Study Of Different Aggregate Construction Technology On Effect Of Water Permeability Of No Sand Concrete Slab

No sand concrete slab seepage water as a water abstraction technology, it was put forward by combining river water diversion with groundwater development. It could meet the demand of a certain amount of water by using water abstraction technology, and could have a certain degree of filtering effect of water resources.In actual engineering, most of the seepage water was not through the single medium which made up of no sand concrete slab, but through the permeable layer which made up of a variety of medium for water. It proved for a long time of engineering practice and experiment, through the internal pore and fracture of concrete slab the extraneous water even the silt-laden flow would enter into the interior of the concrete slab or deposit on the concrete slab in the way of diffusion and penetration,leading to the permeability degradation of the concrete slab, and then had a serious impact on seepage water efficiency and durability of the concrete slab,the topic took it as a starting point,to study three different particle sizes of aggregate and different the laid order of aggregate on the influence water permeability of no sand concrete slab.Based on the actual project in Shanxi Province, "XinAnquan water abstraction engineering " as the subject source, through the research method of combining experiment with numerical simulation, focusing on the working head,the particle size and laid order of aggregate and so on,in order to study the seepage law of porous media which composed of no sand concrete slab and aggregate,and different aggregate construction technology on effect of water permeability of no sand concrete slab,through the research,the following conclusions had been drawn:(1)Analyzed the correlationship between the density of no sand concrete slab, working head and seepage discharge of no sand concrete slab.It was shown that The larger the size of aggregate,the less the effect of seepage on the no sand concrete slab. But the larger density,the smaller the seepage discharge of no sand concrete slab.(2) Analyzed the effect of the single aggregate,two kinds of aggregate and three kinds of aggregate on the water permeability of sand free concrete slab.It was shown that The larger the size of aggregate,the less effect on the seepage of the sand free concrete slab.For the same piece of no sand concrete slab,the order of aggregate had an influence on the seepage efficiency of no sand concrete slab.The influence was the greater the particle size of aggregate along the direction of the water flow,the less the effect of the seepage on no sand concrete slab.(3)The seepage characteristics of the water flow were all the transitionzone of laminar flow to turbulent flow under all operating conditions in this study. And by data fitting,got the relationship of the per day seepage catchment flow of no sand concrete slab and working head under all operating conditions.(4)By using dimensional method,established the seepage flow equation of the seepage flow system composed of no sand concrete slab and aggregate.(5)By using R language,analyzed the correlationship between the seepage flow, the density of no sand concrete slab,the working head,the size of aggregate and the laid order of aggregate.And by the multiple regression analysis,analyze the density,the working head and the particle size of aggregate which has influence on the water permeability of no sand concrete slab.It was shown that the density of no sand concrete slab has the greatest influence on the seepage flow,followed by the particle size of aggregate, and finally the working head.(6)By using porous medium model of the Fluent,carry out the numerical simulation for the seepage of the seepage flow system composed with no sand concrete slab and aggregate.This model also had a study of pressure variation of flow in the seepage flow system.The numerical simulation results and physical model test results were compared and analyzed,it was shown that its maximum error was 4.87%, and the minimum error was 0.58%.The research results of this literature provided a theoretical basis for the taking water of the seepage of aggregate and no sand concrete slab,meanwhile had a certain reference value of how to lay aggregate on no sand concrete slab to reach the design needs of the flow in the real hydraulic engineering.