1、稳定平衡稳定平衡不稳定平衡不稳定平衡16-1 16-1 压杆稳定的概念压杆稳定的概念临界状态临界状态临界压力临界压力:Fcr过过 度度对应的对应的压力压力)()(xwFxM22d)(d)(xxwEIxMEIFk20)()(222xwkdxxwdEIFk20)()(222xwkdxxwdkxCkxCxwcossin)(210)()0(lww0sin,012klCC0sin,012klCCkxCkxCxwcossin)(210sinklnkl,.)2,1,0(nlnk,.)2,1,0(222nlEInFEIFk2,.)2,1,0(222nlEInF22crlEIF22cr)2(lEIF 22cr)
2、5.0(lEIF 22cr)7.0(lEIF 22crlEIF 22cr)2(lEIF 22cr)(lEIF两端铰支两端铰支一端固定一端自由一端固定一端自由两端固定两端固定一端固定一端铰支一端固定一端铰支2123hbIy4443mm1048mm12409044433mm10243mm12904012bhIzzyII22cr)(lEIF37.86kN37860N N)25002(1048102002432mm60 bhmm10108mm126012443bhIIzy85.19kN85187NN)25002(1010810200)(243222crlEIFAlEIAF22crcr)(AiI222c
3、rcr)(ilEAF22crcr)(ilEAFil22crEilP22EP2EP2PEPP1001020010620692PGPa206EMPa200Pba cr材料（材料（s b）abQ235 s=235MPa b235MPa 3041.12优质碳钢优质碳钢 s=306MPa b471MPa 4612.568硅钢硅钢 s=353MPa b510MPa 5783.744铸铁铸铁332.21.454松木松木28.70.19ba crscrbass6.6112.1235304s:A551l:B9.477.0l:C5.429.0lpp2E861028010210692sbas2.43586.2350
4、4614di il62454700162crbaMPa302MPa62568.2461478.71kNkN10)1045(4103013236crcrAFmm56.86mm273213142731422DdDi63.13856.86150008.0ilMPa79.105MPa63.1381020623222crE2423kNkN10213273479.105322crcrAF9691kNkN242344crmaxFFT32.6956.8675008.020726kNkN102132734)32.6912.1304(4)(4322maxAbaFT14.2/maxmaxTTFF16-4 16-4 提高压杆稳定性的措施提高压杆稳定性的措施
