响应曲面法优化城市深埋隧道新意法设计参数

Study on optimization of ADECO-RS approach design parameters of urban deeply buried tunnel by response surface methodology

以北京某深埋地铁隧道为工程背景,利用有限差分软件FLAC3D,采用三因素三水平的Box-Behnken设计方案和响应曲面法,对影响隧道拱顶沉降和掌子面挤出变形的主要新意法设计参数进行优化研究.结果表明,随着隧道埋深、跨径的增加,隧道拱顶沉降值以及掌子面的挤出变形值增大;超前预加固范围在1.1～1.5m增加时,拱顶沉降值及挤出变形值明显减小;超前预加固范围超过1.5m后其效果明显减弱.该隧道设计参数最优组合为埋深40 m、跨径12 m、超前预加固范围1.5m.运用响应曲面法优化深埋隧道新意法的设计参数是可行的,研究成果可为相关的隧道设计、施工提供参考.

This paper is concerned specifically with a novel study on the optimization of ADECO-RS approach main design parameters （depth, span and surrounding pre-reinforeement range in advance of the tunnel） exerting a large influence on the tunnel vault subsidence and excavation deformation of the tunnel face. This study is built on a typical engineering background--a deeply buried tunnel in Beijing and uses finite difference numerical analysis software FLAC3D, a three-factor, three-level Box-Behnken experimental design, and response surface methodology. The study suggests that the increasing depth and span triggers an increase in the values of tunnel vault subsidence and excavation deformation of the tunnel face; advance pre reinforcement ranging from 1.1 to 1.5 m contributes to a significant decrease in the values of tunnel vault subsidence and excavation deformation; the advanced pre reinforcement range over 1.5 m gives a significantly decreased effect. The tunnel design is unique with the optimal combination parameters such as depth of 40 m, span of 12 m, and the advanced pre reinforcement range of 1.5 m. The optimization of the design parameters of the deeply buried tunnel using response surface methodology proves feasible and provides the reference for the related tunnel design and construction.