新建南广铁路西江特大桥钢箱提篮拱架设方案比选  

Comparison and Selection of Erection Scheme for Steel Box Basket Handle Arch of Xijiang River Bridge on Newly-Built Nanning-Guangzhou Railway

作　　者：汪芳进 

机构地区：[1]中铁大桥局股份有限公司设计分公司,湖北武汉430050

出　　处：《桥梁建设》2013年第6期117-121,共5页Bridge Construction

摘　　要：新建南广铁路西江特大桥为主跨486m的中承式钢箱提篮拱桥,拱肋钢箱最大断面尺寸为15.0m×5.1m,内倾角为4.8°。针对该桥结构特点和桥址处的地质条件,结合工程经验,提出'边段竖转+中段提升'和'缆索吊机+扣挂法悬臂拼装'2种架设方案,通过技术可靠性、工期和经济性等方面的综合比选,选择后一种方案。该方案中,锚碇采用分散布置'集群式'预应力岩锚,承受总荷载达128 000kN;每座扣塔承受的竖向荷载为143 000kN,缆索吊机额定吊重360t,缆塔顶索鞍在横向±13m范围内可移动。该桥钢箱提篮拱节段顺利合龙证明,最终选定的方案特别适用于跨度大、自重大、空间位置复杂以及地形地质条件差等特点的提篮拱桥施工。The Xijiang River Bridge on the newly-built Nanning-Guangzhou Railway is a half- through steel box basket handle arch bridge with a main span 486 m. The maximum sectional di- mension of the steel box of an arch rib is 15.0 m×5.1 m and inner inclination angle of the arch rib is 4.8;. In the light of the structural characteristics of the bridge and the geological conditions of the bridge site and with reference to the construction experiences, two types of the erection schemes of the ＂vertical rotation of side segments＋lifting of middle segments＂ and the ＂cantile- ver assembling by the cable crane＋fastening stay method＂ for the arch rib were put forward. Through comprehensive comparison of the technical reliability, construction time schedule and cost, the latter erection scheme was selected. In the selected erection scheme, the anchorage are of the ＂clustering＂ prestressing rock anchors that are to be scatteredly arranged, the total load to be sustained by the anchorage is 128 000 kN, the vertical load each fastening stay tower is to sus- tain is 143 000 kN. The rated lifting capacity of the cable crane is 360 t and the saddle at the top of a fastening stay tower is movable in a range of ＋ 13 m in the transverse direction. The final smooth closure of the arch rib segments of the bridge proves that the erection scheme is particu- larly applicable to the construction of the basket h;ndle arch bridges that are characterized by the long spans, heavy self weight, complicated spatial locations and poor topographic and geologic conditions.

关 键 词：铁路桥 拱桥 钢箱拱 拱肋 缆索吊机 扣挂法 方案比选 桥梁施工 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]