摘要：
银川滨河黄河大桥东水中引桥为双幅(5×80) m曲线连续钢-混组合梁桥,由开口钢槽梁和预制桥面板结合而成.桥位处施工场地受限,冬季长、冻土深.为实现冬季连续施工,该桥利用单侧场地,充分发挥钢-混组合梁的结构特点,采用无跨间支撑的整联横移技术进行双幅箱梁施工.在施工中,对地基进行冻结处理,在冻土上设预制扩大基础和钢管柱,形成快速拼装支架;利用双幅承台设横移支架和墩顶横向滑移装置,在顺桥向跨间无支撑状态下,将右幅钢梁整联横向滑移就位;采取了钢梁线形预设抛高、浇筑负弯矩区底板混凝土、设剪力钉及分步安装桥面板等综合措施,在无跨间支撑状态下将钢梁与预制混凝土桥面板结合,最终形成的钢-混组合梁结构满足设计目标线形与内力要求.%The east approach bridge of Yinchuan Binhe Huanghe River Bridge over water is comprised of the twin curved steel and concrete continuous composite girder bridges with span arrangement (5×80) m and is composited by the steel channel girders and precast concrete deck slabs.At the location of the bridge, the construction site is restricted, the winter lasts long and the frozen soil is deep.To realize the uninterrupted construction of the bridge in the winter, the construction site on the one side of the bridge was used, the structural characteristics of the steel and concrete composite girders were fully brought into play and the twin box girders were then constructed, using the technique of the transverse sliding of each full continuous unit with no supports arranged amidst the spans along the bridge.In the specific construction, the ground frozen soil was firstly handled, the precast spread foundations were set in the soil and on the foundations, the steel pipe columns were installed to rapidly form the supports for the assembling scaffoldings.The scaffoldings for the transverse sliding and the transverse sliding devices at the pier tops were arranged, using the twin pile caps.The full continuous unit of the right part of the steel channel girder was transversely slid in place under the condition of no supports.The comprehensive measures, such as the presetting of the initial height for the alignments of the steel channel girders, casting of the concrete for the bottom slabs in the hogging moment areas, setting of the shear studs and installing of the deck slabs in step, were taken.The steel channel girders and the concrete deck slabs were made composite under the condition of no supports and the final installed steel and concrete composite girders could satisfy the requirements of the designed target alignments and internal forces.
