摘要:
结合在建的贵昆线六盘水至沾益段增建Ⅱ线扒挪块隧道开挖工程,采用动力有限元程序建立了3
维模型,对贵昆线狮子口隧道混凝土衬砌的质点振动速度以及应力分布情况进行了计算。计算结果表明,在
整个考察范围内,垂直方向振速峰值比其他2个方向上的振速峰值大,但在拱顶以及底板单元的主要拉伸应
力为水平方向,说明垂直振速并不能完全代表围岩的受力状况。在实际工程中,不仅要控制爆破振动速度,而
且对围岩的受力状况也要进行分析。计算最大振速为4.94cm/s,小于工程要求的5.00cm/s;拱顶最大拉伸
应力为0.54MPa,既有隧道混凝土衬砌没有受到破坏。
关键词:
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爆炸力学 /
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爆破振动 /
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爆破 /
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隧道
Abstract:
Basedonanactualtunnelexcavationproject,thethree-dimensionalfiniteelementmodelof
tunnelexcavationwassetup,andtheparticlevibrationandstressdistributionwereanalyzedatthe
existingadjacenttunnelconcretelining.Thecalculationresultshowsthatinthewholerangeofinvestigation,
theverticalpeakparticlevibrationisbiggerthanthoseintheothertwodirections,butthe
maintensilestressinthetunnelvaultcrownandbottomisinthehorizontaldirection,whichproves
thattheverticalpeakparticlevibrationcannottotallyrepresentthestressstateofrock.Inactualprojects,
theblastingpeakparticlevibrationshouldbecontrolled,andthestressstateofrockshouldbe
analyzedaswell.Themaximumpeakparticlevibrationcalculatedis4.94cm/s,whichissmallerthan
5.00cm/srequiredinprojects;themaximumtensilestressinthetunnelvaultcrownis0.54MPa,so
thetunnelconcretelineisnotaffected.