材料力学课件第五章弯曲内力

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4、(SlxFxxMlxFxF 0SFA左左FFA 右右SFSxFFlxM2RRqlFFBA lqFFABx)0(222)()0(2)(2RRSlxqxqlxxqxxFxMlxqxqlqxFxFAA )0(2)(SlxqxqlxF2SqlF 2SqlF +ql/2ql/2BlqFAxF)0(222)(2RlxqxqlxxqxxFxMA lqFABxF00 Mx，0, Mlx( )d0d2M xqlqxx2lx 822maxqlMMlx+82qll/2 lqFABxF+ql/2ql/282maxqlM2maxSqlF+82qll/2lFABCabFFlFbFA RlFaFB R xxlFABCabF

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6、 xx Mlxll)(lxa CMaMl左左 0M CMbMl右右Mal+MbllABCabFRAFRBM+/M lMal+MblABFlxlxlFFA)(R lFxFB RxlxlFxFMAC)(R 0ddxMC0)2(xllF2lx 2lx xlxlFxFMAC)(R FlM41maxxyq(x)FMxyq(x)FMFS(x)M(x)FS(x)+dFS(x)M(x)+dM(x)mmnnq(x)C .nxmmn dx02d)d(d )()( )(d)( 0 S xxxqxxFxMxMxMMCFS(x)M(x)FS(x)+dFS(x)M(x)+dM(x)mmnnq(x)C0dd 0SSS x)

7、x(q)x(F)x(F)x(FFy )(d)(dSxqxxF)(d)(dSxFxxM)(d)(dSxqxxF)(d)(dSxFxxM)(d)(d22xqxxMxFS(x)OxOM(x)(d)(dSxqxxF)(d)(dSxFxxM)(d)(d22xqxxMxFS(x)OxOM(x)(d)(dSxqxxF)(d)(dSxFxxM)(d)(d22xqxxMOM(x)x)(d)(dSxqxxF)(d)(dSxFxxM)(d)(d22xqxxMFCMC或或q0FMC)(SxF)(d)(dSxqxxF ( )( )2211SddxxxxFxq xx()()( )21S2S1dxxFxFxq xx()()