Simulation Analysis of Seepage of Composite Geomembrane Anti-seepage Earth-rock Dam
Abstract: In order to evaluate the anti-seepage effect of composite purchase high quality HDPE liner anti-seepage earth-rock dam, a three-dimensional finite element model of the earth-rock dam is established by taking a composite textured geomembrane for sale earth-rock dam project of a reservoir, and the equivalent seepage coefficient of environmental geomembrane manufacturers is determined based on the analysis. Based on the value, the seepage simulation analysis of the composite high quality aquaculture geomembrane earth-rock dam was carried out. The calculation results show that the seepage flow of the composite textured geomembrane factory price anti-seepage earth-rock dam is 9.46×10-7m3/s·m, the seepage flow of the dam foundation is 1.71×10-4m3/s·m, and the seepage outlet ratio is decreased by 0.1224. 0.10 to 0.20. It is found that the composite high quality textured geomembrane has a good anti-seepage effect, and it is verified that the geotechnical dam adopts the rationality of composite low cost textured geomembrane anti-seepage, which can provide a reference for similar composite textured geomembrane factory price anti-seepage earth-rock dam project.
Keywords: anti-seepage textured geomembrane for sale; earth-rock dam; equivalent seepage coefficient; seepage simulation analysis
The composite purchase high quality HDPE liner has a small permeability coefficient and has the advantages of good anti-seepage effect, low price, and simple construction. However, due to human and environmental influences, the environmental geomembrane manufacturers will be damaged during the construction process, forming micropores, resulting in a large permeability coefficient and penetration mechanism. changes happened. Based on the above background, this paper studies the infiltration mechanism of composite high quality aquaculture geomembrane anti-seepage earth-rock dam, and uses the finite element software to calculate and evaluate the textured geomembrane for sale anti-seepage effect in a certain earth-rock dam, and draws relevant conclusions from the actual project.
1. Project Overview
A certain earth-rock dam is on the mainstream of the Yellow River. The dam top elevation is 139.0m, the maximum dam height is 20.2m, the dam crest width is 8.0m, the normal high water level is 134.0m, and the downstream waterless elevation is 119.7m. In order to achieve a good anti-seepage effect, the dam is laid with a composite purchase high quality HDPE liner with an area of up to 160,000 m2.
2. Finite element simulation analysis of earth-rock dam
2.1 Model establishment
The section of the dam channel section is selected for analysis. The design section of the channel section is: the dam body is combined with the intercepting cofferdam, and the foundation is built on the gravel foundation of the river channel. The upstream dam slope is 1:2.75, and the composite high quality aquaculture geomembrane inclined wall is used for seepage prevention. The composite high quality textured geomembrane is provided with a 0.15m thick medium sand cushion, a 0.20m thick gravel protective layer on the upper surface, and a 0.30m thick precast concrete block slope protection. The downstream dam slope is set at a height of 127.20m with a 3.50m wide horse track, the dam slope above the horse road is 1:2.25, and the dam slope below the horse road is 1:2.50. The slope is drained, and the concrete cutoff wall is connected with the composite environmental geomembrane manufacturers inclined wall to form Closed anti-seepage system. The concrete anti-seepage wall is 0.60m thick, and the bottom of the wall is embedded with 1.50m of bedrock.
Specific steps are as follows:
(1) Step 1: CAD modeling. Establish a CAD model of composite high quality aquaculture geomembrane anti-seepage earth-rock dam, save it as dxf format file, and import the file into finite element software. In the modeling, in order to facilitate the application of load in the finite element software, the Y coordinate of the composite purchase high quality HDPE liner anti-seepage earth dam body height is required.
(2) Step 2: Create a geometric surface. After importing the model, in order to facilitate the conversion from the X, Y plane to the Y and Z planes, the imported points are used to establish the geometric plane.
(3) Step 3: After the model is established, the material is assigned, the load is applied, and the boundary conditions are processed. In the seepage calculation, the required load is applied to the dam, and the interaction between the dam and the dam foundation is neglected, and the contact surface between the dam and the dam foundation is set as a three-way constraint.
(4) Step 4: Meshing. The finite element mesh obtained in this step plays a decisive role in the accuracy and economic analysis of the simulation results. There are two factors to consider when calculating. On the one hand, consider the cell shape of the mesh, the position of the intermediate nodes, the cell size, and so on. On the other hand, the meshing density should be considered. If the mesh is too large, the calculation result may be inaccurate; if the mesh is too small, the calculation may take too long and may even cause the computer to be inoperable. The three-dimensional model mesh of the composite purchase high quality HDPE liner anti-seepage earth-rock dam adopts a hexahedral and tetrahedral structured grid, which has a total of 7281 units and 8247 nodes. The model mesh is shown in Fig. 2.
(5) Step 5: Solve the calculation.
(6) Step 6: Analysis of the calculation results.
Fig. 2 Three-dimensional model meshing of earth-rock dam
2.2 Model related parameter data value
The model size is established according to the dam section of the river channel section. The upstream water level is 134m and the downstream water level is 120m. The value of the permeability coefficient of the composite high quality aquaculture geomembrane anti-seepage earth-rock dam and the allowable slope are shown in Table 1.
2.3 Simulation calculation results
After calculation, the total head cloud map, the total head contour map, the pressure head cloud map, the pressure head contour map and the free liquid surface (wetting surface) of the composite environmental geomembrane manufacturers anti-seepage earth-rock dam is obtained, as shown in Figures 3-8.
Figure 3 Earth dam total head
Figure 4 Total water head contour of earth and rock dam
Figure 5 Earthquake dam pressure head
Figure 6 Earth rock dam pressure head contour
Figure 7 Earth-rock pressure
Figure 8 Earth-rock dam free surface (wet surface)
It can be calculated from the calculation: the seepage flow of the composite textured geomembrane factory price anti-seepage earth-rock dam is 9.46×10-7m3/s·m, the seepage flow of the dam foundation is 1.71×10-4m3/s·m, the seepage outlet ratio is decreased by 0.1224, and the allowable ratio is reduced by 0.10～. 0.20. The dam of the composite low cost textured geomembrane anti-seepage earth-rock dam is basically in an unsaturated state, and the immersion line descends rapidly along with the environmental geomembrane manufacturers and is basically distributed along the riverbed of the foundation. The total seepage flow of the dam foundation is small, and the penetration ratio of the seepage outlet meets the requirements.
In addition, based on the approximate position of the immersion line, after statistical analysis, the measured values of each osmometer are significantly lower than the upstream water level, and the simulation results of seepage of the composite high quality textured geomembrane seepage earth dam are further verified. It shows that the dam with composite textured geomembrane for sale seepage prevention has good permeability.
(1) Relying on a composite textured geomembrane factory price inclined wall earth-rock dam project, the finite element analysis software is used to determine the value of the high quality textured geomembrane equivalent seepage coefficient by the fitting formula, and the simulation calculation analysis of the composite textured geomembrane for sale anti-seepage earth-rock dam is carried out. It is found that the composite low cost textured geomembrane has a good anti-seepage effect, improves the reservoir water storage capacity and the stability and safety of the earth-rock dam.
(2) Further research on the leakage of composite low cost textured geomembrane, study the relationship between the leakage of composite textured geomembrane factory price defects and related influencing factors, compare the results of seepage simulation of composite low cost textured geomembrane anti-seepage earth-rock dam, and establish a sound mechanism of composite high quality textured geomembrane infiltration.