结合双主梁斜拉桥节段拼装与构件拼装比较

Comparison of Segmental Assembling and Component Assembling for Cable-Stayed Bridge with Twin Composite Main Girders

结合梁斜拉桥加劲梁施工可采用节段拼装法和构件拼装法。节段施工法为在预制场地内先把钢结构、混凝土结构进行结合,形成结合节段后进行运输、吊装安装;构件施工法为钢结构与混凝土结构在吊装前均是独立构件状态,在构件依次吊装、安装到位后形成结合截面共同受力。对2种施工方法进行施工难度、风险、质量、工期,材料用量等方面的比较,构件拼装法施工难度小、施工措施简单、风险小,但施工周期长、钢结构材料用量多;节段拼装法施工难度大、施工措施复杂、风险大,但施工周期短、钢结构材料用量省。2种施工方法有各自的特点和优势,具体工程应根据实际情况选择采用。

The main girder of the composite girder cable-stayed bridge can be erected either by the construction methods of segmental assembling or component assembling,of which the method of the segmental assembling is that the steel and concrete structures are firstly composited in the precast yard and after a composite girder segment is formed,the segment is delivered to the bridge site where it will be then lifted and assembled while the method of the component assembling is that before the lifting and assembling,both the steel and concrete structures are the independent ones and the structures will be respectively lifted and assembled in place and will be then composited to result in a composite cross section that will jointly carry load.The construction difficulties,risks,quality,working time schedules and material usage of the two kinds of the construction methods are compared and it is concluded that for the method of the component assembling,the construction difficulties are less,the construction measures are simple and the construction risk is little,but the working time schedule required by the method is long and the steel material usage is great.For the method of the segmental assembling,the construction difficulties are more,the construction measures are complicated and the construction risk is great,but the working time schedule required by the method is short and the steel material usage is saving.The two methods have their own characteristics and advantages,which should be appropriately selected for a specific project according to the actual situations.