1、天津大學(xué)碩士學(xué)位論文不排水條件下粘土的循環(huán)特性及其應(yīng)用姓名：萬濤申請學(xué)位級別：碩士專業(yè)：巖土工程指導(dǎo)教師：王建華20070601ABSTRACTThestudyofclay’SUUcyclicpropertiesisoneofthemostsignificantbranchesingeotechnicalengineeringItsapplicationplaysanimportantroleinevaluatingthecyclicb

2、eatingcapacityofsoftclayfoundationsItisnecessaryforwell—drillingengineeringtOstudythecyclicpropertiesofclayeyfiltercakestoimprovemuddisplacementefficiencyFollowingresearcheshavebeendonebasedonabovereasonsRemoldedprehydra

3、tedbentonitesampleswithdifferentwatercontentwereusedtosimulatefiltercakeswithdifferentstrengthInordertostudythefeasibilityofremovingfiltercakesusingwallsurfaceshearstressmethod，fallingheadpermeabilitytests，directsheartes

4、tsandcyclictriaxialtestswereconductedtodeterminepermeabilityproperties，shearstrengthsandcyclicstrengthofremoldedprehydratedbentoniteResultsshowedthatthestrengthofprehydratedbentonitedegradedundercyclicloadsTherefore，clay

5、eyfiltercakesCanberemovedbycyclicloadswhenvibrationofdrillingfluidpumpisactingonthefiltercakesItisprovedtobeapotentialmethodremovingthefiltercakesduringthemuddisplacementThecyclicpropertiesofsoRclayswerestudiedundertheUU

6、conditionCyclictriaxialtestswereconductedusingundisturbedsaturatedsoftclaysamplesunderthreedifferentconfiningpressuresCyclicstrengthCUlVesandthecyclicaccumulativestrainversusthenumberofcyclesweredeterminedunderdifferentc

7、ombinedstaticandcyclicstressesEffectsofcontiningpressureonthecyclicstrengthandthecyclicaccumulativestrainwerefurtheranalyzedwhentheconfiningpressureWasincreasedto400kPaTestresultsshowedthatthecyclicstrengthandcyclicaccum

8、ulativestrainofthesoRclaydependonthestaticstress，thecyclicstressandthenumberofCyclesTheeffectofconfiningpressureoncyclicpropertiesofclaysCanbeignoredModeltestsofthecircleplateonsoftclayfoundationwereconductedwithcycliclo

9、adsandthecyclicbeatingcapacitieswerealsocalculatedusingthepseudostaticelastoplasticFEMBycomparingtestresultswithcalculationresults，theprinciples，methodsandstepsevaluatingthecyclicbeatingcapacityofsoftclayfoundationswered