Stress And Strain Analysis Of Composite Geomembraae Of The Whole Bottom Seepage Prevention Of Piedmont Sloping Plain

Most of the rivers originated from mountain area in Xinjiang, the river is short and the longitudinalslope is large, reservoir construction is often lack of suitable terrain and geological conditions. Theconstruction of plain reservoirs would cause soil salinization at downstream, and due to the bottom ofreservoir is large, water loss is serious, it will have an impact on the stability of dam foundation at the sametime. Building regulating reservoir is one of the most important measures to increase water use efficiencyin the piedmont sloping plain of the mountain pass. The piedmont sloping plain in the mountain passbelong to the large cover thickness of gravel and the vertical seepage area which is the permeability isstrong, so seepage treatment of the reservoir bottom become the key technology of the building reservoirs.With the development and advancements of industry, industry provide composite geomembran materialwith seepage prevention is good and very economy, it makes seepage prevention of all the bottom becometrue and gives technical guarantee for reservoir construction of in arid regions.In the past, selecting composite geomembran is mostly based on experience, or based on the curveintersection method of membrane theory of Professor Gu ganchen to determine the film thickness. Thetraditional view that the geomembrane paved on the surface of the reservoir bottom, affected by the damand water load force, it will produces dependent deformation by the deformation of the bottom, thedisplacement results of each point of composite geomembran is equal to the corresponding displacement ofthe bottom surface. Therefore, we can use “Standard for application of geosynthetics in hydraulic andhydro-power engineering” to evaluate the safety of material by stress or deformation conditions, thismethod is called “specification method”.With the development of the technology and theory of finite element software, the membrane elementcan be used to simulate stress-strain characteristics, using a unified stress field or displacement field to fullyreflect the interactions among the dam, dam foundation, the bottom and the composite geomembrane, toevaluate the safety of geomembrane seepage prevention. In the past it is few to research, this articlecombined the experiment and the practical engineering, using the finite element to analyze compositegeomembrane of all bottom seepage prevention, gaining work attributes of stress deformation, provide anew way of safety evaluation which is shorted finite element method.The research shows that the stress-stain distribution and extremum of completion and full storageperiod of the reservoir seepage system all in a reasonable range, ensuring the safe operation of dam. And italso can help to offer the reference for the engineering design and a set of effectual safety assessmentmethods.