastic modulus, apparent density, permeability resistance, freezing resistance and thermal insulation performance, and so on. The main findings are as follows:(1)The water ratio and the rice husk amount and the correlation have a remarkable influence on compressive strength of concrete. Along with water ratio enlargement, the rice husk concrete intensity tendency reduces gradually. The compressive strength of rice husk concrete reduces along with the increase of rice husk amount. When the rice husk amount is bigger than 12%, compressive strength of rice husk concretes is smaller than 10MPa, which is lower than the code requirement. Therefore ,the rice husk amount should not be smaller than 12%. When the water ratio is 0.4, the rice husk amount is 6% , the compressive strength of concrete is maximum.(2) The elastic modulus of rice husk concrete reduces along with the rice husk amount increase, and increases first and then lower along with water ratio increase. It is known through analysis on two element chart, the superior matching of elastic modulus of rice husk concrete is the water ratio 0.4, the rice husk amount 12%.(3) The rice husk amount have an extremely remarkable influence on the apparent density of concrete, but the influence of correlation of water ratio and rice husk amount is small, and it can be neglected. The apparent density of rice husk concrete reduces along with the amount of rice husk increase. When the water ratio is 0.4, the rice husk amount is 12%, the apparent density of rice husk concrete is the smallest. (4)The relative permeability coefficient of concrete increases gradually , along with rice husk amount and water ratio increase. Strength loss rate of rice husk concrete increases gradually along with the increase of rice husk amount and water ratio. This indicated that water ratio of rice husk concrete is not suitable oversized, and should control below 0.45.(5) After mixing in the rice husk, the thermal conductivity of concrete reduces large scale, and is about 14%~20% of common concrete thermal conductivity. When the water ratio is smaller than 0.55, the rice husk amount have a great effect on thermal conductivity of concrete. The thermal conductivity of concrete reduces along with the rice husk amount increases. When the water ratio is 0.55, the influence of the rice husk amount is very small ,and when the rice husk amount change from 9% to 10.5%, the thermal conductivity maintains invariable nearly. When the water ratio is 0.5, and the rice husk amount is 10.5%, the thermal conductivity of rice husk concrete achieves minimum value 0.2452 W/m·K. The heat preservation computation indicates that the rice husk concretes can solve the problem of frost heave damage of lining canal in micro-cold area such as Guanzhong area in Shaanxi.