Engineering Geological Survey
Engineering geology is a multidisciplinary science that combines engineering, soil mechanics, and geology to guide the design and construction of engineering projects in soil and rocks. Engineering geologists provide technical advice on the kind of engineering works that are best suited to the type of earth material at a particular site, and they also provide advice on how potential engineering and geological issues need to be managed. The goal of engineering geological surveys is to determine the characteristics of geological bodies, geological structures, and geomorphology at the subsurface that could influence design and construction decisions. It is also used to assess the impacts of proposed projects on geological and geomorphological environments.
The work of engineering geologists involves mapping and lithologic description of the subsurface, as well as collection and interpretation of geologic data such as core, sonic logs, dip measurements, seismic reflection and refraction, slope stability analysis, and various types of groundwater testing. All of this information is then used to assess the engineering characteristics of the site, evaluate the risk of artificial or natural disasters, and plan for the construction of the project.
Engineering geological surveys may be carried out to obtain information on different aspects of a project. These include:
• Estimating groundwater resources
• Estimating the capacity of soils, rocks and other materials to support foundations
• Identifying potential earthquake risk and assessing construction tolerance
• Evaluating stability of dams, embankments, slopes and other earthworks
• Location and delineation of potentially contaminated land
• Identification of voids and potential instability
The type and extent of the survey will depend on the project, the geological conditions, and the potential risks associated to it. Engineering geological surveys can take a variety of forms depending on the aims of the survey. A detailed investigation may involve a range of techniques including geophysical surveying, sampling and laboratory testing. This will allow for a more complete evaluation of the geological conditions and engineering properties of the subsurface materials. If greater detail is required, sampling for laboratory tests can be performed as part of the engineering geological survey.
Most engineering geological surveys involve mapping the surface geology and subsurface geology to map its engineering and geological characteristics. The depth of the subsurface mapping will depend on the scale of the project and the depth at which the engineering properties of the subsurface material could become important. It is also important to map subsurface structures such as faults, and to examine them for engineering implications.
Engineering geological surveys are an important part of planning and executing any construction project and provide invaluable insight into the subsurface geology and engineering properties. This information is critical for making informed decisions about how best to manage the risks and challenges associated with a project, and how to protect the environment. They also help to ensure that projects are completed safely, efficiently and cost-effectively.
