資源描述:
《非飽和黏性土抗剪強(qiáng)度的溫度效應(yīng)試驗(yàn)研究.pdf》由會(huì)員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在行業(yè)資料-天天文庫(kù)。
1、JournalofEngineeringGeology工程地質(zhì)學(xué)報(bào)1004—9665/2011/19(1).0137—06非飽和黏性土抗剪強(qiáng)度的溫度效應(yīng)試驗(yàn)研究術(shù)邵玉嫻施斌顧凱唐朝生高磊(南京大學(xué)地球科學(xué)與工程學(xué)院南京210093)摘要為了系統(tǒng)地了解溫度對(duì)黏性土工程性質(zhì)的影響,本文采用南京地區(qū)三種不同礦物成分的黏性土,制成不同含水量和干密度的試樣,在5~45℃條件下,開(kāi)展了抗剪強(qiáng)度試驗(yàn),獲得了三種土的非飽和重塑試樣的抗剪強(qiáng)度與溫度的關(guān)系。試驗(yàn)結(jié)果表明:黏性土的黏聚力隨溫度升高呈線性變化;親水礦物含量較高的黏性土抗剪強(qiáng)度對(duì)溫度變化較敏感,黏聚力隨著
2、溫度的升高而降低,表現(xiàn)為強(qiáng)度的熱軟化現(xiàn)象;親水礦物含量較低的黏性土,當(dāng)含水量較低(W≤17%)時(shí),表現(xiàn)為強(qiáng)度的熱硬化現(xiàn)象,當(dāng)含水量較高(w≥22%)時(shí),表現(xiàn)為強(qiáng)度的熱軟化現(xiàn)象,且干密度越高的試樣,強(qiáng)度的溫度效應(yīng)越明顯。論文還分析了非飽和黏性土抗剪強(qiáng)度的熱硬化和熱軟化的內(nèi)在機(jī)理。關(guān)鍵詞非飽和黏性土溫度強(qiáng)度熱軟化熱硬化中圖分類號(hào):TU441文獻(xiàn)標(biāo)識(shí)碼:ADIRECTSHEARTESTFoRTEMPERATUREEFFECToNSHEARSTRENGTHoFUNSATURATEDCLAYEYSoILSSHAOYuxianSHIBinGUKai’I’AG
3、ChaoshengGA0Lei(SchoolofEaahSciencesandEngineering,NanjingUniversity,Nanjing210093)AbstractInordertosystematicallystudythetemperatureeffectontheengineeringpropertiesofclayeysoils,labo-ratorytestwasconductedtoevaluatetherelationsbetweentemperatureandshearstrengthofunsaturatedr
4、emodelingsoilsamples.AmongthreecommontypesofclayeysoilsinNanjingwithdiferentmineralcomposition,directsheartestsofsoilsamplesindifferentmoisturecontentanddrydensityhavebeendoneintherangeof5~5O℃.There-suhsindicatethatthefollowing.(1)thecohesiveforcechangemainlyandlinearlywithth
5、etemperature.(2)theshearstrengthofclayeysoilswithhighercontentofhydrophilicmineralismoresensitivetotemperaturechange.(3)thecohesiveforcedecreasewiththetemperaturerise,showingthermal—softeningonstrength.(4)f0rclayeysoilswithlowercontentofhydrophilicmineral,whenthemoistureconte
6、ntislower(W≤17%),theshearstrengthshowsthethermo—hardeningphenomenon,howeveritshowsthethermal—softeningphenomenonwhenthemoisturecontentishigher(WI>22%),andthetemperatureeffectonshearstrengthismoreobviouswhenthedrydensityofsampleishigher.Moreover,themechanismofthermalsofteninga
7、ndhardeningofunsaturatedclayeysoilsisana—lyzed.KeywordsUnsaturatedclayeysoils,Temperature,Strength,Thermal-softening,Thermal—hardening收稿日期:2010—08—20;收到修改稿日期:2011—0l一14.基金項(xiàng)目:國(guó)家自然科學(xué)基金重點(diǎn)項(xiàng)目(40730739).第一作者簡(jiǎn)介:邵玉嫻,從事工程地質(zhì)和環(huán)境巖土工程研究.Email:shaoyuxianO127@163.corl138JournalofEngineering
8、Geology工程地質(zhì)學(xué)報(bào)2011顯,根據(jù)作者所在的南京大學(xué)地球環(huán)境計(jì)算工程研1引言究所城市熱島效應(yīng)課題組對(duì)南京地區(qū)淺層土體溫度的長(zhǎng)期觀