软硬不均地层盾构姿态控制及管片防裂损技术

Shield Driven Tunneling in the Complex Layer:Direction Control of Shield and Preventing Segment Crack

广州地铁二号线越—三盾构区间的地层软硬不均,加之曲线多、坡度变化大,盾构掘进技术难度大,掘进方向与盾构姿态的控制困难,防止管片开裂和局部破损以及错台具有一定的难度。为了有效地控制掘进方向和盾构姿态,研究了盾构掘进方向发生偏差的原因,并对越—三区间盾构掘进的偏差实测数据进行具体分析,得出了偏差的原因和规律;研究了盾构掘进姿态的控制方法。为了防止盾构管片的裂损,采用数值模拟方法研究管片裂损的规律及其主要因素,提出了有效控制管片裂损的主要方法。

The ground layer of the No. 2 Metro Line in Guangzhou has the characteristics of mixed ground conditions： more curves and big gradient variation. So it is difficult to excavate successfully and control the tunneling direction and shield tunneling attitude. Furthermore, it is also difficult to prevent segment crack and local failure and dislocation of segment. In order to control the tunneling direction and shield tunneling attitude more successfully, the reason of direction warp was studied and the actual measure data of Yue-San shield tunneling zone were analyzed. At last, the reason and the rule of direction warp were got and many methods to control shield tunneling attitude were tried. The main cause of segment crack and local failure of segment, were also studied with numerical simulation, and methods to control segment crack were brought forward.