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应用有限元软件ANSYS/LS-DYNA建立50m跨度的单层联方球面网壳及其相应的弦支网壳的有限元模型并进行数值模拟分析,得到联方单层球面网壳及其相应弦支网壳的冲击力、位移及杆件应力随着冲击速度和冲击体重量变化的时程曲线变化规律.通过分析表明联方网壳及其弦支结构的冲击过程相类似,可以分为冲击阶段、稳定相持阶段和衰减阶段3个阶段;网壳杆件突然断裂会导致冲击力发生突然的变化;弦支结构相对于联方单层网壳而言,在相同的冲击速度和冲击重量的作用下,弦支结构可显著减小网壳的最大位移,增加网壳的抗冲击能力;弦支结构索力的增加可适当减小冲击产生的位移,但减小效果有限;径向杆件和环向杆件的冲击应力距离冲击点越远,冲击应力峰值及残余应力也越小.
The finite element model of 50m-span single-layer spheric reticulated dome and its corresponding chordal shell was established with the finite element software ANSYS / LS-DYNA and the numerical simulation was carried out to obtain the single-layer spherical reticulated shell and its corresponding chord The variation of the impact time, the displacement and the bar stress of the reticulated shell with the change of the impact velocity and the weight of the impact body shows that the impact process of the reticulated shell and its chordal structure are similar and can be divided into impact Stages of phase stability and phase of decay three stages; a sudden rupture of the shell member will lead to an abrupt change in impact; chord structure relative to the monolayer reticulated shell at the same impact velocity and impact weight Under the action, the chord structure can significantly reduce the maximum displacement of the reticulated shell and increase the impact resistance of the reticulated shell. The increase of the cable force can reduce the displacement caused by the impact, but the reduction effect is limited. The radial rod And the impact of the ring to the impact stress away from the point, the peak value of impact stress and residual stress is also smaller.