考慮卸荷影響的基坑三維計算理論研究.pdf

1、浙江大學(xué)建筑工程學(xué)院碩士學(xué)位論文考慮卸荷影響的基坑三維計算理論研究姓名：郭雷申請學(xué)位級別：碩士專業(yè)：巖土工程指導(dǎo)教師：應(yīng)宏偉20080601Studyon3一DAnalysisTheoryofExcavationConsideringUnloadingImpactsABSTRACTExcavationisactuallyanunloadingprocesstoinnersoilsofpitsConventionalanalysisofr

2、etainingstructuresCannotreflectthespatialeffectsofexcavationonaccountofneglectingunloadingimpactsAnumberofprojectsimplicatethefactthatthemeasureddeformationofretainingwallsisusuallylargerthantheoreticalone，whichrelatesto

3、ignoringtheunloadingdeformationasthispaperfiguredInaddition，almostallofcurrentanalysismethodsforretainingstructureshaveused‘‘m’’methodtodeterminethecoefficientoflateralsubgradereaction，duringwhereneedsmuchexperienceforus

4、ersThispapertakesastudyon3一Danalysisofexcavationconsideringunloadingimpacts，whichwillbepresentedasfollowed1Thecalculatedexpressionsofunloadingstressandunloadingdeformationareeducedwiththeapplicationofminussuperimposedstr

5、esstosimulateexcavationunloading，andthedistributionofstress，deformationandmodulusofdeformationarediscussedItshowsthatrectanglepitscanbesubstitutedbystrippitsbymeetingsomecondition，andthelateraldeformationofinnersoilsarec

6、ommonlycontractiveThedeformationmodulusiSlargerthancompressionmodulusandwillincreaseasthedepthofsubgradeaddingThesecantmodulusofsoilissmallerthanaxialmodulusforstrippits2Thecoefficientoflateralsubgradereactionconsidering

7、unloadingimpactsisgotonthebasisofformerresearchresultsThus，thecoefficientCanbeattainedfromtheexperimentdataratherthantheexperienceofusers3ThedeformationofretainingstructuresCanbedividedintotwostages：oneisunloadingeffecti

8、ngstage；anotherislateralearthandwaterpressureeffectingstageA3Danalysisprogramconsideringunloadingstresspathandlateralunloadingdeformationhasbeendesignedfinally4Threerepresentativeexamplesarecomputedrespectivelyusingthepr

9、ogramandconventionalmethodsTheunloadingimpactstoretainingstructuresarediscussedTheregardofexcavationunloadingcausesthedeformationincreasingfor15％upwardandasmalleffectontheinternalforceofretainingstructuresItshowsthatthel

10、argerpitshavelargerdeformationofretainingwallsandlargerimpactstoenvironmentaroundKeywords：excavationunloading；unloadingstresspath；unloadingdeformation；ratioofunloading；unloadingdeformationmodulus；coefficientoflateralsubg