新型单弦杆平板网架整体后张拉成形研究(英文)

Research on shape forming of new single-chorded plan space truss by post-tensioning

首先提出一种合理的新型单弦杆平板网架结构模型,通过张拉带有预留缝隙的下弦杆中的内穿钢索,使平板网架整体张拉成空间球面网壳.然后推导出预测成形形状的理论公式,并利用有限元计算程序ANSYS,对不同有限元模型模拟其张拉成形过程.分析表明理论公式可以很好地预测网壳成形形状,与有限元计算结果吻合较好.其成形形状仅与预留缝隙值大小有关,可以忽略不同节点连接形式对成形形状的影响.

Abstract. A reasonable structural model of a new kind of single-chorded plane spatial truss is proposed. The whole plane spatial truss could be transformed to a spherical spatial shell through tensioning the inner steel cable which is pre-installed in the lower chord, and there are gaps reserved between each lower chord. Then, predicting formulas of forming shape could be deduced through theoretical model. ANSYS is employed to simulate the tensioning process for several kinds of finite element models. It is shown that theoretical formulas could perfectly predict forming shape of truss, which matches well with the calculating results of finite element models. The forming shape is only related to the reserved gap, whereas has little relation to different joint forms.