Hydraulic Splitting Analysis And Three Dimensional Finite Element Analysis For Clay-Cored Earth Dam

Hydraulic splitting is one of the most concerned and controversial questions in the earth dam.Hydraulic splitting would cause destruction of the impervious material of the dam leading to the disastrous consequence.However, it is controversial that whether the impounded water pressure can create the crack on the surface of upstream wall to form the permeable joints causing the destruction of the dam in the project and the academic circles at present. There are some different views about terms and conditions,frequency,discrimination method of the hydraulic splitting.The possibility of the hydraulic splitting in the core dam is the key problem in the design of large dams.Therefore, It has the important theory value and the practical significance to design,construction procedure of the earth dams well as the dam body security by studying the hydraulic splitting, analyzing the terms and conditions as well as the mechanics, then presenting reasonable discrimination standard and the effctive precautionary measures.The article analyses and simulates the terms and conditions,the mechanics as well as discrimination standard.Firstly, the article sums up the available numeric method eg total stress method and effective stress method researching the hydraulic splitting based on terms and conditions as well as the mechanics, then generalizes the merits and demerits of the two method by comparing the calculation and obtains the limitation of effective stress method and the rationality of total stress method.At the same time, the total stress method is used to analysis the influencing factors causing the hydraulic splitting such as the elastic ratio,Poisson's ratio of the core and the dam shell material,dam slope,density of the core, and obtains that the elastic modular ratio of the core and the dam shell material and the Poisson's ratio of the core are the main factors comparing to the density of the dam shell and the core slope on the upstream.Secondly, the article further studies on the parameters eg elastic modular ratio of the core and the dam shell material and the Poisson's ratio of the core that more influencing the hydraulic splitting.By contrasting and analyzing two dam of different height and different slope, we can get the span of the elastic modular ratio of the core and the dam shell material and the Poisson's ratio of the core to control hydraulic splitting and distribute the reference for the design.Finally, we calculate the clay core dam of one hydroelectric station using the three-dimensional finite-element method.In the article, we intercept three representative sections and divine them separately to obtain that the hydraulic splitting will not take place in the hydroelectric station matching with the result about the span calculated though the parameters, at the same time, the precision of the span of the elastic modular ratio of the core and the dam shell material and the Poisson's ratio of the core has been proved.