【摘要】 洞桩法(PBA)在目前地下大型空间的修筑中已得到了广泛应用,但针对导洞开挖过程中,导洞开挖间距对地表沉降影响其研究相对较少。以北京某地铁车站实际施工工程为背景,基于依托工程,利用Madias GTX NX有限元分析软件建立有限元基本模型,并利用实际工程中导洞开挖的实际监测数据对基本模型在导洞开挖工序模拟中的可靠性进行了验证。随后在此基本模型上对相邻导洞间的不同开挖间距进行模拟分析,找出不同导洞开挖间距对地表沉降的影响和最佳的导洞开挖间距。研究结果表明,左右相邻导洞开挖间距7 m、上下导洞开挖间距14 m为最佳开挖间距,与实际工程相符。更多还原

【Abstract】 The Pile-Beam-Arch(PBA) method has been widely used in the construction of large underground spaces. However, there has been relatively little research on the effects of pilot tunnel excavation spacing on surface settlement during the excavation process. Taking the construction of a subway station in Beijing as a case study, this research establishes a finite element model using Midas GTS NX software based on the engineering project. The reliability of the basic model in simulating pilot tunnel excavation procedures is verified using monitoring data from the actual project. Subsequently, the model is used to simulate and analyze the effects of varying excavation spacing between adjacent pilot tunnels. The study identifies the influence of different pilot tunnel spacings on surface settlement and determines the optimal excavation spacing. The results indicate that the optimal excavation spacing is 7 m for horizontally adjacent pilot tunnels and 14 m for vertically adjacent pilot tunnels, which aligns with the actual project.更多还原