This paper presents the tensile behavior of bolted circular flange connections that represent typical connectivity of leg members in a steel guyed lattice communication tower. A total of twelve specimens have been tested to failure under increasing monotonic tension. Each test specimen consists of a pair of circular flange plates (Φ178 mm), where each plate is welded to a solid circular bar. The flanges are bolted back-to-back using two high-strength bolts located 180º apart. The focus of the experiment includes the development of gaps between the upper and lower flanges connected with ASTM A325 bolts (Φ16 mm), increase in bolt forces, and prying action. The development of gaps between the flanges is significantly influenced by the size of leg members. The increase in the bolt force at failure is approximately 40%, relative to the initial preload of 110 kN. The maximum prying force is observed at the preload level and the prying force decreases gradually as the flanges are further loaded, indicating a complete separation of the upper and lower flanges. The widely used T-stub design equations conservatively predict the behavior of bolted circular flange connections. The proposed predictive equations agree well with the test data, especially near the failure of the bolts.

中文翻译：

---

承受拉伸载荷的圆形法兰螺栓连接的行为

本文介绍了螺栓固定的圆形法兰连接的拉伸性能，这些连接代表了钢格架式通讯塔中支腿构件的典型连接性。在增加的单调张力下，总共测试了十二个样品的破坏。每个试样由一对圆形法兰板（Φ178mm）组成，其中每个板都焊接到实心圆棒上。使用两个相距180º的高强度螺栓将法兰背对背固定。实验的重点包括与ASTM A325螺栓（Φ16毫米）连接的上，下法兰之间的间隙的发展，螺栓力的增加和撬动作用。法兰之间间隙的发展受支腿构件尺寸的影响很大。破坏时螺栓力的增加约为40％，相对于110 kN的初始预紧力。在预载水平观察到最大撬力，并且随着进一步加载法兰，撬力逐渐减小，这表明上，下法兰完全分开。广泛使用的T型短管设计方程式保守地预测了螺栓连接的圆形法兰连接的行为。所提出的预测方程与测试数据非常吻合，尤其是在螺栓损坏附近。