宁波市湾头大桥拱肋弦杆制孔工艺

宁波市湾头大桥主桥是3跨连续钢桁架拱桥,主桥拱肋由2片桁架和6道风撑组成,桥面系为采用主梁、横梁、纵梁的框架结构体系。拱肋杆件的曲线线形、构件之间连接关系复杂、部分构件超高、超宽、超长等是该桥的主要特点和难点。针对宁波市湾头大桥的结构特点,对拱肋上下弦杆在制造过程中合理采用杆件整体划线制孔、以直代曲等工艺,解决单个拱肋杆件孔群精度以及整个曲线拱线形等难题,取得良好效果。

DRILLING TECHNOLOGY OF ARCH RIB CHORD FOR NINGBO WANTOU ARCH BRIDGE

Ningbo Wantou Bridge is a three-span continuous steel truss arch bridge. Whose arch rib of the main bridge is composed of 2 trusses and 6 bracings; and the floor system is a frame consists of the main beams, crossbeams and longitudinal ones. Main features and difficulties include curve arch ribs, complex relationship between the components, some ultra-high, extra-wide and overweight elements etc. This paper introduces the technology of marking line and drilling of a whole element, using beeline instead of curve for the upper and lower chords of Ningbo Wantou Arch Bridge. The problems including the precision of hole group for single chord and whole curve linetype are solved, the relationship between the components is guaranteed, by which excellent effects are obtained.