摘要
讨论了材料力学教材中某些强度及刚度问题的计算。研究结果表明:把销钉连接叠层梁作为静定问题来处理,有时会导致叠层梁的弯曲应力及销钉剪力计算存在很大的计算误差;第三强度理论与第四强度理论的最大计算误差为22. 49%;考虑剪切变形对梁弯曲的影响时,宜采用材料力学教材中能量法给出的梁中点挠度公式。因为,能量法给出的梁中点挠度公式不但计算简洁,而且计算精度也高。
Some calculation problems of strength and rigidity in the teaching material of Material Mechanics are discussed.The research results show that taking the laminated beam with pin connection as statically determinate problem,there sometimes is larger calculation error of bending stress and pin shear force in laminated beam,and the maximum calculation error is 22. 49% in accordance with the third and fourth strength theory. Taking into account the effect of the shear deformation on the bending beam,the deflection formula in beam midpoint based on the energy method in the teaching material of Material Mechanics is more suitable,and this is because there are simple calculation process and higher accuracy for the deflection formula in the beam midpoint based on the energy method.
引文
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