铜陵公铁两用长江大桥为五跨连续钢桁梁三索面斜拉桥，钢桁梁采用板桁结合形式，由3片主桁、上层正交异性公路板式桥面、下层正交异性铁路钢箱桥面及横联构成。钢桁梁采用整体焊接式桁片结构，每2个节间的主桁上、下弦杆，斜杆，竖杆通过整体节点焊接成桁片上桥安装。为验证制造工艺和精度并指导实桥施工，选取3．5个连续节间钢桁梁在工厂内一次完成立体试拼装。由于主桁桁片采用水平拼装制作工艺，采用800 t龙门吊机2×200 t吊钩提升加横移对桁片进行90°转体翻身后试拼装。试拼装过程中设置了抗推拉刚性斜撑增强桁片与铁路桥面的稳定性；在斜杆件加垫片，通过调整间隙控制桥梁预拱度。试拼装过程中设置了测量控制网，检测结果满足设计和验收标准，达到了立体试拼装目的。%The Tongling Changjiang River Rail‐cum‐Road Bridge is a five‐span continuous steel truss girder cable‐stayed bridge with three cable planes .The steel truss girder is the combined or‐thotropic steel plates and steel trusses structure ,containing three main trusses ,the upper ortho‐tropic steel plate deck for vehicles ,the lower orthotropic railway steel box deck and lateral brac‐ings .The steel truss girder is a integrally‐welded truss structure ,the upper and lower chords ,di‐agonal struts and vertical struts of the main trusses in every two blocks are welded by integral nodes to be truss block for assembling on the bridge .In order to verify the manufacturing tech‐nique and precision and to direct the construction of the real bridge ,the steel truss girder in 3 .5 continuous blocks were selected to conduct one‐time trial vertical assembly in the factory .The main truss blocks were fabricated by the horizontal assembling technique ,the 800 t overhead lift‐ing gantry with two lifting hooks of 200 t was adopted to lift and horizontally move the truss blocks and complete their 90°rotation and turning ,and then conduct the trial assembly .During the trial assembly ,the rigid diagonals resisting pushing and pulling forces were added to strengthen the stability of the truss blocks and the railway bridge deck .At the inclined members ,shims were wedged to control the precamber of bridge via adjusting the spacing .The survey control network was programmed as well during the assembling process ,the results of the inspection meet the de‐sign and acceptance standard ,achieving the goal of vertical assembly .
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