国家体育场焊接方管桁架双弦杆KK节点设计研究

结合国家体育场大跨度钢结构设计,提出任意角度相交焊接方管桁架双弦杆KK节点的几何构型方法,可用于各种复杂角度的腹杆汇交、弦杆呈折线形、弦杆侧壁与腹杆侧壁不垂直等多种情况,适用范围较大。通过调整节点域板件的角度,改善其构造的合理性。综合采用调整板厚、设置加劲肋等措施,提高节点的承载力,实现“强节点”的设计理念。双弦杆KK节点的缩尺模型试验表明,试件的应力分布与有限元计算非常接近,节点具有较大的安全储备。

Design and research of double-chord KK-connections of welded thin-wall box-section truss of the National Stadium

Based on the design of the large-span roof structure of the National Stadium,the geometric configuration of double-chord KK-connections of the largesize welded thin-wall box-sections is proposed in this paper.This method can be widely applied to complex situations where the diagonals with various angles meet,chords are straight line between adjacent connections or the walls of chords are not perpendicular to that of diagonals,etc.The angles between plates of the connections are adjusted to make the force transfer more reasonable.The bearing capacity of the connections is improved by adjusting plate thickness and arranging stiffeners.As a result,the design princile of "strong connections" can be realized.In addition,the scaled-model test is conducted to validate the reliability of the connections.The results show that the stress distribution of the specimen is consistent with that of the finite element analysis,and the estimation of the bearing capacity for the KK-connections is on the safe side.