黄冈公铁两用长江大桥钢桁梁杆件制造关键技术

摘要

The main bridge of Huanggang Changjiang River Rail-cum-Road Bridge is a steel truss girder cable-stayed bridge with double pylons and double cable planes.The chord and web members of the main truss of the bridge were designed as the ones of parallelogram sections.To guarantee the manufacturing quality of the members,the key techniques for the manufacturing were studied.The precision of the geometric dimensions of the members was guaranteed by the techniques of controlling the precision of the inclined angle grooves of the welded edges,fine adjusting the diagonal line dimensions of the diaphragms (controlling the angles of the end openings) and assembling the members on the special jig supports.The precision of the anchor tube positioning was guaranteed by the techniques of converting the spatial positioning dimensions of the anchor tubes into the plane positioning dimensions and controlling the installing,welding procedures of the anchor boxes and the installing precision of the anchor tubes.The assembling quality of the steel truss girder was guaranteed by the techniques of testing the precision of the hole groups at the inclined web member joints by the special testing templates for the web member joints.Practice proves that the key techniques applied to the manufacturing of the members effectively tackle the control problems of the members of parallelogram sections and guarantee the manufacturing precision of the steel truss girder of the bridge.%黄冈公铁两用长江大桥主桥为双塔双索面钢桁梁斜拉桥,其主桁弦杆和腹杆采用平行四边形截面.为保证主桁平行四边形截面杆件的制造质量,对其制造关键技术进行研究.通过控制杆件焊接边斜角坡口精度、微调隔板对角线尺寸(控制端口角度)、应用专用胎架组拼杆件的技术保证杆件形位尺寸的精度.通过将锚管空间定位尺寸转化为平面定位尺寸、控制锚箱安装及焊接工序、控制锚管安装精度的技术保证锚管定位精度.应用专用的斜腹杆接头检测模检测斜腹杆接头处孔群精度的技术保证钢桁梁拼装质量.实践证明所采用的钢桁梁杆件制造关键技术有效地解决了该桥主桁杆件平行四边形截面控制难点,保证了钢桁梁的制造精度.