Analysis On Stress And Strain Of Deep-thick Overburden Layer Concrete Face Rock-fill Dam

Concrete rock-fill dam is widely used in engineering because of its wide adaptability,high security and better economy. With the widespread use of concrete rock-fill dam, the damon deep-thick overburden layer has become very common, so the research of stress and strainfor concrete face rock-fill dam on the deep-thick overburden layer studies is particularlyimportant.The overall development process of rock-fill dam is introduced in this paper, based onthe characteristics of dam on the deep-thick overburden layer, the impact of deep overburdendam to the stress and deformation is researched taking the Cha ha wu su rock-fill dam as anexample. By comparing advantage of the constitutive model,the Duncan Chang E-B model isused in analysis due to its clear physical meaning and better fitting of measuring curve, and itis introduced detail in the paper.The three-dimensional finite element model is established of Cha ha wu su rock-fill damin this article, using the finite element method, loading and construction grading of the damare simulated by ANSYS software. Three typical profiles of the dam are select to analysisstress and deformation in completion,stagnant and normal storage period.Through the analysisthe results can be drawn: The maximum tension zone of major and minor principal stress is inthe tip of upstream of the dam contact with the deep-thick overburden layer, in completionperiod. The maximum compression zone of major principal stress is in the bottom of thedeep-thick overburden layer at half the dam. The force to the panel is mainly stress, and theslope near the crest has the small tensile stress. Along the slope direction, the panel issubstantially in compression state and the bottom greater. The panel in sides slope sectionmainly has downstream direction and the value is small, the panel in riverbed section haslarge countercurrent direction displacement. Therefore, the panel appears certain muster andvoid phenomena after completion. After water, the position of the tension zone and maximumcompression zone of major and minor principal stress has little changed. Due to the waterpressure, the panel appears certain degree bending, the tensile and compressive stresses ofpanel increase with the water level increasing. The rate of compressive stresses increase issignificantly greater than the tensile stress.Overall, after water, due to the water pressure, thedam countercurrent displacement has significantly reduced, while the downstreamdisplacement increases, the position of maximum countercurrent displacement move to about30m layer deep under the panel connection with plinth.With water pressure increasing,downstream displacement of the panel drastic increases and countercurrent displacementdecreases,so the void phenomenon disappears. Three kinds of conditions, major principalstress is symmetric distribution, compressive stress in the upper reaches of the dam are significantly greater than the downstream.The minor principal stress is symmetric distributiondeviating upstream a bit.Through the analysis, the maximum tensile stress usually occurs at the junction of paneland plinth of deep-thick overburden layer concrete rock-fill dam.When the panel construction,the connection of the panel with plinth and seams should be noted. Since the panel will beuplift and void during completion, then the concrete panel should have the ability to resistbending deformation.