超深锚碇基坑围护结构施工关键技术

Key Technologies for Construction of Ultra-deep Anchorage Foundation Pit Enclosure Structure

摘要:

某大桥为双塔双跨悬索桥,主跨跨径达到1688米,边跨钢箱梁长548米,其西锚碇采用厚度为1.5 m的地下连续墙作为锚碇基坑开挖的主要围护结构,地连墙深入中、微风化泥岩,基坑开挖深度达到22.2 m,采用水泥粉喷桩加固软土。基于该大桥锚碇基坑围护结构施工,探讨超深锚碇基坑围护结构施工关键技术,并给出部分施工建议。

Abstract:

A bridge is a double-pylon double-span suspension bridge. Its main span is 1688 m long, and its steel box girder of side span is 548 m long. Its west anchorage adopts an underground diaphragm wall with a thickness of 1.5 m as the main enclosure structure for the excavation of the anchorage foundation pit. The underground diaphragm wall is embedded into the medium and slightly weathered mudstones. The excavation depth of the foundation pit reaches 22.2 m, and the soft soil is reinforced by the cement powder sprayed piles. Based on the construction of the anchorage foundation pit enclosure structure for the bridge, the key technologies for the construction of the ultra-deep anchorage foundation pit enclosure structure are discussed, and some construction suggestions are given.