盾构法适宜在较均一的软土、软岩地层或砂层及其互层的地层中掘进，但在软硬不均、软硬交互且岩石强度差异大的地层中应用盾构法修建城市地铁隧道就复杂得多。以广州地铁三号线盾构区间工程为实例，介绍盾构法隧道长距离硬岩地层段采用钻爆法开挖管片衬砌施工技术。

Shield tunneling technology is suitable for homogeneous ground consisting of soft soil, soft rock, sand or their alternative layers. However, it will be much more complex when shield tunneling technology is used in softhard heterogeneous ground, softhard alternative ground or ground with great difference in strength. Taking the shielddriven tunnel works of line 3 of Guangzhou Metro as example, the article presents the shield construction technology taken for the longdistance hard rock ground, where the tunnel is excavated by means of drill+blast method and is lined by segments.