4521201511BuildingStructureVol.45No.21Nov.2015*12113114002310058SAP2000。12。。TU391A1002-848X201521-0047-05ApplicationvalueanalysisofhighorderbucklingwaveofframeJinBo1TongGenshu2ZhengJunhua11HangzhouPolytechnicCollegeHangzhou311400China2SchoolofArchitecture&EngineeringZhejiangUniversityHangzhou310058ChinaAbstractThebucklinganalysisofafour-layerandthree-spansteelframewithoutsomecolumnsintoplayerwascarriedoutbyusingthetraditionalcalculationlengthcoefficientmethodtocalculatethelateralresistancestiffnessofthelayer.ThecomparisonofthelateralresistancestiffnessbytraditionalmethodandbytheSAP2000softwarewascarriedout.Resultsshowthattworesultsareclosewhentheratiooftheshearforceofeachlayerbythehorizontalloadisequaltothattheratioofthelateralresistancestiffnessofthelayerbycriticalloadmethod.Theoverallbucklinganalysisofthesteelframewascarriedoutandthefirstbucklingmodeispointedouttobethebucklingofweaklayerandthesecondandhigherbucklingmodescannotbeusedbecausetheycannotreflecttheconstraintofframebeamtoframecolumncorrectly.Lackingofsomecolumnsintoplayerleadstoincreaseofaxialforceinroofbeamdecreaseofcriticalloadandthedecreaseordisappearanceoftherotationconstraintactionofroofbeamtoframecolumnwhichneedstobeconsideredincalculationofcalculationlengthcoefficientofcolumnintoplayer.Keywordsbeamwithvariablecross-sectioncalculationlengthcoefficientmethodmatrixdisplacementmethodbucklingfactorlateralresistancestiffnesscriticalload*20100333T25Y201122425Y201223824。Emailjb@mail.hzaspt.edu.cn。012。、7、。×70m×28m7m9109m70m×28m3.5kN/m2。SAP2000。SAP2000。1μμ=7.5K1K2+4K1+K2+1.527.5K1K2+K1+K槡21K1K2、。12015。nSFSF=∑nj=1αjπ2EIcjμ2jh3j2EIcjjhjjμjjαj2。αjαj=1+12π2-11+3K11+3K2K1K2+4K2-K121+2K1+K2+3K1K2231~1.216。1。μi'μi'=π2EIciSFh3i∑nj=1αjPjPi槡4SFPiPjijPj/Pi。4μi'SF2。μi2SF。SF。SF。2SF4μi'。21。1~4Ix8.46×108mm4123.47×108mm432.52×108mm41~3Ix6.253×108mm4、6.333×108mm42.334×108mm4。。4Kz1Kz=1K11-2s2s·1K12+s2s2·1K22+13ib25K11K12K22K11=3i11R0.21K12=-6i11R0.441K22=3i11R0.7121R1=I10I11i11=EI11s1I10I11s1s2s=s1+s2ib2ib2=EIb2/s2Ib2。s1=4667mms2=9333mmR1=0.369K11=6.868×1011N·mmK12=-1.081×1011N·mmK22=4.120×1011N·mm3ib2=1.545×1011N·mmKz=1.505×1011N·mmKz1。1K1K2μαPcr/kNαPcr/hP/kNμi'120.00.2031.49221.14825550.25.3321321.071.87120.2030.1852.23821.00616962.13.791928.022.44030.1850.1852.28121.00516330.13.648530.762.46740.1850.0652.77221.00711051.92.474125.892.772120.00.9411.18221.12816708.43.4262128.770.94420.9410.9911.34921.05219160.64.4801413.831.26730.9912.3541.24721.08216295.63.919703.131.170αPcrPh。12.1K1K21μPcr。4μi'1。11。。210.9441.0844521.。2.2。、。2SFμ。221234SFμ17.51616.54215.1344.94811111/kN/m17.34614.83510.8726.005SFμ1.011.1151.3920.82424321/kN/m19.01615.56111.7644.768SFμ0.9211.0631.2861.038317.314.38.881/kN/m18.71816.43713.512.048SFμ0.9361.0061.122.41643.543.343.061/kN/m17.87815.65113.8734.105SFμ0.981.0571.0911.20511123344442。2、14。2~434。4。。2212~4。11。33。。44223434。21。33、+。3112.25215.42512.2525.9%。213243。1、2、3、4。3。31234∑Pj/kN6899.74683.72467.78251.78202∑Pcrj/kN84517.272245.465251.322103.92326∑Pcrj/∑Pj12.2515.4326.4487.7911.5∑Pcrj'/kN89905.371253.362718.310174.1—∑Pcrj'/∑Pj13.0315.21325.41540.409—∑Pcrj″/kN98123.266608.935095.33580.7—∑Pcrj″/∑Pj14.2314.2314.2314.23—+202kNH450×200×6/1028mPEmin614.6kN2458.4kN。202kN3.0412.17942015。+χ。SAP20002。21114.23113。14.233112.2512。23215.43112.2525.9%1212。1343412。134。2218.50。3。K2≤0。4319.91K2=055.1919.91。19.91。542122212。6567345.642333。34。34。4。411.5440.40420.5×11.5+40.4=25.951-χP4PEmin=1-25.95×2024×614.6=-1.13<044。43。442∑Pj4/∑Pcrj4∑Pj3/∑Pcrj3+∑Pj4/∑Pcrj46。、。440K2=0。3∑Pcrj'。440.4093。231。054521.2233。“”2d。41“/”。21。。3、。4。43.55.817。1GB50017—2003S.2003.2.M.2005.3.J.2004641-8.4.J.2004649-14.15