平面钢屋架节点刚性次应力影响分析

Analysis of the Secondary Stress of Planar Steel Frames

应用有限元分析软件,对两种跨度下典型平面钢屋架节点刚性所产生的次应力进行了分析计算.对典型平面钢屋架采用了平面铰接模型、平面刚接模型Ⅰ以及平面刚接模型Ⅱ.分析了在普通荷载作用下钢屋架次应力的大小、分布规律以及影响次内力大小的主要因素,并初步探讨了次应力对钢屋架计算方法的影响.结果表明,钢屋架杆件的次内力随着杆件线刚度的增大而增大,随着屋架跨度的增大,次应力的影响也愈大,且次应力的影响不可忽略.该结论可为考虑次应力的钢屋架的设计提供参考.

The secondary stresses of typical planar steel frames due to the rigidity of panel points are calculated by the finite element analysis program.For comparison,three kinds of analytic models of typical planar steel frames are established: planar pin connected model, planar rigid connected model one and planar rigid connected model two.The level and distribution of the secondary stresses in the steel frames under common load is analysed,and the major factor influencing the secondary stresses is also analysed.The influence of the secondary stresses on the steel frames calculation method is discussed.Some conclusions are drawn that the secondary stresses of steel frame are increased with the increase of linear stiffness,that the influence of secondary stress is also increased with the increase of frame span,and that the influence of secondary stress can not be neglected.Some references are provided for the design of the steel frames considering the secondary stresses.