摘要:
采用小波包分解和重构的方法,将复杂的实测爆破地震波速度信号转化为多个简谐波的叠加,将
爆破速度荷载作用下结构的动态响应问题转化为一系列简谐荷载作用下的动态响应问题。通过提出速度因
子的新概念并反映在爆破地震效应计算模型中,考虑了结构动态响应中瞬态响应的影响。同时爆破地震效应
计算模型中又融入了归一化的能量比例,在考虑爆破荷载频率的影响时仅需考虑占有相当能量比例的优势
频率的综合作用。然后,在该计算模型基础上提出了一个新的爆破地震效应安全判据。该判据能反映出爆破
激励荷载作用下结构速度响应大小与结构特性、爆破荷载幅值、频率(包括多个优势频率)、持续时间及能量比
例等参数的关系。最后结合实际工程案例,通过使用基于小波包技术的爆破地震效应计算模型与时程分析
法,分别求解出速度响应幅值并将结果进行对比,验证了所建模型的可行性。
Abstract:
Complexmeasuredvelocitysignalsofblastingvibrationaretransformedintothesuperpositionofseveralsimpleharmonicwavesbythewaveletpac
etdecompositionandreconstructiontechniques.
Inthisway,theproblemofstructuraldynamicresponseundertheactionofblastingvelocity
loadbecomestheproblemofthatunderaseriesofsimpleharmonicloads.Byintroducinganewconceptofvelocityfactorintothecomputationalmodelofblastingvibrationeffect,
thecontributionof
structuraltransientresponseisconsideredintostructuraldynamicresponse.Atthemeantime,normalizedenergyproportionisaddedtothecomputationalmodel,
andonlydominantfrequenciesofrelativelylargeenergyproportionscanbeincludedwhenconsideringtheinfluenceofblastingloadfrequencies
Then,onthebasisofthemodelabove,anewsafetycriterionofblastingvibrationeffectis
putforward,whichcanreflecttherelationbetweenthestructuralvelocityresponsemagnitudeunder
blastingloadstimulationandthefollowingparameters:structuralcharacteristics,amplitude,frequenciesincludingseveraldominantfrequencies,
durationandenergyproportionofblastingload.In
theend,bycombiningwithanactualengineeringcase,velocityresponseamplitudesarecalculatedby
thecomputationalmodelputforwardinthispaperandthetemporalanalysismethod,respectively.
Andthecomputationalresultsshowthatthiscomputationalmodelisfeasible.