北京地铁七号线达官营站洞桩法开挖数值模拟研究

应用FLAC3 D软件，对静力作用下达官营站洞桩法开挖过程进行了数值模拟，研究了洞桩法施工各个阶段的地表沉降、桥基变形、管线变形、车站结构受力等。研究表明：洞桩法施工中，2＃桥基及各个管线的最大沉降量都超过了限值，应在施工过程中加强监测并采取控制措施。中柱作为结构的主要受力构件，承受较大竖向荷载、剪切荷载的双重作用，是结构的最不利位置，因此在施工中应重点监测，及时采取相应的加强措施，确保施工安全。

Simulation Investigation on Numerical Value of Hole-stake Excavation in Daguanying Station of Beijing Subway Line 7

The thesis simulates the excavation process of Daguanying Station under the statics function , studying the sedimentation of earth’s surface, the distortion of bridge groundwork, pipe and circuitry, and the structure stress of station of all the construction stages .The study shows that the most sedimentation of No .2 bridge groundwork and each pipe and circuitry exceeds the limit value , and it is necessary to strengthen inspec-tion and adopt control measure in construction .The middle stake must also be inspected and controlled carefully because it is the main stress structure which supports the vertical and shear loading and is at the worst position .