再生混凝土力学性能试验与应用效益分析--华北水利水电

华北水利水电学院硕士学位论文再生混凝土力学性能试验与应用效益分析姓名：刘云霞申请学位级别：硕士专业：市政工程指导教师：邢振贤2011-05I250%100%0.3%0.6%1628IIANALYSISOFMECHANICALPROPERTIESANDAPPLICATIONBENEFITOFRECYCLEDCONCRETEABSTRACTConcreteforthewasterecyclinghasincreasinglybecomeahighpriorityinmanycountries.Withthethedevelopmentofconstruction,alargenumberofbuildingdemolitionandconstructionwastehasgeneratedseriouspollutiontotheenvironment,andthebuildingconstructionoflargescalerequiresalotofnaturalaggregateandnaturalaggregateminingonthedestructionofthenaturalenvironmentisalsoveryserious.Toaddressthesecondaryprocessingofconstructionwaste,tosearchthenativeaggregateconcretealternatives,recycledconcretewasstudiedinthispaper.Basedontheresearchstatushomeandabroad,thispaperdescribedtheprocessingofrecycledaggregate,studiedthestrengtheningmechanismandprocessmeasuresofrecycledaggregate.Thenselectedtwotargetstrengthsofrecycledconcreteformixdesign,foreachofwhich50%and100%recycledcoarseaggregatereplacementwereused.Afterthatadded0.3%and0.6%oftheairentrainingagent,soformedatotalof16groupsofconcretetestspecimens,usingfortestingtheslumpandgascontentoftherecycledconcretemixture,thecompressivestrength,splittingtensilestrength,flexuralstrengthandelasticmodulusoftherecycledconcreteafter28days.Atthesametimestartedthemachine,tomeasurethecycletimesoffreezingandthawingofrecycledconcrete.Theresultsshowthat:water-cementratioofrecycledconcreteisthemainfactorontheslump;addingamountofair-entrainingagentofrecycledconcreteisthemainfactorofthegascontent.Whenwater-cementratioissmall,thestrengthandmodulusofelasticityofrecycledconcreteisstrong;amountofrecycledaggregateinfluencestheflexuralstrengthandelasticmodulusofrecycledconcrete.Therecycledconcretewithasmallerwater-cementratiohasabetterfrostresistance.Thereforewecandeterminethatthewatercementratioisthemainfactorofthefrostresistanceofrecycledconcrete,whilegascontentoftheaverageconcreteisgenerallyconsideredthemainfactorofthefrostresistance.KeyWords:Recycledaggregate;recycledconcrete;mechanicalproperties;frostdurability;applicationbenefits:111.170%34%[1]3050[2]3040[3]1980550016200520030000.3/400034136040001996199120001010[4]228451314[5]75[6]1.5[3]RecycledAggregateConcreteRAC1.220701.2.11976RILM2080203[7]199920MPa2040MPa[8]198980[9]1998[10]26cm19cm7cm[11]NBNB21--001(1988)[12][13]20264CYCLEAN1001/3[14][15]1977[16]1991123[8]199219921997JISJIS[17]50%4100t/h[18][19]1.2.21997[20]30%[8]80%19901997[8][21][22][23][24][25]1.353622.12.1.1DB/TJ08-002-98d=50mmh=100mmd=50mmh=50mmGB/T50081-20022-124.5MPa~34.7MPa2-1Table2-1Coredrillingmethodfortestingconcretestrength123456FkN514856646867MPa25.9924.4628.5432.6134.6534.142cuPfrαπ=αh/d=1α=12.1.22-15mm40mm5mm40mm740mm2-22-12-2Figure2-1RecycledcoarseaggregateproductionflowchartFigure2-2Strengthenmachineryofrecycledcoarseaggregate2.1.3DM-2-282-2Table2-2Technicalperformanceofrecycledcoarseaggregatemmkg/m3kg/m3%%5~40239013303.7714.22.22.2.132.5MPa0.0070.2mmGB/T1345-200580m10%45m30%2-32-3Tab2-3Finenessofcementgg%%32.5503.5710.0913mm2630mm2630mm2-42-4Tab2-4TheamountofwaterfornormalconsistencyofcementgmLmm%32.550015028.13045min390min2-52-5Tab2-5Settingtimeofcementpastehminminhminh32.523845343101032.5ISOISOGB/T17671-2002112-322-45——40mm×40mm2-3Figure2-3CementMixer21450±2gISO1350±5g225±1mL±1g±1mL230s30s30s30s90s15s60s±1s3300g60601190°420±1≥90%20±15350±10N/s2-4Figure2-4Testingmachineofcementmortarflexuralstrength2-10.01MPa35.1bLFRff=2-1Rf——MPaFf——NL——mmb——mm640mm×40mm2400±200N/s2-20.1MPaAFRCC=2-212RC——MPaFC——Nb——mm²2-5Figure2-5Electro-hydraulicpressuretestingmachineandstandardcompressionfixture7ISOGB/T17671-19990.01MPa0.1MPa0.1MPa0.1MPa32-632.5Tab2-6Qualityindicatorsof32.5Portlandcement%10.03.25%5.02.05min45200%3.52.74min600290%5.02.50%302-732.5Tab2-7Strengthindexof32.5PortlandcementMPaMPa3d28d3d28d2.55.511.032.53.57.416.342.22.2.275%13115.00mm2-102m1)3105±5m0)4m25ρ2-310kg/m1000)(1200×−−+=tmmmmαρ2-3ρ——kg/m3m0——g)m1——gm2——gtα——2-82-8Tab2-8Crushedstoneorgravelunderdifferenttemperature,thecorrectionfactoroftheapparentdensity1516171819202122232425tα0.0020.0030.0030.0040.0040.0050.0050.0060.0060.0070.0081422-1111——100kg100g2——10L34——105±52140kg105±5250mmm23Lρ2-410kg/m3100012×−=VmmLρ2-4Lρ——(kg/m3m1——kgm2——kgV——L32-11Lυ2-51%%100)1(×−=ρρυLL2-515Lυ——%Lρ——kg/m3)ρ——kg/m3)2-1111——20kg,20g2——105±53——1.25mm80µm4——10L5212-9105±52-9Tab2-9Atleastthequalityofsampletheclaycontenttestneeded(mm)10.016.020.025.031.540.063.080.0(kg)2266101020202m0150mm2h1.25mm80µm1.25mm80µm80µm3480µm1680µm105±5m15cω2-60.1%%100010×−=mmmcω2-6cω——%0m——g1m——g0.2%32-1111300kN22-635kg5kg410.0mm20.0mm172-6Figure2-6Crushedvalueindexdetector2110.0~20.0mm10.0mm20.0mm3kg3210mm25100mm3160300s200kN5sm02.50mmm14αδ2-90.1%%100010×−=mmmαδ2-9αδ——mo——gm1——g32-11182-10Tab2-10Atleastthequalityofsampletheapparentdensitytestneeded(mm)10.016.020.025.031.540.063.080.0(kg)2.02.02.02.03.04.06.06.02-11Tab2-11Qualityofnaturalgrossstonemmg/cm3kg/cm3%%%5~102.71158041.90.36.410~202.67156043.90.185.42.2.360min~90min200mm2.32.3.12854MPaC20~C250.3540.4MPa192.3.2JGJ55-20002.3.3C25C35100%50%0.3%0.6%82-12202-12