细长压杆失稳时最大挠度的确定

针对国内工程力学教材普遍认为细长压杆失稳变形挠曲线线性化方程中的挠度值不确定的错误观点，指出其对细长压杆失稳变形挠曲线线性化方程推导存在误区，以两端铰支细长压杆为例，建立了其失稳变形挠曲线线性化方程后，又考虑了压杆失稳后两端截面形心产生轴向位移参数，通过消参，确定了细长压杆失稳时最大挠度值。结果表明：压杆失稳后两端截面形心产生轴向位移以及临界压力的确定这两个条件缺一不可才能在线性化下确定细长压杆失稳时最大挠度值，挠度值的大小与轴向压力直接有关。

The Maximum Deflection Determination of Instability for Slender Columns

Engineering mechanics teaching materials in domestic are generally accepted the fault idea that the deflection value of slender compressive bar buckling deformation flexural linearization equation is uncertain, the auther points out the buckling of slender compressive bar deformation flexural linearization equation is derived incorrectly .Taking both ends hinged slender compressive bars as an example, after established its flexural buckling deformation linearization equation, and then considering axial displacement parameters compressive bar instability on both ends of the central section, through eliminating the parame-ter, the maximum deflection of instability slender compressive bar is determined .Results show that axial displacement of the compressive bar instability on both ends of the central section and the critical pressure have necessary conditions to determine the maximum deflection value of slender compressive bar under the linear instability, the deflection value is directly related with the size of the axial pressure.