武汉阳逻长江公路大桥南锚碇圆形深基坑变形影响因素的灰色关联分析

武汉阳逻长江公路大桥南锚碇圆形深基坑工程采用地下连续墙工法施工。为确保附近长江大堤的安全,要求严格控制基坑变形。在对该工程施工情况简要介绍后,通过分析,从影响基坑变形的众多因素中,选择出主要可调施工参数,即基坑分层厚度、基坑内衬厚度及岛式开挖的周边挖土宽度,并运用灰色关联理论对这些参数与墙体变形进行了关联分析。分析结果表明,在这3个施工参数中,分层厚度对地连墙变形的影响最为显著,其次为周边挖土宽度,内衬厚度对地连墙变形的影响相对最小。因此,为减小基坑挡墙的变形,相对于增加基坑的内衬厚度,调整基坑的分层厚度及周边挖土深度是更为经济有效的方法。该分析方法与结论为调整阳逻大桥南锚碇基坑及其他类似圆形基坑的施工方案进而控制基坑变形、实现基坑工程的信息化施工提供了一种新的思路和理论依据。

GREY-CORRELATION ANALYSIS OF FACTORS INFLUENCING DEFLECTION OF THE ROUND FOUNDATION PIT OF THE SOUTH ANCHORAGE OF WUHAN YANGLUO YANGTZE RIVER HIGHWAY BRIDGE

To ensure the security of the Yangtze River levee nearby,the deflection of the diaphragm wall of the round foundation pit for the south anchorage of Wuhan Yangluo Yangtze River Highway Bridge must be strictly controlled.So after the brief presentation of the construction process of the project,factors that contribute to deflection of the diaphragm wall are examined;and three parameters,namely depth of excavation layers,thickness of inner lining and width of excavation part,are recognized as the main factors.Then grey-correlation theory is applied to analyze the correlation between these parameters and deflection of the diaphragm wall.It is shown that depth of excavation layers and width of excavation part have more influence than thickness of inner lining.Therefore,to restrict the deflection of the diaphragm wall,it is more efficient and economical to adjust the depth of excavation layers and/or the width of excavation part than to increase the thickness of inner lining.The analysis method and the conclusion can be applied to this project and other similar projects.