ABSTRACT
As required for any geotechnical projects, site investigations need be conducted to obtain the information required for the design of drilled shafts in rock. The nature and extent of the information to be obtained from a site investigation will vary according to the project involved and the expected ground conditions. A site investigation is a process of progressive discovery, and, although there must be a plan and program of work at the beginning, the information emerging at any stage will influence the requirements of subsequent stages. Typically, a site investigation consists of the following three main stages:
1. Preliminary investigation including desk study and site reconnaissance 2. Detailed investigation including boring, drilling, in situ testing and lab testing 3. Review during construction and monitoring
A distinguishing feature of site investigations for foundations in rock is that it is particularly important to focus on the details of the structural geology. The rock mass at a site may contain very strong intact rock, but the discontinuities in the rock mass may lead to excessive deformation or even failure of the drilled shaft foundations in the rock mass.
