解析不同产品申请ASTM E119耐火测试有什么异同之处

解析不同产品申请ASTME119耐火测试有什么异同之处美标ASTME119标准是对各种建筑结构件进行耐火性能判定，不同的产品，不同的用途，判定依据有相同点，也有不同点。相同点：基本指标相同：基本指标包括完整性，隔热性。耐火完整性：在标准耐火试验条件下,建筑分隔构件当某一面受火时,能在一定时间内防止火焰和热气穿透或在背火面出现火焰的能力。耐火隔热性：在标准耐火试验条件下,建筑分隔构件当某一面受火时,能在一定时间内其背火面温度不超过规定值的能力。不管是什么结构件都需要从完整性和隔热性能等基本方面进行评估。例如：无论是防火门、防火墙，天花板还是其他建筑构件，在试验中都要考察是否出现穿透性裂缝等影响完整性的现象，都要测量背火面温度来判断隔热性。不同点：具体指标数值：不同产品的具体判定指标数值会有差异。例如：不同类型的防火门，根据其使用场景和防火要求的不同，在完整性、隔热性方面的具体温度限值和时间要求会有所差异。一般建筑用的甲级防火门要求耐火极限达到1.5小时，在这1.5小时内背火面的温度升高值等指标要符合相应的严格规定；而一些特殊场所使用的防火门，可能耐火极限要求更高，相关指标也会更严格。测试条件差异：不同产品在试验时的加载方式、加热条件等可能会根据产品特点有所调整。例如：对于墙体试件和楼板试件，加载方式就会不同，墙体可能主要考虑水平方向的推力和压力，而楼板主要考虑垂直方向的均布荷载。此外，一些特殊产品可能需要在标准加热条件的基础上进行适当修改，以更准确地模拟其在实际火灾中的工况。合格判定的侧重点：不同产品由于其在建筑中的功能不同，合格判定的侧重点也有所不同。例如：防火卷帘的判定可能更侧重于完整性和快速响应性能，在火灾发生时能够迅速下落并阻止火势蔓延；而对于一些隔热材料，隔热性则是最为关键的判定因素，其结构稳定性的要求相对较低。判定依据：失去完整性：当棉垫被点燃或者背火面燃烧达10秒钟以上时，被认为试件失去完整性；测试过程中，6mm直径的探棒可穿过裂缝进入炉内且探棒可沿裂缝长度方向不小于150mm；直径25mm的探棒可穿过裂缝进入炉内时，则被认为试件失去完整性。失去隔热性：试件背火面的平均温升超过试件表面初始平均温度140℃或者背火面在任何一点的温升超过该点初始温度180℃时，则被认为试件失去隔热性。失去承重性：在试验过程中试件发生垮塌；或梁板构件的最大挠度、柱构件的轴向变形、柱构件的轴向变形速率超过规定值时，则被认为试件失去承重性。AnalysisofthesimilaritiesanddifferencesbetweendifferentproductsinapplyingforASTME119fireresistancetestTheAmericanstandardASTME119isusedtodeterminethefireresistanceperformanceofvariousbuildingstructures.Differentproductsanddifferentuseshavesimilaritiesanddifferencesinthebasisfordetermination.Similarities:Basicindicatorsarethesame:Basicindicatorsincludeintegrityandthermalinsulation.Fireresistanceintegrity:Understandardfireresistancetestconditions,theabilityofbuildingpartitioncomponentstopreventflamesandhotairfrompenetratingorflamesfromappearingontheback-firesideforacertainperiodoftimewhenonesideisexposedtofire.Fireresistancethermalinsulation:Understandardfireresistancetestconditions,theabilityofbuildingpartitioncomponentstopreventtheback-firesidetemperaturefromexceedingthespecifiedvalueforacertainperiodoftimewhenonesideisexposedtofire.Nomatterwhatkindofstructuralcomponentitis,itneedstobeevaluatedfrombasicaspectssuchasintegrityandthermalinsulationperformance.Forexample:Whetheritisafiredoor,firewall,ceilingorotherbuildingcomponent,itisnecessarytoexaminewhethertherearepenetratingcracksorotherphenomenathataffectintegrityduringthetest,andtheback-firesidetemperaturemustbemeasuredtodeterminethethermalinsulation.Differences:Specificindexvalues:Thespecificindexvaluesofdifferentproductsmayvary.Forexample:Differenttypesoffiredoorshavedifferentspecifictemperaturelimitsandtimerequirementsintermsofintegrityandthermalinsulation,dependingontheirusagescenariosandfireprotectionrequirements.TheClassAfiredoorsusedingeneralbuildingsrequireafireresistancelimitof1.5hours,andthetemperaturerisevalueoftheback-firesurfacewithin1.5hoursmustmeetthecorrespondingstrictregulations;whilethefiredoorsusedinsomespecialplacesmayhavehigherfireresistancerequirementsandmorestringentrelatedindicators.Differencesintestconditions:Theloadingmethodandheatingconditionsofdifferentproductsduringthetestmaybeadjustedaccordingtothecharacteristicsoftheproducts.Forexample:Forwallspecimensandfloorspecimens,theloadingmethodwillbedifferent.Thewallmaymainlyconsiderthethrustandpressureinthehorizontaldirection,whilethefloormainlyconsiderstheuniformlydistributedloadintheverticaldirection.Inaddition,somespecialproductsmayneedtobeappropriatelymodifiedbasedonthestandardheatingconditionstomoreaccuratelysimulatetheirworkingconditionsinactualfires.Emphasisofqualificationjudgment:Duetothedifferentfunctionsofdifferentproductsinbuildings,theemphasisofqualificationjudgmentisalsodifferent.Forexample:Thejudgmentoffireproofrollershuttersmayfocusmoreonintegrityandrapidresponseperformance,andbeabletofallquicklyandpreventthespreadoffirewhenafireoccurs;whileforsomethermalinsulationmaterials,thermalinsulationisthemostcriticaljudgmentfactor,andtherequirementsforstructuralstabilityarerelativelylow.Judgmentbasis:Lossofintegrity:Whenthecottonpadisignitedortheback-firesurfaceburnsformorethan10seconds,thespecimenisconsideredtohavelostitsintegrity;Duringthetest,a6mmdiameterprobecanpassthroughthecrackintothefurnaceandtheprobecanbenolessthan150mmalongthelengthofthecrack;Whena25mmdiameterprobecanpassthroughthecrackintothefurnace,thespecimenisconsideredtohavelostitsintegrity.Lossofthermalinsulation:Whentheaveragetemperatureriseoftheback-firesurfaceofthespecimenexceedstheinitialaveragetemperatureofthespecimensurfaceby140℃orthetemperatureriseoftheback-firesurfaceatanypointexceedstheinitialtemperatureofthepointby180℃,thespecimenisconsideredtohavelostitsthermalinsulation.Lossofload-bearingcapacity:Whenthespecimencollapsesduringthe