膨胀岩土具有遇水膨胀和失水收缩的特点。在膨胀系数较大的岩土层中,盾构很容易被遇水膨胀后的岩土裹住,导致盾构方向无法控制,最终可能造成隧道线路偏差超限。本文通过工程实例介绍盾构被膨胀岩土裹住无法控制方向时的脱困措施和经验,以资同仁参考。 Expansive rock with water swelling and water shrinkage characteristics. In geotechnical layers where the coefficient of expansion is large, the shield is easily entrapped in the rock after the water swells, resulting in uncontrollable shield orientations that can eventually result in overrun of tunnel lines. In this paper, engineering examples are introduced to shield the expansive soil wrapped uncontrollable direction of the detached measures and experience to colleagues reference.