城市连续钢箱梁施工预拱度研究

Research on Pre-camber of City Steel Box Girder Bridge

城市钢箱梁桥在施工中要设置施工预拱度,其值是在设计预拱度的基础上考虑很多因素影响,目前多凭经验设置。针对二阶段制造方式的预制架梁法施工,采用简化方法分析了体系转换、支架支座沉降、环口焊接收缩和昼夜温差4种主要因素对钢箱梁挠度的影响,总结了胎架预拱度和临时支架施工预拱度的设置方法,运用该法计算实际工程105m单箱双室钢箱梁桥的施工预拱度,与实际情况吻合较好。

It should set construction camber in the construction of steel box girder bridge,which considered many factors on the basis of camber of design,and made mainly by experience at present. On the two-phase manufacturing way of precast girder construction,this paper uses the simplified method to analyze influence of four main factors to the deflection of steel box girder,which are system transformation,settlement of stents and bearings,welding shrinkage on interface and temperature difference between day and night,and then come to the conclusion of setting method of jig camber and temporary support camber. Uses the method to calculate construction camber of 105 meter's single double room steel box girder bridge and is in accordance with the actual situation.