The Safty Analysis Of Concrete Diaphragm Wall Of The Three Gorges's Second Stage Coffer Dim

Concrete diaphragm wall is one type of underground continuous wall, which is adopted extensively in depending seepage for water conservancy and reservoir. Underground continuous wall is a construction method which has a short history .At present, the tradition design method for concrete diaphragm wall is dominating. According to the documentation collected from domestic and abroad Wang wei dong who works in Huadong architect and structure institute utilizes the similar work property between the underground continuous wall and pile subjected the vertical loads, and introduces Poulos method of elasticity and plastic which applies to pile foundation into the calculation for subsidence of underground continuous wall. Pujialiu and Yu Yuzhou from water and electronic engineering of Qinghua university, according to the result of three axes, define the concrete parameter utilize the model of non-linear E-B combined with the design cross section of dam in Xiaolangdi, yellow river accept the total stress programme of THEPD dam, and we analyze the stress and displacement of plastic concrete diaphragm wall by Finite Element Method in comparison with the result of common concrete one. At same time, we consider the effect of the character of plastic concrete diaphragm wall which is composed of different gradients and adopting the level of stress and pulling stress infers whether the plastic concrete diaphragm wall is safe or not. Right now, the main means to do security analyzing of concrete diaphragm wall is concrete character experiments indoors and survey on the spot. Security analyzing can't do without calculating, supervising and forecasting. Calculating adopts the way of finite unit spot parameter by using the character of dispersion. Thus, it can get the similar answer of stress, stress strain and displacement. Supervising uses strainmeters, non-stressmeters and tiltmeters, which are buried in the concrete wall to supervise the stress, tress strain, displacement during period of working and makes the forecast.This paper analyzes and explores stress strain model and principle of the project of concrete diaphragm wall after concluding other engineers and project practices and describing the seepage and deformation character of the plastic concrete used in the cofferdam of the second stage of the Three Gorges Project. We analyze and forecast the change trend by using mathematics statistics regression ,then we get the best regression equation. Finished it, we used this way to the cofferdam of the second stage of the Three Gorges Project .It proves that the method which I have introduce in this article is effective for the stability of concrete diaphragm wall and it is also a valid for supervising cofferdam security after using it in many projects.