The Research On Seepage Control And Drainage Measures In Foundation Of The Concrete Gravity Dam Based On The Finite Volume Method

Concrete gravity dam which maintains stability depending on its own gravity is a kind of classical and practical dam type. The difference from other buildings is that, its construction not only considers the general problems (such as: foundation strength, deformation) but also considers the problem of water leakage to complete the key links of the leakage of water seepage control. According to statistics work of dam construction, seepage and drainage are two mostly effective methods used in the leakage problems of Dam foundation, which is consistent with the basic principles in the seepage control of"plugging in the front and draining on the back". So seepage prevention curtain and drainage holes are the indispensable combination in the foundation seepage control measures.There are many physical parameters on seepage prevention curtain and drainage holes, and most of them are chosen based on geological, hydrogeological and engineering geological conditions, or chosen combined with empirical formulas and referenced existing engineering example. This method normally can satisfy engineering requirements for the middle and low dams which own simple hydrogeological, engineering geological conditions, but when it refers to the dams with taller height, more complex geological conditions, higher safety level, we cannot simply depend on experience coefficient any more. Many domestic and international experts on seepage control using analysis, experiment and electricity simulation method to study the influence of curtain and drainage holes'physical parameters on seepage field, but little relevant study on seepage analysis is carried out through the method of numerical simulation program predictions based on the finite volume method.This paper studis the flowing law of fluid in dam foundation porous media useing Fluent software in computational fluid dynamics, seeks the influence law of the physical parameters of seepage prevention curtain and drainage holes on dam foundation seepage field, introduces the finite volume method based on the theory of seepage, and then raises the numerical simulation program– Fluent, which is mostly used in computational fluid dynamics. After introducing the program briefly, numerical simulation which is based on the semi-infinite deep simple seepage field of underground contour line is seemed as an example. The accuracy of the Fluent procedure in porous media module calculation of dam foundation seepage field is investigated by comparation between analytical solution obtained by the theoretical analysis and Fluent soft numerical simulation program, then it is proved that Fluent soft numerical simulation program can meet the engineering requirements. In order to explore the influence of the various physical factors of the seepage prevention curtain and drainage holes on the dam foundation seepage field, and to find a reasonable seepage controlling strategy of plugging in the front and draining on the back, three situations are mainly analied: there is only the seepage prevention curtain with the single factor function, only drainage holes of single factor role, the two factors work together under the depth factors mutual collocation seepage field carried on the detailed numerical simulation. The numerical simulation result is outputted, analyzed and compared by post-processing software. After that, this paper finds out the law between seepage flow and uplift pressure in dam foundation according to different types of dam foundation when the depth, thickness, position of curtain, depth, diameter, and pitch of drainage holes are changed, this paper also finds out the low of seepage flow and uplift pressure space in dam foundation when depth collocation between seepage prevention curtain and drainage holes is different. Besides, the reasonable measures for anti-seepage and drainage are puted foward in this paper according to different types of geological and engineering requirement.