突发灾害和力学白以龙非线性力学国家重点实验室,力学研究所,中国科学院北京,中国10019020100226科普论坛内容1。自然和工程的突发灾害2。演化诱致突变3。灾害预测和健康管理29thICSUGA(2005):NaturalandHuman-InducedHazards•Frequency:thenumberofeventsisincreasingdramaticallyHazardsanddisasters•TheeconomicimpactsofnaturaldisastersareincreasingdramaticallyFractionintopconstructionsaroundtheWorld:Topbuildings:6/10Topcable-stayedbridge:7/10(武汉天兴洲长江公铁大桥L=504米,H=189米)TopLong-spanSuspensionBridges:3/10(苏通大桥主桥,L=1088m,H=306m)DAMheight:锦屏一级拱坝高305m,小湾拱坝高297m…………………………………………………………………..DisastersinChina:Earthquake:44(﹥M7),5(﹥M8)(20thCentury)Typhoon:7/year,…….例1:(自然界)2001年11月昆仑山8.1级地震.断裂带东经90-94度ViewatmajorseismicrupturezoneandoffsetsofdamandhighwayoftheMs8.1Kunlunearthquake(from“AnalbumofgeologicalhazardsandactivefaultsalongQinghai-Tibetrailway”,)倒塌前的雷峰塔1924年9月25日下午倒塌例2:(工程)1988年,Aloha航线的一架波音737在飞行中顶部脱落。影片“九霄惊魂”(MiracleLanding)美国家交通安全委员会结论:由于疲劳等多因素形成若干小裂纹,虽均在承载容限内,但空间位形却非常不利。尺度范围:mm106例3:(近代工程)2004年5月23日清晨巴黎戴高乐机场屋顶坍塌(连接两个停机坪的大型走廊的钢筋水泥顶棚发生坍塌,约五十米宽,三四十米长)例4:(近代工程)塔科马大桥的坍塌•1940年11月7日,享有当时的世界的单跨桥之王的塔科马大桥,被一阵不太强的风颳跨,坍塌。例5(有过程记录)卡门涡街1911年在哥廷根,博士生希门茨研究水流中的圆柱表面的压力.测出的压力总是波动不已.“希门茨以日耳曼人那股傻劲,将圆柱磨得滚圆,将水槽精磨固定,但是,圆柱总是晃动”“到周末,我下决心来探索晃动的原因。我考虑了两种可能性。我假设涡流从圆柱体顶部和底部交替出现,我清晰地想象到,若两股涡流按一定稽核图案排列,其外形就会稳定”经过仔细的“做”---力学和数学分析,求解,再实验,冯。卡门终于发现了“卡门”涡街.Karman涡街Re=76AfterLIZhanghua(北京时间2003年2月1日22:00时)哥伦比亚号最后照片残片的浓烟空间舱残骸左翼上的裂纹例6:(高科技)•STS-51-Lwasthe25thlaunchofaSpaceShuttleandthetenthlaunchoftheChallenger.Itexploded73secondsafterlaunchonJan28,1986,becauseofsolidrocketboosterfailure.CAIBfinalreportAug26,2003•Majorfindings•82secondsafterlaunchalargepieceoffoaminsulatingmaterialfromtheexternaltankbrokefreeandstrucktheleadingedgeoftheshuttle'sleftwing,damagingtheprotectivecarbonheatshieldingtiles.Thisdamageallowedsuper-heatedgasestoenterthewingstructureduringre-entryintotheearth'satmosphereandcausedthedestructionoftheColumbia.•ThefirstrecommendationwasthatNASAdevelopaninspectionplantoexaminetheReinforcedCarbonCarbon(RCC)systemcomponents(R3.3-1).TheRCCsystemisusedonthepartsoftheorbiterthataresubjectedtothegreatestamountofheatduringreentry.Theseareasincludetheleadingedgesofthewings,theareaaftofthenosecap,andtheareaaroundtheforwardorbiter/externaltankattachmentstructure.TheBoardfoundthatthecurrenttechniquesthatareusedtoexaminetheRCCsystemareincapableofthoroughlyassessingtheRCC’sstructuralintegrity,itssupportingstructure,andtheattachedhardware.TheCAIBbelievedthatNASA“shouldtakeadvantageofadvancednon-destructiveinspectiontechnology”tomitigatefuturerisktothespaceshuttlesandcrew.[i]回顾历史,每一批典型的灾难性事故,都导致力学和工程健康管理的进步•自由轮断裂------断裂力学–断裂韧度•彗星号事故------喷气机设计(民用化)•航天飞机和飞机事故------健康管理内容1。自然和工程的突发灾害2。演化诱致突变3。灾害预测和健康管理A.演化诱致突变(EIC)EvolutionInducedCatastrophe一根稻草压死一头牛。Thelaststrawbreaksthecamel’sback0.02.0x10-64.0x10-66.0x10-68.0x10-60.08.0x1041.6x1052.4x105(Pa)0.02.0x10-64.0x10-66.0x10-68.0x10-60.08.0x1041.6x1052.4x105(Pa)“最后一根稻草”的数值模拟(afterRongF)10020030040001020Time(s)092709460947(0948)0862P(kN)0005MarbleBNo.10704x1028x102*/t00050862092709460947(0948)-0.021-0.018-0.015-0.012-0.009-0.006-0.00300.0030.006突发灾变的岩石实验(948)B.样本个性行为SampleSpecificity(numerical)3mm1355CriticalSensitivityinRockExperimentsPAEsensorGabbrosampleDisplacementcontrol0.02mm/minExtensometer0.109mmmm125.0~07.0ccuu357710044~304eventseventsNNSamplenumber:151样本个性行为(afterXuXH)SampleSpecificandTrans-scalesensitivityevolution蝼蚁之穴,溃堤千里。OneantholemaycausethecollapseofathousandmiledykeC.跨尺度敏感性从微观到宏观的力学“敏感隧道”xoxooxoooxoooooxooooooooxoooooooooxoxoxooooxooooooxooooooooxooooooooooooooxx….xxxx….xxxxxxx….xxxxxxxxxxx….xxxxxxxxxxxxxxxxx….xxxxxxxxxxxxxxxxxxxxxxxxx….xxoxooooxooooooxooooooooxooooooooooooooxxxxooooxooooooxooooooooxooooooooooooooxxxxxooooxooooooxooooooooxoooooooooooooo(a)(b)Quasi-Fabonacciseries(1,2,3,5,8,13,20,30,………)ofbreakingisasensitivemicrostructure跨尺度敏感性的一个表现–涨落剧增10020030040010-410-3(22*)Time(s)10-510-410-310-210-100050947蝼蚁之穴,溃堤千里.千里之堤以蝼蚁之穴溃,百尺之室以突隙之烟焚.固曰,白圭之行堤也塞其穴,丈人之慎火也涂其隙.是以白圭无水难,丈人无水患.此皆慎易以避难,敬细以远大者也.战国.韩非“韩非子.喻老”蚍蜉撼大树,可笑不自量.唐.韩愈“调张籍”571003.8NSizeofPhasespace(Möbiusinversion)whenN=200,),(1,!!)!()(nNnddnNdndNNnNd)!(!!,nNnNnN如果用每秒亿亿(10**16/秒)次计算机,每秒算出一个状态的演化,需要用10**41秒,约10**34年。即使,敏感区域只占百万分之一,仍需10**28年。(宇宙年龄约为10**10年)。难点:非线性复杂性浑沌连续分叉ContinuousbifurcationsSelf-sustainablecatastrophicruptureDrucker’sunstableSuccessivebifurcationsmultiplefixedpointsChaos内容1。自然和工程的突发灾害2。演化诱致突变3。健康管理和灾害预测简化模型:差分时滞方程:X:累积数字;t:日数.K:一日内一个病人感染人数.k:公众和政府的抗感染措施,0k1:感染影响滞后效应Xc措施不及时度m措施力度(1)[()]XKkXXtSARS控制趋势预测1exp[()*()]/mqXxkXcXCXcXk1ComparisonbetweenHKandBJR0=KτXcmqBJ2.15819804.1370.0647HK2.79210361.2990.0394差不太多北京比香港力度强下降快香港比北京及时差不太多05010015005001000150020002500XtrealbjXPHM(PrognosticsandHealth-ManagementSystems)Goals:IncreaseSafetyCutCostsCase:JSF(JointStrikeFighter)DOD,DARPA$2.2billionJSFconceptdemonstrationprogram(Nov.1996-)Boeing&LockheedMartinFromBecker,Ind.Phys.1998,4X35:LockheedMartinSix-layerHierarchyforIntegratedPredictiveDiagnosticsThoughmissiondemandsaremadeatthetoplevel,failureisinitiatedatthelowestlevelSornette