Evaluation And Reinforcement Of The Anti-earthquake Safety For Sand-shell Dam With Clay-center-wall

China is a many earthquakes nation, the dam in reservoir belongs to the lifeline projects of earthquake defending. During the middle period of 20 century, our country has built a lot of reservoirs, among them about 1/3 are the clay-center-wall dams. Most of the dams have not the anti- earthquake design or them defending standards are shortage, and have induced a great many of earthquake-harm projects. Therefore, how to proceed to the anti- earthquake safety evaluation to them with reinforcing, repairing, have become the critical and difficult problems of the danger-obviating and reinforcing projects of the dams in reservoir our country current face.For the sake of the above problems in solution, this article makes the clay-center-wall dams of Dongzhou Reservoir as the typical model, doing primary works as follow:First, commence from the systemic analysis of earthquake characters of dam district, by the dam district earthquake analysis, and put forward the earthquake intensities, acceleration topmost values and the charts of earthquake designing reaction in the exceed-rates (63%, 10% and 3%)of the dam district in future 50 years.Second, taking moving-three-axis experiments for means, using equivalent-nonlinear-sticky-flexibility model as moving-configuration models, by the liquefacient characteristics of the materials of dam, moving-intensity, moving flexibility modulus and damping experiment, research the motive characteristics of the dam materials systemic and put forward the dynamics indexes.The third, taking rhombus-limited-cell method for means, with the Duncane~Zhang models as the model of statics account, working out frank stress and shearing strength of each unit's original states .Adopting general stress method of the soil equivalent-nonlinear-sticky- flexibility and Wilson — 9 gradual integral method ,work out each unit's equivalent-horizontal-earthquake shearing strength; using Ceat's method to analyze dam's safety of anti-liquefaction, and make a picture of it, and have solved the problems of confirming the degree and position of equivalent and estimating dam anti-earthquake capable scientific.The fourth, joining together the engineering research results in local and abroad of reinforcing soil dams, reasonably confirm the engineering measures that used to reinforcing the soil dams, and have the reinforcing results proceeded the verification, solving the hard nut of anti-earthquake.