四、有残余应力并有初始缺陷的轴心压杆(或有残余应力的偏心压杆)的理论计算上一节的分析是指理想直杆而言。实际上,钢压杆的屈曲强度除受残余应力影响外,总是受几何缺陷的影响的。钢压杆的几何缺陷包括横截面尺寸和特殊性的偏差、初弯曲和初偏心等。在进行压杆理论分析时,一般选用初弯曲为半个正弦波形,其中点矢高为L/1000,作为代表性的几何缺陷。然后考虑初弯曲和残余应力的共同影响 IV. THEORETICAL CALCULATION OF AXIAL COMPRESSION LENGTH WITH RESIDUAL STRESS AND INITIAL DEFECTS (OR EMBRICIAL PRESSURE BARS WITH RESIDUAL STRESS) The analysis in the previous section referred to ideal straight bars. In fact, the buckling strength of steel compression rods is always affected by geometric defects, except for the residual stress. The geometrical imperfections of steel struts include variations in cross-sectional dimensions and particularities, initial bending and initial eccentricity. In the theoretical analysis of the compression rod, the initial bending is generally selected as a half sinusoidal waveform, where the dot height is L/1000, which is a representative geometric defect. Then consider the combined effects of initial bending and residual stress