[提要]单弦杆平板网架由于无下弦杆，因而具有平面外抗弯刚度较低的特点。利用此特点，在网架局部下弦节点间设置带预留缝隙的张拉下弦杆，通过后张拉下弦杆内的张拉钢丝，平板网架可以较容易地张拉变形为具有多种外观形状的空间曲面结构，如：桶拱、穹顶、马鞍拱。这种网壳成形方法不需要传统空间网壳拼装过程中所需的脚手架及重型吊车，因而降低了施工造价，工程应用价值很好。在前人研究的基础上，提出了一种新型的后张拉整体成形穹顶的单弦杆平板网架模型，成形试验研究证明了它的合理性和可行性。

[关键词]单弦杆平板网架 后张拉 穹项 桶拱 马鞍拱

Abstract:The single-chorded plane space truss have the low flexural rigidity out of plane because of lacking bottom chord. Using this feature, the single-chorded plane space truss which have the bottom tensioning-chord can easily form into curved space trusses with zero, positive, or negative Gaussian curvature, for example vault, dome, hyper, by means of tensioning wire which lie in the bottom chord. This novel post-tensioning method eliminates the need to use scaffolding or heavy cranes for construction, so it reduces the cost of construction and have the well application value. This paper advances a new single-chorded plane space truss mode which can form dome by means of post-tensioning on the base of predecessors study, though the test study, the validity is proved.

Keywords: single-chorded place space truss; post-tensioning; dome; barrel vault; hyper