Methods and techniques used to investigate and test soil, rock and groundwater properties at a proposed construction site.
Geological Mapping: Mapping of the geological features of a site, including the location of different soil and rock types.
Site reconnaissance: Field investigation to gain an initial understanding of the site and identifying potential areas of concern.
Soil Sampling: Collecting soil samples for laboratory testing to determine the properties of the soil and its suitability for geotechnical construction.
Ground Penetrating Radar (GPR): A geophysical method for imaging and detecting subsurface geologic anomalies.
Cone Penetration Testing (CPT): A way to determine soil properties through the insertion of a cone-shaped instrument into the ground.
Standard Penetration Testing (SPT): A way to obtain information on the penetration resistance of soils by driving a split-barrel sampler into the ground using a standard weight and fall.
Borehole Logging: Collection and interpretation of data from a borehole, including rock/soil type, groundwater conditions, and strength.
Plate Load Testing: A field test to determine the bearing capacity of soil by loading a plate on the surface and measuring deflection.
In Situ Testing: Test procedures that evaluate soil behavior at the location where it is located, often used to determine soil variability.
Geophysical surveying: Using geophysical methods to identify and map the subsurface characteristics of the site, including groundwater depth and location of buried objects.
Groundwater Monitoring: The monitoring of groundwater levels, pressures, and quality to assess the water flow and its potential impact on geotechnical construction.
Slope Stability Analysis: The study of the stability of slopes, primarily those made up of rock, soil, or artificial fills.
Excavation and Shoring: Techniques used to control the excavation of soil or rock, including the installation of retaining walls or ground anchors.
Instrumentation: The installation of sensors and monitoring equipment to track changes in soil or rock movements, including vibrating wire piezometers, tiltmeters, and inclinometers.
Rockfall Mitigation: Methods to manage and reduce the risk of rockfall or mass movement hazards through the use of slope stabilization, rockfall netting, or rockfall barriers.
Soil exploration: Involves drilling boreholes and collection of soil samples for laboratory analysis to determine the properties of the soil.
Ground penetrating radar (GPR) survey: This type of investigation involves the use of radar waves sent into the ground in order to create an image of subsurface features and anomalies.
In-situ testing: A type of investigation that involves testing of soil properties directly in the field. Examples may include CPT (cone penetration testing), SPT (standard penetration testing), and PMT (pressuremeter testing).
Geophysical survey: This type of investigation involves the use of techniques such as seismic refraction, electrical resistivity, and magnetic susceptibility measurements to determine subsurface conditions.
Laboratory testing: This type of investigation involves testing of soil properties in a laboratory setting, examples may include Atterberg limits, grain size analysis, and direct shear tests.
Plate load testing: A type of in-situ testing which involves the application of a load to a small diameter plate placed on the surface of the ground. This allows for the determination of bearing capacity and settlement.
Shear vane testing: This type of in-situ testing involves the measurement of soil shear strength using a device known as a vane.
Thermal resistivity testing: This type of investigation involves the measurement of soil heat transfer properties in order to assess the potential for subsurface heating/cooling systems.
Instrumentation: This type of investigation involves the installation of measuring instruments on or below the surface for continuous monitoring of ground displacement, stability, deformation, and water pressures.
Environmental site assessment: Is the evaluation of the environmental condition of a site based on various investigations that include soil and groundwater sampling, geophysical surveys, and site history review.