深圳地铁软硬不均复杂地层盾构施工对策

Countermeasures for Shield Tunneling in Hard and Soft Mixed Strata of Shenzhen Subway

深圳地区地处沿海丘陵台地,地形、地层复杂,有杂填土层、填海块石层、淤泥层、冲洪积层和冲洪残积层等。地铁线路的迅猛增加,使得盾构隧道穿越更多的软硬不均、硬岩、孤石、断裂破碎带和水底浅覆土等复杂地层,施工进度和安全经常受到影响。在这些复杂地层中推进,将大大增加盾构机土舱压力、掘进参数、同步注浆、姿态调整和地表沉降的控制难度,并导致刀具磨损加快等一系列技术问题。文章介绍了深圳地铁5号线在各类复杂地层中盾构施工的经验和做法,对其工程特点和影响进行了分析。本工程通过采用一些辅助工法优化掘进参数,使得盾构机安全顺利地通过了该类区域。

Shenzhen district is situated on the coastal hills and mesas with complex topography and strata, consiting of miscellaneous fill layer, reclaimed stone layer, silt layer, alluvial layer and residual alluvial layer and so on. With the rapid development of subway lines, shield tunnels have to drive through hard rocks, boulders, shallow fracture zone, under water layer and other complex geological areas. The difficulties of driving through these complex layers will be greatly increased including the control of soil cabin pressure, driving parameters, grouting, posture correction, soil displacements and surface subsidence, incorporating a series of technical problems such as accelerated wear of cutting tools. This paper introduces the experience and practice of shield tunneling of Shenzhen metro Line 5 under the condition of various complex strata and analyzes the impact and characteristics of the project. By using a number of construction methods and optimized driving parameters, safe and smooth shield driving through the region has been realized.