| 2. | Fabrication of the box beam is divided into such parts as reinforcement , formwork , concreting , prestressing , moving and storing of beam , pipe grouting under pressure , end sealing of the beam , water - proof layer on the bridge surface system , protective coating etc . the paper makes description of effective box beam construction technology and workmanship which can be adopted in other projects , such technologies as : manufacturing and fixing of reinforcement , steel reinforcement fixing baseplate , web plate and top plate respectively and lifting the steel skeleton into form , requirements of design and manufacturing and way of utilization for dismantling - erection type formwork and hydraulic formwork , optimization of concrete ratio , concrete pouring process of two ends of beam in priority over the middle , in sequence of first baseplate followed by web plate and top plate at last , concrete pouring in inclined section and in horizontal layer , concrete vibration mainly by external vibrator in assistance with internal vibrator , methods and regulation for steam curing of concrete , dual controls over stress and strain to ensure quality of prestressing workmanship , construction method of effective beam moving by heavy - weight special moving facility , some regulations and key notes about construction of grouting under pressure , beam ends sealing , water - proof layer on the bridge surface system , protective coating
箱梁制造由钢筋工程、模板工程、混凝土工程、预应力工程、移存梁工程、孔道压浆工程、梁体封端工程、桥面防水层和保护层工程等施工环节组成。文中介绍的采用胎具制作和绑扎钢筋，分底腹板和顶板分别绑扎并吊装钢筋骨架入模；拆装式和液压式两种模板的设计、制作要求和使用方法；综合考虑、优化混凝土配合比，混凝土灌注从两端至中间、先底板、后腹板、再顶板的施工顺序和斜向分段、腹板水平分层、附着式振捣为主、插入式捣固为辅的施工工艺，蒸汽养护的方法和规定；应力应变双控制确保预应力施工质量的施工技术；采用重物移运器有效移梁的施工方法；压浆、封端、桥面防水层和保护层施工的一些规定和注意事项等都是对箱梁制造行之有效的施工技术和施工方法，并可为以后类似施工作借鉴。 |
