孤石在我国南方花岗岩地区普遍存在，其分布无明显规律，形状各异，强度可达到100 MPa以上。福州地铁1号线在施工过程中遇到了孤石问题，盾构区间范围内的孤石如果没有提前查明并处理，会给盾构施工造成重大不利影响和安全隐患。采用微动探测方法有效解决了福州地铁1号线的孤石问题，运用微动探测成果结合少量钻孔验证进行盾构施工的安全性分析，为盾构施工提供指导。简要阐述了微动探测方法的基本原理，介绍其在福州地铁1号线多个盾构区间孤石探测的成功案例，说明微动探测方法适用于城市复杂的环境条件，在盾构施工孤石探测方面具有良好的应用效果。

The boulders (spherical weathered granite) exist commonly in south China; and the compression strength of boulder can reach 100 MPa. The boulders occurred during shield tunneling of Fuzhou Metro Line No. 1, which would lead to potential safety risk. The microtremor method is adopted to detect the boulders of Fuzhou Metro Line No. 1. The application results are testified by borehole drilling. The working principle of microtremor detection method is introduced. The application results of the microtremor detection method to Fuzhou Metro Line No. 1 show that the abovementioned method is reliable and effective in complex urban area.