绍兴则水牌大桥总体设计

Overall Design of Zeshuipai Bridge in Shaoxing

绍兴则水牌大桥主桥采用跨径布置为(65+120)m的独塔斜拉桥,塔墩梁固结。桥塔为由双肢塔柱、上塔头锚固区、后斜杆组成的三角形斜塔结构,其中塔柱采用“田”字形矩形多腔钢-混组合结构,钢箱内壁布置PBL加劲肋和焊钉混合型连接件,腔内灌注高性能混凝土;上塔头锚固区连接左右塔柱联合受力,主要承受边跨斜拉索及后斜杆集中力局部作用;后斜杆承担轴向拉力。边跨主梁采用整体式混凝土箱梁,主跨主梁采用分离式钢箱梁,钢-混结合面位于主跨距理论分跨线4.5 m处。斜拉索采用标准抗拉强度1860 MPa高强度低松弛环氧喷涂钢绞线,扇形布置在桥梁中央区域,塔端采用耳板销轴式锚固,梁端采用钢锚箱锚固。该桥桥塔采用分节拼装矩形多腔钢箱、逐节泵送内部高性能混凝土的工业化智能建造方法,边跨混凝土主梁采用现浇施工,主跨钢箱梁采用节段拼装施工。有限元计算结果表明,该桥组合桥塔、主梁、斜拉索受力均满足规范要求。

The main bridge of Zeshuipai Bridge in Shaoxing is a cable-stayed bridge with two spans of 65 and 120 m.The triangular inclined pylon consists of double-leg column,upper pylon head anchorage zone and rear inclined strut.The pylon column is a steel-concrete composite structure of multi-cell rectangular cross-section.PBL connectors and studs are embedded in the inner walls of the steel box of the pylon column,and the steel box is filled with high performance concrete.The anchorage zone in the upper pylon head shares loads with the left and right pylon columns,mainly the stay cable forces in the side span and concentrated force of rear inclined strut,and the rear inclined strut carries axial force.The superstructure in the main span consists of split steel box girders,with a steel-concrete joint surface in the main span,4.5 m to the theoretical span division line.The stay cables,arranged in fan planes in the central median,are formed of high-strength,low-relaxation,epoxy-coated steel strands with nominal tensile strength of 1860 MPa,anchored to the pylon by lug plates and to the deck by steel anchor boxes.The multi-cell rectangular steel pylon segments were installed and filled with high-performance concrete segment by segment.The side span was cast in situ,and the steel box girders in the central span were assembled at bridge site.The finite element calculation demonstrates that the mechanical properties of the pylon,hybrid superstructure and stay cables meet the requirements.