关键词: 薄壁方管, 轴对称动力屈曲, 平均撞击力, 塑性应力波, 弯曲刚度

Abstract:

Mechanism of axial dynamic buckling of thin-walled square was studied, and design method of axisymmetric deformation square was indicated, it was used mainly for design of energy-absorbing structures of subway anti-climbers. Dynamic load characteristics of axisymmetric dynamic buckling of thin-walled square were revealed, mathematical models of average impact force and plastic transverse, longitudinal waves were built, it was proposed that thin-walled square's deformation mode was decided by propagation velocity of the plastic stress wave and overall bending stiffness of thin-walled square, and it was explained that design of axisymmetric deformation square is easier than that of tube. Axisymmetric deformation square was designed according to certain safety requirements, energy-absorbing structures of anti-climbers can be designed in parallel by thin-walled squares of different thicknesses,materials and cross-sections. Mathematical models can guide design of square with axisymmetric deformation, can save a lot of manpowers, financial resources and time, and it has an important significance for engineering practice.

Key words: thin-walled square, axisymmetric dynamic buckling, average impact force, plastic stress wave, bending stiffness