Geotechnical Services from Terrane
When are Geotechnical Services Needed?
Geotechnical consulting services may be required during any phase (feasibility through construction) of a project or development. The nature of services required will vary according to the phase the project is in, the scale of the project, and the type of project.
Feasibility & Planning
Feasibility and planning studies are usually reserved for large-scale projects such as dams, landfills, utility and transportation corridors, large recreational, residential and commercial developments, and factories. The primary activities during these phases are generally literature review and expert reconnaissance. In some cases, interviews and limited exploration and testing are performed. From these activities, preliminary engineering, geological. and groundwater reports are developed which can be used for "fatal flaw" analysis, comparative evaluation of candidate sites or alignments, or site use planning.
Geotechnical services are needed during the design and construction phases of all projects regardless of size (from a convenience store to a skyscraper). The primary activities for the design phase are site exploration, soil testing, and engineering analysis. From these activities a geotechnical report is prepared for use by the designer. The content of geotechnical reports varies according to the project type (building, bridge, dam, highway, landfill, subdivision, etc.). but most reports provide information and recommendations regarding:
Other subjects which may be addressed depending on project conditions and requirements include slope stability, soil stabilization, seepage, percolation, and ground compaction and shrinkage.
- Existing soil, geology, and groundwater conditions
- Foundation types, capacities, and depths
- Earthwork factors such as site preparation, excavation conditions, suitability of site materials, and compaction criteria
- Pavement types and thicknesses
- Construction materials and inspection
The primary activities during the construction phase are observation and testing by the geotechnical engineer or his representative. In some cases, additional exploration and recommendations are required for unusual or unanticipated conditions. The purpose of the observation and testing activities is to provide reasonable assurance that actual conditions are consistent with those encountered during exploration, that earthwork is performed in general accordance with specifications, and that materials such as aggregate, asphalt concrete, geosynthetics, and Portland cement concrete meet specifications.