Which geophysical methods do I need for geotechnical applications?

Arguably, the most common geophysical methods for geotechnical applications are GPR, resistivity and seismics. In most situations, especially for complex problems, a combination of results from several different methods is favourable.

The most common geotechnical application is to define the topography and depth to bedrock, as well as mapping of low bearing capacity areas such as clay, peat, or other soft soils. Further on, the need of mapping fractures and weakness zones in bedrock is vital for both tunnelling and construction work above the bedrock, and the stiffness of the ground is an important parameter when building close to roads, railways.

Use GPR to

  • Map depth and topography of bedrock
  • Map non-conductive soil layers and peat
  • Map utilities and other underground construction to avoid damages on the same, during drilling / digging.
  • UXO detection
  • Perform a fast and inexpensive reconnaissance of an area of interest

Use resistivity to

  • Map depth and topography of bedrock.
  • Map fractures and weakness zone in bedrock.
  • Map soil layers and peat.
  • Map ground contamination prior construction work.
  • Map groundwater conditions prior construction work.

Use seismics to

  • Map depth and topography of bedrock.
  • Map fractures and weakness zone in bedrock.
  • Map earthquake resilience when constructing in seismically active areas.
  • Map the shear wave velocity to get the shear strength of the ground.

 

Note! Most often you could use two or three different geophysical methods, as well as you choose several drilling techniques, to get the most comprehensive results of your subsurface conditions. Of course, this will be a balancing between the amount of information and total cost.

 

More to read

Application areas
https://www.guidelinegeo.com/application-areas/

Methods
https://www.guidelinegeo.com/ground-penetrating-radar-gpr/
https://www.guidelinegeo.com/resistivity-and-induced-polarization/
https://www.guidelinegeo.com/transient-electromagnetics-tem/
https://www.guidelinegeo.com/seismic-methods/

Case Stories
https://www.guidelinegeo.com/solutions/case-stories/

Products
https://www.guidelinegeo.com/mala-ground-penetrating-radar-gpr/
https://www.guidelinegeo.com/abem-resistivity-seismics-tem/