| The concrete arch dam especially high arch dam usually need to set joints in order tomeet the requirement of temperature control and crack prevention and construction. Thoughthe joints have closure through pressure grouting, but joints between the tensile strength isvery weak usually, and the opening and closing or sliding of the joints will happen indynamic and has great significance on the seismic response of dam structure. In paper theinternational large-general finite element software ABAQUS is used to make threedimensional analysis of the dam in normal operation period，and mainly calculating andanalyzing the dynamic response of arch dam without joints model and with joints model(straight joints and staggered joints) and different interval. First has carried on the staticanalysis of each model, then uses the record in the Koyna seismic wave as the input seismicwave, and calculates the dynamic response, the final analyses and receives the dynamicperformance of arch dam with joints and different type of joints.This paper Focused on the following:(1) Firstly, making three dimensional analysis for the arch dam by usingABAQUS/Explicit module to study the hydrostatic pressure effect and the response onseismic。The Koyna seismic waves as the input earthquake wave, respectively, establishes ano joint model, straight joints model and staggered joints model for analysis, and gets themaximum principal stress nephogram under hydrostatic pressure and the time-history curvesof the displacement of crown under earthquake, the maximum principal stress time-historycurve of dam heel and dam toe maximum principal stress time-history curve, and also getstwo joints model of the opening of the joints time history curve.(2) Analysis shows that the model with transverse joint under hydrostatic pressureapparent stress redistribution; displacement response of arch crown vertex has a significanteffect on seismic because of joints, and compared with the straight joint model，staggeredjoints model has smaller maximum principal stress either dam heel or dam toe in the dynamicanalysis. The joints will open and close in dynamic, and the opening and closing ofreciprocating behavior has a important influence on dam stress response.(3) The settings of Joints will cause stress redistribution of arch dam, and make the threerestraint of arch dam fell, and the maximum principal stress both dam heel and dam toe underdynamic are smaller than no joints. The maximum principal stresses of upstream-crown insetting20m,30m and40m interval of joints are larger than that of no joint model, model about10m interval has to do with no joint. And the valley of the arch dam built by non strictsymmetry, make the dam are characterized by non strict symmetry; so that show the eccentricforce under dynamic, and with the increase of joints interval the stress to the offset from thearch crown and narrow side. In the practical engineering should be pay enough attention to.（4）With the increase of the joints interval，the maximum principal stress of upstreamtop arch crown will increase，and the maximum principal stress of upstream middle archcrown will decreases. The control principal stress of each place is uniform more in select30m joints under dynamic, joints crack and stagger degrees are relatively small. So the arch damwith30m interval joints on seismic performance is better than others.Analysis by comparing, we know that the settings of transverse joints can influence theseismic behavior of the dam, the results showed that the settings of transverse joints lower theoverall of the dam, it causes stress redistribution, the vertex displacement increase of crown;The reciprocating opening and closing of transverse joints heighten the technicalrequirements of the joint surface seepage. According to analysis what the influence ofdifferent stitch length can take to the seismic of arch dam, we know the effects of differentinterval corresponding, it can provide a theoretical basis for the selection of joints interval inactual projects. |
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