We present three case studies from recent site investigations that have utilised geophysical data to supplement traditional geotechnical investigations. The refraction microtremor (ReMi) method, which measures the shear-wave velocity of the subsurface soil profile, is used to enhance our overall understanding of geotechnical site conditions. Interpolation of the closely spaced one-dimensional velocity-depth profiles along linear arrays allows two- or three-dimensional velocity-versus-depth representations to be produced, thereby mapping lateral variations and extending subsurface characterisations between more expensive spot borehole measurements. The ReMi technique provides a non-invasive and cost-effective way of estimating vertical soil/rock shear-wave versus depth profiles and therefore is an effective reconnaissance tool for targeting key areas for further, more expensive intrusive investigation method. This paper examines the contribution ReMi shear-wave velocity assessments can make towards enhancing subsurface geological and geotechnical models to mitigate risk from unforeseen ground conditions. Case studies demonstrate the benefits of incorporating the shear-wave velocity estimates from ReMi into the geotechnical investigations. These include identifying the thickness of basalt flows, identifying the location of buried stream channels, characterising palaeo-topographical features, identifying areas of low velocity which may be prone to liquefaction, and assessing the thickness and velocity variations within geological units between borehole and test pit locations. The objective is not to replace traditional geotechnical investigations but allow more meaningful ground models to be developed.

我们介绍了最近现场调查的三个案例研究，这些研究利用地球物理数据来补充传统的岩土工程调查。折射微震 (ReMi) 方法测量地下土壤剖面的剪切波速度，用于增强我们对岩土工程现场条件的整体了解。沿线性阵列对紧密间隔的一维速度-深度剖面进行插值，可以生成二维或三维速度对深度的表示，从而绘制横向变化并扩展更昂贵的点钻孔测量之间的地下特征。ReMi 技术提供了一种估算垂直土壤/岩石剪切波与深度剖面的非侵入性和经济高效的方法，因此是一种有效的侦察工具，用于针对关键区域进行进一步、更昂贵的侵入性调查方法。本文研究了 ReMi 横波速度评估对增强地下地质和岩土工程模型以减轻来自不可预见的地面条件的风险的贡献。案例研究证明了将来自 ReMi 的剪切波速度估计纳入岩土工程调查的好处。这些包括确定玄武岩流的厚度，确定埋藏河道的位置，表征古地形特征，确定可能易于液化的低流速区域，评估钻孔和测试坑位置之间地质单元内的厚度和速度变化。目标不是取代传统的岩土工程调查，而是允许开发更有意义的地面模型。