高速铁路连续梁三跨式双T构同步节段拼装施工技术

Construction Technology of Three-Span Double T-Structure Synchronous Segment Assembly for Continuous Beam of High Speed Railway

新建连徐高速铁路东海特大桥(32+48+32)m连续梁上跨大沙河,梁体为单箱单室、等高度箱梁,除合龙段现浇外其余梁体划分为40个预制节段。研究提出选择LHP56B型架桥机辅以移动式钢结构平台进行施工,创新采用三跨式双T构同步节段拼装施工技术,对称梁体节段拼装后,采用永久预应力钢束锚固形成悬臂梁,中跨现浇合龙。与目前常用的单T构节段梁满挂拼装施工技术和半联多节段悬臂胶拼施工技术相比,该项施工技术大幅降低了架桥机的节段拼装风险和过孔风险,可有效保证成桥线形,且施工更快速。

The(32+48+32)m continuous beam of the newly-built Donghai Super Major Bridge of XuzhouLianyungang High Speed Railway overpasses the Dasha River.The beam body is designed into a single-box and single-chamber box beam with equal height.Except for the cast-in-situ closure segment,the rest beam body is divided into 40 precast segments.In the study,it is proposed to select LHP56B bridge girder erection machine supplemented by mobile steel structure platform for construction,innovatively adopt the construction technology of three-span double T-structure synchronous segment assembly,and after the symmetrical beam segments are assembled,anchor the permanent prestressed steel cable to form cantilever beam and complete cast-in-situ closure of midspan.Compared with the construction technology commonly used at present for fullhanging assembly of single T-structure beam segments and semi-connected multi-segment cantilever glue assembly,this construction technology greatly reduces the risk of segment assembly and span passing of the bridge girder erection machine,which can effectively ensure the alignment of the bridge and accelerate the construction.