川滇金沙江特大桥施工关键技术

Key Construction Technologies of Sichuan-Yunnan Jinsha River Special Bridge

摘要:

为研究悬索桥施工过程中的关键工序与技术对整个工程的造价、工期及风险控制的影响，结合川滇金沙江特大桥的施工特点，通过优化施工工艺，安全高效的完成了该桥的建设，并缩短了工期，降低了工程造价。该桥主塔施工采用下横梁塔梁异步、上横梁塔梁同步与主动横撑配套施工工艺，确保了主塔与横梁受力及线形要求；重力锚施工采用了非闭合式拱形咬合桩基坑支护体系，减少了支护结构的工程数量，保证了基坑边坡的稳定性；主缆采用预制平行钢丝索股架设，利用双线往复式牵引系统进行索股牵引，确保了工程质量与效率；钢桁梁采用厂内杆件制造、现场总拼与缆索吊装智能监控系统吊装工艺，精确高效的实现了全桥合龙。

Abstract:

In order to study the impact of key processes and technologies in the construction process of suspension bridges on the cost, duration and risk control of the entire project, combined with the construction characteristics of the Sichuan - Yunnan Jinsha River Special Bridge, the construction of the bridge has been completed safely and efficiently by optimizing the construction process. The construction period is shortened, and the engineering cost is reduced. The construction technology of asynchronous lower crossbeam and pylon beam, and synchronous upper crossbeam and pylon beam supported with the active cross braces is adopted in the construction of the main bridge pylon, which ensures the stress and linearity requirements of the main pylon and crossbeam. A non-closed arched interlocking pile foundation pit support system is used in the construction of the gravity anchor, which reduces the engineering number of support structures and ensures the stability of the foundation pit slope. The main cable is erected by using prefabricated parallel steel wire strands, and the double-line reciprocating traction system is used for strand traction to ensure the quality and efficiency of the project. The hoisting process of in-factory member manufacture, on-site assembly and cable hoisting intelligent monitoring system is adopted for the steel truss girder, which has precisely and efficiently achieved the closure of the whole bridge.