(1 南京工业大学土木工程学院， 南京 211800；  2 浙江省电力设计院， 杭州 310012)

［摘要］特大型钢管结构（如大跨越输电铁塔等）主材内力及直径均非常大，钢管接长后采用传统刚性法兰连接不能满足承载力要求且不经济。在钢管内外侧均设置连接螺栓，形成钢管内外法兰。并针对钢管填充混凝土与否，设计并制作钢管内外法兰及钢管混凝土内外法兰试件，开展2种内外法兰抗弯承载力性能试验、有限元模拟分析和抗弯旋转轴计算理论研究，考察其承载力特性、传力机理及旋转轴位置。分析加载过程中连接螺栓、钢管及混凝土应变的发展情况，得到法兰啮合面旋转轴位置及内外螺栓内力分布规律。研究表明，钢管混凝土内外法兰受弯时可以避免钢管发生局部屈曲，提高了法兰节点整体抗弯刚度； 且随着荷载的增大，法兰板张开，混凝土开裂，螺栓发生颈缩破坏。钢管内外法兰及钢管混凝土内外法兰抗弯承载力设计时，连接螺栓旋转轴位置分别可取距离管中心0.6R，0.8R(R为钢管半径)。

［关键词］钢管混凝土结构； 内外法兰； 抗弯承载力； 旋转轴； 连接螺栓； 法兰连接

中图分类号：TU392-3， TU317-1文献标识码：A文章编号：1002-848X(2021)02-0071-07

Study on the influence of concrete filled steel tube on the flexural bearing capacity of inner and outer flange joints

CHEN Qian1, ZHANG Kaixuan1, GUO Yong2, ZHANG Dachang1

(1 College of Civil Engineering, Nanjing Tech University, Nanjing 211800, China；2 Electric Power Design Institute of Zhejiang Province, Hangzhou 310012, China)

Abstract:The internal force and diameter of the main material of extra-large steel tube structures(such as large-span transmission tower, et al.) are very large. When the steel tube is lengthened, the traditional rigid flange connection can not meet the requirement of bearing capacity and is not economical. Connecting bolts were set on the inner and outer sides of the steel tube to form the inner and outer flanges of the steel tube. According to whether the steel tube was filled with concrete or not, the inner and outer flanges of steel tube and the inner and outer flanges of concrete filled steel tube were designed and manufactured. Carry out two types of inner and outer flange anti-bending bearing capacity performance test, finite element simulation analysis and theoretical research on bending rotating shaft calculation to investigate its bearing capacity characteristics, force transmission mechanism and rotating shaft position. The development of the strain of connecting bolt, steel tube and concrete in the process of loading was analyzed, and the position of the rotating shaft of the flange connection interface and the internal force distribution of the internal and external bolts were obtained. The results show that the inner and outer flanges of concrete filled steel tube avoids the local buckling of the steel tube when the flange is bent, and improves the overall bending rigidity of the flange joint. And with the increase of load, the flange plate is opened, the concrete cracks, and the bolt is necked damaged. When designing anti-bending bearing capacity of the  inner and outer flanges of steel tube and the inner and outer flanges of concrete filled steel tube, the rotating shaft of bolt is suggested be 0.6R and 0.8R (R is the radius of the tube) distant from the centerline of the tube.

Keywords:concrete-filled steel tube structure; inner and outer flange; anti-bending bearing capacity; rotational axis; connecting bolt; flange connection

*浙江舟山500千伏联网输变电工程大跨越研究专题项目(ZT2016-05)。

作者简介：陈前，硕士，Email：44794951@qq.com； 通信作者：张大长，博士，教授，Email：dczhangchina@163.com。