資源描述：
《輕骨料預(yù)濕程度對(duì)溷合骨料溷凝土抗凍性能影響》由會(huì)員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、第39卷第1期田鍵等：硅酸三鈣電子背散射衍射數(shù)據(jù)庫(kù)的建立與標(biāo)定·35·硅酸鹽學(xué)報(bào)第39卷第1期Vol.39，No.12011年1月JOURNALOFTHECHINESECERAMICSOCIETYJanuary，2011輕骨料預(yù)濕程度對(duì)混合骨料混凝土抗凍性能影響112孔麗娟，高禮雄，葛勇(1.石家莊鐵道大學(xué)材料科學(xué)與工程學(xué)院，石家莊050043；2.哈爾濱工業(yè)大學(xué)交通學(xué)院，哈爾濱150090)摘要：研究了輕骨料預(yù)濕程度對(duì)不同水膠比混合骨料混凝土28d和90d抗凍性能以及界面區(qū)微觀結(jié)構(gòu)的影響。結(jié)果表明：風(fēng)干輕骨料自身的多孔結(jié)構(gòu)在混凝土內(nèi)部起到了“引氣”的作用，同時(shí)其強(qiáng)烈的吸水作用使
2、得界面層厚度約為預(yù)濕輕骨料的2倍，結(jié)構(gòu)也較致密，故其配制的混凝土抗凍性最優(yōu)。隨著輕骨料預(yù)濕程度的增加，骨料引氣及吸水作用均減弱，故混凝土抗凍性逐漸降低，但預(yù)濕輕骨料后期較強(qiáng)的返水作用可使其附近水泥石中的有害孔含量減少，顯微硬度提高，界面結(jié)構(gòu)得到持續(xù)改善，特別是當(dāng)水膠比較低時(shí)對(duì)提高混凝土長(zhǎng)期抗凍性能有利。當(dāng)水膠比較高時(shí)，由于水泥石結(jié)構(gòu)比較疏松，此時(shí)輕骨料在凍壓下導(dǎo)致內(nèi)部較高的含水率對(duì)混凝土抗凍性的不利影響更為突出。即使飽和預(yù)濕的輕骨料配制的低水膠比混合骨料混凝土，其抗凍性仍優(yōu)于同條件下的普通混凝土。關(guān)鍵詞：輕骨料；預(yù)濕；抗凍性；界面區(qū)；顯微硬度中圖分類號(hào)：TU528.2文獻(xiàn)標(biāo)志碼：
3、A文章編號(hào)：0454–5648(2011)01–0035–06EffectofLightweightAggregatePre-WettingonFrost-ResistanceofCombinedAggregateConcrete112KONGLijuan，GAOLixiong，GEYong(1.SchoolofMaterialsScienceandEngineering,ShijiazhuangTiedaoUniversity,Shijiazhuang050043;2.SchoolofTransportationScienceandEngineering,HarbinInsti
4、tuteofTechnology,Harbin150090,China)Abstract:Thefrost-resistanceofcombinedaggregateconcretepreparedwithdifferentpre-wettingdegreesoflightweightaggregate(LWA)andwater-binderratiosat28dand90dwasinvestigated.ThemicrostructureofLWAandtheinterfacialzonewereexamined,andtheeffectofLWApre-wettingonfr
5、ost-resistanceofconcretewasanalyzed.Theresultsshowthattheporousair-dryLWAcanplaytheroleof“air-entraining”,andthestrongwaterabsorbingeffectcanmakethethicknessofinterfacialzoneofabouttwotimesofthatofprewettedLWA,aswellasthedensificationoftheinterfacialpaste.Thefrost-resistanceofconcreteprepared
6、withair-dryLWAwassuperior.Theair-entrainingandwater-absorbingeffectofLWAbothdecreasedwiththeincreaseofLWApre-wettingdegree,thusleadingtothegradualdecreaseofconcretefrost-resistance.However,thestrongwater-releasingeffectofpre-wettedLWAinlateragecouldimprovetheinterfacialstructurethatdecreasedt
7、hevolumecontentofharmfulporesandincreasedthemicro-hardnessoftheinterfacialpaste,whichcouldfavorthelongtermfrost-resistanceofconcrete,especiallyforconcretewithalowerwaterbinderratio.Forconcretewithahigherwater-binderratio,thehighwatercontentof
