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1、第41卷,第4期公路工程Vol.41,No.42016年8月HighwayEngineeringAug.,2016晚更新世黃土脫濕-吸濕全過程土水特征曲線研究1112梁燕,程昌夢,杜鑫,李同錄(1.長安大學公路學院特殊地區(qū)公路工程教育部重點實驗室,陜西西安710064;2.長安大學地質工程與測繪學院,陜西西安710054)[摘要]非飽和土土水特征曲線(SWCC)在非飽和土性質的研究中是很重要的。通過現(xiàn)場原位滲水試驗、室內(nèi)試驗,結合數(shù)值反演得到了晚更新世黃土(Q黃土)脫濕和吸濕土水特征曲線。用壓力板儀測量Q黃土脫濕過33程中不同含水率下的吸力,之后用VanGenuchten經(jīng)驗公式對試
2、驗數(shù)據(jù)進行擬合,得出了Q黃土脫濕SWCC曲線3的數(shù)學表達式。在現(xiàn)場滲水試驗的基礎上,用隨機搜索和經(jīng)驗逼近相結合的方法,通過數(shù)值計算反演Q黃土吸濕3過程中的土水特征曲線參數(shù)。此外,還實測了Q黃土豎直向的飽和滲透系數(shù)。結果表明:Q黃土脫濕路徑的進33氣值為4.16kPa,飽和體積含水量為0.52;吸濕路徑的進氣值為3.92kPa,飽和體積含水量為0.48。殘余體積含水量為0.01,殘余飽和度為2.0%,殘余的氣體含量為4.06%。豎直與水平向滲透系數(shù)的比率為1.62,水平向飽和滲-6-5透系數(shù)為7.08*10m/s,豎直向飽和滲透系數(shù)為1.147*10m/s。室內(nèi)實測豎直方向飽和滲透系數(shù)
3、為2.71*-510m/s,反演值與實測值是屬于同一數(shù)量級的。[關鍵詞]晚更新世黃土;土水特征曲線;壓力板儀;現(xiàn)場滲水試驗;滲透系數(shù);進氣值[中圖分類號]U419.4[文獻標識碼]A[文章編號]1674—0610(2016)04—0067—05TheStudyofSoil-WaterCharacteristicCurveofQ3LoessintheDesorptionandAbsorptionProcess1112LIANGYan,CHENGChangmeng,DUXin,LITonglu(1.SchoolofHighway,Chang’anUniversity,KeyLaborat
4、oryofEducationMinistryonHighwayEngi-neeringofSpecialRegion,Xi’an,Shanxi710064,China;2.DepartmentofGeologicalEngineering,Chang’anUniversity,Xi’an,Shanxi710054,China)[Abstract]Soil-WaterCharacteristicCurve(SWCC)isveryimportantintheresearchoftheproper-tiesoftheunsaturatedsoil.TheSWCCsofQloessinthe
5、desorptionprocessandabsorptionprocesswere3obtainedthroughthefieldinfiltrationtest,indoortestsandnumericalbackanalysis.ThematrixsuctionsofQloessindifferentwatercontentsduringtheprocessofdesorptionwaterwereobtainedbythepressure3plateextractor,andtheSWCCwassimulatedwiththeVanGenuchten’sthree-param
6、etermodel.Basedonthefieldinfiltrationtest,obtainedtheSWCCparametersofQloessintheprocessofabsorptionwaterby3themethodofthenumericalbackanalysis.Inaddition,thehydraulicconductivityintheverticaldirectionwasmeasured.Theresultsshowthattheair-entryvalueofQloessinthedesorptioncurveis4.16kPa,3andthesat
7、uratedvolumetricwatercontentis0.52.Theair-entryvalueis3.92kPainabsorptioncurve,andthesaturatedvolumewatercontentis0.48.Theresidualwatercontentis0.01,theresidualdegreeofsaturationis2.0%,andtheresidualaircontentis4.06%.Theratioofthe