基于正交试验的隧道近接施工隔离桩优化设计  

Optimum design of isolation pile in tunnel close-spaced construction based on orthogonal test

作　　者：王祖贤 施成华[1] 陈刚 WANG Zuxian;SHI Chenghua;CHEN Gang(School of Civil Engineering,Central South University,Changsha 410075,China;China First Highway Engineering Company Ltd,Beijing 100024,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中交一公局集团有限公司,北京100024

出　　处：《铁道科学与工程学报》2020年第7期1785-1791,共7页Journal of Railway Science and Engineering

基　　金：国家重点研发计划资助项目(2017YFB1201204)。

摘　　要：隔离桩作为一种主要的施工控制措施广泛应用于隧道近接敏感建(构)筑物施工中,但目前尚未有规范对隔离桩的设计做出规定,现行隔离桩设计主要依据经验进行。针对这一现状,采用数值方法对影响隔离桩隔离效果的桩长、距隧道距离、桩径和桩弹模等4个主要因素进行正交试验,定义隔离系数并以此作为试验指标表征隔离桩隔离效果,分析评价各因素对隔离桩隔离效果的影响程度。研究结果表明:桩长是影响隔离桩隔离效果的最主要因素。进一步基于隔离桩影响因素评价对隔离桩合理桩长的确定进行设计优化,建议隔离桩桩长取1.2倍的隧底埋深时,能取得较好的隔离效果。As a main construction control measure,isolation piles are widely used in the construction of tunnel adjacent sensitive buildings.However,there is no specification for the design of isolation piles.The current design of isolation piles is mainly based on experience.In view of this situation,the orthogonal test was carried out for the four main factors affecting the isolation effect of isolation piles,which were the length of piles,the distance from tunnels,the diameter of piles and the elastic modulus of piles.The isolation coefficient was defined as an experimental index to characterize the isolation effect of isolation piles,and the influence degree of each factor on the isolation effect of isolation piles was analyzed and evaluated.The test results were analyzed by variance analysis and significance test.The results show that the length of the pile is the most important factor affecting the isolation effect of the isolation pile,while the other three factors have no significant impact on the isolation effect of the isolation pile.Based on the evaluation of the influencing factors of isolation piles,the reasonable length of isolation piles is optimized.It is suggested that the isolation effect is better when the length of isolation piles is 1.2 times of the depth of tunnel bottom.

关 键 词：隔离桩 正交设计 优化设计 合理桩长 

分 类 号：TU473[建筑科学—结构工程]