【英文版】课件：钻芯法检测混凝土强度课件讲解

钻芯法检测混凝土强度StructuralinspectionofbuildingengineeringTestingconcretestrengthbycoredrilling目录一检测概述仪器设备二现场检测三数据处理四DirectoryOneDetectionoverviewTwoInstrumentandequipmentThreeFieldinspectionFourDataprocessing一检测概述OneDetectionoverview基本原理Coredrilling利用专用钻机，从结构混凝土中钻取芯样以检测混凝土强度或观察混凝土内部质量的方法。对结构混凝土造成局部损伤，是一种半破损的现场检测手段。钻芯法检测概述DetectionoverviewBasicprincipleCoredrillingMethodbywhichacoresampleisdrilledfromastructuralconcreteusingaspecialdrilltotestthestrengthoftheconcreteorobservetheinternalqualityoftheconcrete.Partialdamagetostructuralconcreteisakindofspotdetectionmethodofsemi-damage.检测钻（冲）孔检测人工挖孔现浇混凝土灌注桩成桩质量的一种有效手段不受场地条件的限制适用于大直径混凝土灌注桩的成桩质量检测钻芯法基本原理检测概述DetectionoverviewBasicprincipleCoredrillingTestdrilling(punching)holesDetectmanualdiggingThequalityofcast-in-placeconcretepileisaneffectivemeansNotlimitedbysiteconditionsItissuitableforqualitytestingoflargediameterconcretecast-in-placepiles钻芯法特点检测混凝土的强度、裂缝、接缝、分层、孔洞或离析等缺陷直观精度高钻芯时对结构造成局部损伤所代表的区域也是有限的比较笨重移动不够方便测试成本也较高钻芯后的孔洞需要修补优点缺点检测概述DetectionoverviewCharacteristicsofcoredrillingmethodadvantageshortcomingsDetectdefectssuchasstrength,cracks,joints,layering,holesorsegregationofconcreteintuitiveHighprecisionLocaldamagetothestructureduringcoredrillingThearearepresentedisalsolimitedRelativelybulkyNoteasytomoveTestingcostsarealsohigherTheholeaftercoredrillingneedsmending标准规范《钻芯法检测混凝土强度技术规程》(JGJ/T384-2016)检测概述DetectionoverviewStandardspecificationTechnicalSpecificationforTestingConcreteStrengthbycoreDrillingMethod(JGJ/T384-2016)二仪器设备TwoInstrumentandequipment钻芯机构造钻芯机手持钻芯机路面钻芯机1——电动机2——变速箱3——钻头4——膨胀螺栓5——支承螺丝6——底座7——行走轮8——立柱9——升降齿条10——进钻手柄11——堵盖钻芯机的主要构造组成仪器设备

InstrumentandequipmentCoredrillingmechanismCoredrillingmachineHand-heldcoredrillingmachineRoadcoredrillingmachineThemainstructureofthecoredrillingmachine1--Motor2--Gearbox3--Drill4--Expansionbolts5--supportingscrews6--Base7--walkingwheel8--column9--liftingrack10--Drillhandle11--Coverblocking选用要求仪器设备钻芯机应具有足够的刚度、操作灵活、固定和移动方便，并应有水冷却系统，控制进钻速度。钻取芯样时宜采用金刚石或人造金刚石薄壁钻头。锯切芯样时使用的锯切机和磨芯机，应具有冷却系统和牢固夹紧芯样的装置。芯样宜采用补平装置（或研磨机）进行芯样端面加工。补平装置除应保证芯样的端面平整外，尚应保证芯样端面与芯样轴线垂直。探测钢筋位置的磁感仪，应适用于现场操作，最大探测深度不应小于60mm，探测位置偏差不宜大于±5mm。钢筋定位仪磨平器量角器钢尺游标卡尺取芯机切割机补平器塞尺压力机

InstrumentandequipmentSelectionrequirementSteelbarlocatorCoringmachinepolisherpresslevelerCuttingmachinefeelergaugeprotractorThecoredrillingmachineshouldhavesufficientstiffness,flexibleoperation,easytofixandmove,andshouldhaveawatercoolingsystemtocontrolthedrillingspeed.Diamondorartificialdiamondthin-wallbitisusedwhendrillingcoresample.Thesawingmachineandcoregrindingmachineusedwhensawingcoresampleshouldhavecoolingsystemandfirmlyclampingcoresampledevice.Coresampleshouldbeprocessedbylevelingdevice(orgrindingmachine).Thelevelingdeviceshallnotonlyensuretheendfaceofthecoresampletobeflat,butalsoensurethattheendfaceofthecoresampleisperpendiculartothecoreaxis.Themagneticsensorusedtodetectthesteelbarpositionshouldbesuitableforfieldoperation.Themaximumdetectiondepthshouldnotbelessthan60mm,andthedetectionpositiondeviationshouldnotbegreaterthan±5mm.三现场检测ThreeFieldinspection现场检测芯样加工芯样测量芯样试压芯样钻取钻取部位受力较小结构或构件受力较小的部位。有代表性混凝土的强度有代表性的部位。避开主筋避开主筋、预埋件和管线的部位。便于操作便于钻芯机安放和操作的部位。FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestLessstressrepresentativeApartofastructureormemberunderlessstress.AvoidthemainbarAvoidthemainreinforcement,embeddedpartsandpipelines.EasytooperateApositionthatfacilitatestheplacementandoperationofthecoredrillingmachine.单个构件数量批量构件数量现场检测芯样加工芯样测量芯样试压芯样钻取芯样试件的数量应根据检验批的容量确定。Thenumberofcorespecimensshallbedeterminedaccordingtothecapacityofthetestlot.标准芯样试件的最小样本量不宜少于15个，小直径芯样试件的最小样本量应适当增加。Theminimumsamplesizeofstandardcorespecimenshouldnotbelessthan15,andtheminimumsamplesizeofsmall-diametercorespecimenshouldbeappropriatelyincreased.有效芯样不少于3个;Nolessthan3effectivecoresamples;较小构件不少于2个。Therearenotlessthan2minorcomponents.FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestBatchcomponentquantityNumberofindividualcomponents现场检测芯样加工芯样测量芯样试压芯样钻取芯样试件切割前应标注好芯样编号；芯样加工时，一般情况下将影响强度试验的缺边、掉角、钢筋等部分切除，为检测砼受冻层或疏松层强度时，切割加工中要注意保留这一部分混凝土；芯样试件内不应含有钢筋，也可含有1根直径不大于10mm的钢筋，且钢筋应与芯样轴线垂直并离开端面10mm以上。切割加工FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestcuttingCorespecimennumbershouldbemarkedbeforecutting;Incoresampleprocessing,themissingedge,Angleoff,reinforcementandotherpartsthataffectthestrengthtestaregenerallycutout.Inordertodetectthestrengthoffrozenorlooselayerofconcrete,attentionshouldbepaidtokeepthispartofconcreteincuttingprocessing;Thecorespecimenshouldcontainnosteelbar,oronesteelbarwithadiameterofnomorethan10mm,andthesteelbarshouldbeperpendiculartothecoreaxisandmorethan10mmawayfromtheendface.现场检测芯样加工芯样测量芯样试压芯样钻取硫磺胶泥补平：简单、方便、效率高，容易保证补平质量，补平后即可进行抗压试验，其缺点是硫磺蒸气中含有二氧化硫等有害气体。端面修正水泥砂(净)浆补平：比芯样强度高一个强度等级、水泥砂浆补平、养护室内进行养护补平法补平层厚度不宜大于2mmFieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestFacecorrectionLevelingmethodThethicknessofthelevelinglayershouldnotbegreaterthan2mmSulfurcementleveling:simple,convenient,highefficiency,easytoensurethequalityoftheleveling,afterthelevelingcanbecarriedoutcompressiontest,itsdisadvantageisthatsulfurvaporcontainssulfurdioxideandotherharmfulgases.Cementsand(net)mortarleveling:onestrengthgradehigherthanthecoresamplestrength,cementmortarleveling,curinginthecuringroom现场检测芯样加工芯样测量芯样试压芯样钻取平均直径芯样高度平整度垂直度用游标卡尺测量芯样上中下部;在相互垂直的两个位置上取其六次测量的算术平均值作为平均直径;精确至0.5mm。用钢板尺或卡尺测量；精确至1mm。用游标量角器分别测量两个端面与轴线间的夹角；取最大值作为垂直度；精确至0.1度。用钢板尺或角尺紧靠在芯样端面上；一面转动钢板尺一面用塞尺测量与芯样之间的缝隙（取最大值）。FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestMeandiameterCoreheightperpendicularityflatnessCementsand(net)mortarUseverniercalipertomeasurethemiddleandlowerpartofcoresample;Thearithmeticmeanvalueofsixmeasurementsattwoperpendicularpositionsistakenasthemeandiameter.Accurateto0.5mm.Tomeasurewithasteelrulerorcaliper;Accurateto1mm.TheAnglebetweenthetwoendfacesandtheaxiswasmeasuredbyavernierprotractor.Takethemaximumvalueasperpendicularity;Accurateto0.1degree.Withsteelrulerorsquareclosetothecoreendface;Thegapbetweenthesteelplaterulerandthecoresampleismeasuredwiththefeelerruler(takethemaximumvalue).现场检测芯样加工芯样测量芯样试压芯样钻取高径比小于0.95高径比大于1.05芯样不垂直度大于1°在100mm长度内大于0.1mm

无效芯样任一直径与平均直径相差大于1.5mm芯样高度垂直度平整度平均直径芯样有较大缺陷FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestCoreheightperpendicularityMeandiameterTheheighttodiameterratioislessthan0.95Height-diameterratiogreaterthan1.05flatnessGreaterthan0.1mmwithin100mmlengthAnydiameterthatdiffersfromthemeandiameterbymorethan1.5mmThecoresamplehasmajordefectsInvalidcoresample现场检测芯样加工芯样测量芯样试压芯样钻取干燥状态下试验的试件通常比经过浸湿的芯样强度高7%左右潮湿干燥FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestdampdryingSpecimenstestedinthedrystateareusuallyabout7%strongerthancoresamplesthathavebeensoaked现场检测芯样加工芯样测量芯样试压芯样钻取抗压试验的操作应符合现行国家标准《普通混凝土力学性能试验方法标准》（GB/T50081）中对立方体抗压强度的规定。芯样试件的混凝土抗压强度fcu,cor＝Fc/Afcu,cor——芯样试件的混凝土抗压强度值（MPa）fcu,cor——Concretecompressivestrengthofcorespecimen(MPa)Fc——芯样试件的抗压试验测得的最大压力（N）Fc——Maximumcompressivepressureofcorespecimen(N)A

——芯样试件抗压截面面积（mm2)A

——Compressivesectionareaofcorespecimen(mm2)FieldinspectionCoresampledrillingCoreprocessingCoremeasurementCoresamplepressuretestTheoperationofthecompressivetestshallcomplywiththecurrentnationalstandard"StandardofTestMethodsforMechanicalPropertiesofOrdinaryConcrete"(GB/T50081)forthecompressivestrengthofthecube.Concretecompressivestrengthofcorespecimen四数据处理FourDataprocessing强度计算数据处理上限值fcu,e1=fcu,cor，m-k1Scor，精确0.1MPa下限值fcu,e2=fcu,cor，m-k2Scor，精确0.1MPa

检验批的混凝土强度推定值应计算推定区间：附表：

芯样平均值fcu,cor，m，精确0.1MPa标准差Scor，精确0.1MPak1、k2推定区间上限值系数和下限值系数，查附录Afcu,e1和fcu,e2所构成推定区间的置信度宜为0.85fcu,e1与fcu,e2之间的差值不宜大于5.0MPa和0.10fcu,cor,m两者的较大值宜以fcu,e1作为检验批混凝土强度的推定值DataprocessingStrengthcalculationTheputativevalueoftheconcretestrengthoftheinspectionlotshallbecalculatedwithintheputativeinterval:Upperlimitfcu,e1=fcu,cor,m-k1Scor,accurate0.1MPaLowerlimitfcu,e2=fcu,cor,m-k2Scor,accurate0.1MPaCoresampleaveragefcu,cor,m,accurate0.1MPaStandarddeviationScor,accurate0.1MPaUpperlimitcoefficientandlowerlimitcoefficientofconstructiveintervalk1andk2,refertoAppendixAAttachedtable:fcu,e1andfcu,e2constituteaconstructiveintervalofconfidenceshouldbe0.85Thedifferencebetweenfcu,e1andfcu,e2shouldnotbegreaterthan5.0MPaand0.10fcu,cor,mItisadvisabletotakefcu,e1astheconstructivevaluesofthestrengthofthetestbatchconcrete思考题钻芯法