连续两次侧向冲击下格构式钢构件的力学性能

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中图分类号：O347;TU392.1 国标学科代码：13015 文献标志码：A

Abstract：The evaluationof protective performanceoptimizationofthedesignofbuilding structures under impactloading is akeyissueofonceinthefieldsofnationaldefense，civilengineering，otermilitarycivianuse.Laticecolumns areoftenusedasthemainload-bearingcomponentsinengineringstructuresareinevitablyimpactedbyother unintentional loads under engineering service environments. In this paper， 1 ： 2 scaled-down secondary impact tests were carried out on lattce columns along diferent impact directions with the same impact energy each time compared with single-impact laticecolumns under the same total energy toanalyze the force deformation characteristicsof the latice columnsundertheimpactloads.Then，basedontheexperimentallyverifiedfiniteelementmodel，acontinuousecondary impact simulation was carriedout on thefoo-foot attice column.The dynamic response ofte lattcecolumn subjected to two consecutiveimpacts with thesame total energywasobtained，theeffectsofdiferent energydistributions onthe impact force，residual displacement，residual kinetic energywereanalyzed.Theresultsshowthatunder thesametotalenergy，the displacement of latice columns under a single impact is greater than that of a secondary impact.The optimal energy distributionobtained bynumerical simulationcanreducetheresidual displacementof members impacted alongdifferent directions by about 12 % . When the lattice column is subjected to a larger proportion of energy for the first time or a smaller proportionofimpactenergyforthesecond time，thetotal energyabsorbedbythecolumn issmaler.Finaly，basedonthe results of tests numericalsimulations，the maximum impact velocityat which thedamaged column can withstasecond impact is proposed.Theresults ofthe studycan providea reference for the design method oflattce steel columns under such loading conditions.

Keywords： lattice columns; secondary impact; dynamic response; energy distribution

格构柱具有自重轻、抗弯抗扭性能好、稳定性高及空间布置更灵活的优点[1-2]，常作为工程结构中的主要承重构件，主要用于有重型吊车的厂房和大型公共建筑等场合。（剩余11225字）