材料力学第24讲 组合变形 8-1、8-2

1、 组合变形实例工程实例hg g = =+ + += =+ +1、忽略纵向力的附加弯矩(大抗弯刚度)2、忽略剪力和弯曲切应力 0 AFN zzIyM zzNIyMAF 02FFN 41maxlFM xxFN图图M图图F2F1/4 AFNt WMbmax AFt2 WlFWMb41max WlFAFbtt412max - max maxtt maxcc 拉(压)弯组合起重机受力如图，W=8kN。若已知=100MPa，试选择工字钢的型号。 33363max120101210100.1012cmmPamNMW【2】同时考虑轴力与弯矩的作用：】同时考虑轴力与弯矩的作用：最大压应力与许用应力接近【相差不到

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