武汉天兴洲公铁两用长江大桥道碴槽板施工技术

Construction Techniques for Ballast Trough Slabs of Wuhan Tianxingzhou Changjiang River Rail-cum-Road Bridge

武汉天兴洲公铁两用长江大桥下层为两线客运专线、两线Ⅰ级货运线,铁路桥面采用道碴槽板与钢纵梁相结合的桥面结构,施工精度要求高。槽板预制采用钢模板,钢筋绑扎在胎架上一次成型,整体吊装定位,混凝土一次浇注成型;道碴槽板架设采取货运线从南向北、客运线从北向南两端相对同步架设方式,边架设,边后续结合。施工中重点控制道碴槽板的预制精度、混凝土的质量、道碴槽板的安装质量等。

The lower deck of Wuhan Tianxingzhou Changjiang River Rail-cum-Road Bridge is a railway bridge arranged with two tracks of passenger dedicated lines and two tracks of Grade I freight transportation lines. The deck was designed as a structure composited with ballast trough slabs and steel stringers and the accuracy requirements for construction of the structure was stringent. The ballast trough slabs were precast with steel formwork, the reinforcement for the slabs were bound well on the jig support in one time, lifted and set in place in integrity and the concrete was cast also in one time. The slabs were installed on the deck simultaneously for the freight transportation lines from the south end towards the north end while for the passenger dedicated lines, from the north end to the south end and as the slabs were installed, the slabs and the steel stringers were made composite. In the construction process, the precast accuracy, concrete quality and installation quality of the slabs were mainly controlled.