双层柱面网壳需考虑行波效应的最小平面尺寸

Minimum Plane Dimensions of Double-Layer Cylindrical Latticed Shells Considering Traveling Wave Effect

为了探究大跨空间结构需考虑行波效应的最小平面尺寸,采用时程分析法对不同平面尺寸双层柱面网壳进行多点输入与一致输入的对比分析,研究了一致输入下地震内力峰值不小于10 kN且行波效应系数不小于1.1的特殊杆件的分布规律。结果表明:特殊杆件主要出现在上弦纵杆中,改变结构平面尺寸会影响特殊杆件的数量和比例;当跨度达到60 m且长度达到90 m时,上弦纵杆中特殊杆件占比达到10%,继续增大结构长度会使特殊杆件比例增大,继续增加结构跨度则会使特殊杆件比例减小。可见,跨度60 m与长度90 m是需对此类结构上弦纵杆考虑行波效应的最小平面尺寸。

In order to research the minimum plane dimensions of long-span spatial structures that considering traveling wave effect,the time-history analysis method was used to investigate the differences among double-layer cylindrical latticed shells with different plane dimensions under multiple-support excitation and single excitation by discussing the distribution of special members whose peak internal forces under single excitation were greater than 10 kN and traveling wave effect coefficient were greater than 1.1.The results showed that changing the structural span or length would lead to the amount or percentage of special members changed,which were concentrated in longitudinal members at the top chord,the percentage of special members was up to 10%when the span of reduce the percentage of special members reached 60 m and the length reached 90 m.Increasing the lergth of structure would increase the proportion of special members,while increastring the span would decrease the proportion.It was concluded that 60 m of the span and 90 m of the length were the minimum plane dimensions of this kind of structure that considering the traveling wave effect of longitudinal members at the top chord.