上软下硬岩溶区隧道下穿机场滑行道桩托板支护效果分析

Analysis on Support Effect of Pile Supporting Plate for Tunnel Undercrossing Airport Taxiway in Upper-soft and Lower-hard Stratum

由于机场区域的特殊性及其严格的安全控制要求,隧道下穿越机场滑行道工程施工技术难度大。依托某上软下硬地层隧道下穿机场滑行道工程,采用FLAC 3D有限元软件分析“桩托板”防护体系的加固效果,研究机场滑行道的沉降规律与隧道施工力学行为。研究表明:采用“桩托板”防护体系对机场滑行道道面的横向及纵向沉降均有明显的控制作用。“桩托板”结构中“桩”的结构受力要大于“板”,主要承受竖向应力,其最大值小于结构设计强度,“桩托板”防护体系结构是安全的。

Due to the particularity of the airport area and its strict safety control requirements,the engineering construction technique of the tunnel under-crossing the airport taxiway is difficult.Based on the construction project of an upper-soft and lower-hard stratum tunnel under-crossing the airport taxiway,the 3D finite element software FLAC is used to analyze the reinforcement effect of the“pile supporting plate”protection system,and to study the settlement law of the airport taxiway and the tunnel construction mechanical behavior.The research shows that the use of a“pile supporting plate”protection system has an obvious control effect on transverse and longitudinal settlement of the airport taxiway surface.The structural stress of the“pile”in the“pile supporting plate”structure is greater than that of the“plate”,and it mainly bears vertical stress,with its maximum value less than the structural design strength.The“pile supporting plate”protection system structure is safe.