Subsurface Investigations & Exploration

Early in the planning and design phase, Intertek-PSI’s geotechnical engineers provide subsurface investigations to evaluate a site’s soil and geologic conditions and identify potential risks that could impact site selection or foundation design for a variety of structures and buildings.

When Intertek-PSI’s team is engaged for subsurface investigations, a desk study, site visits and even potentially interviews are undertaken to help us build an initial site profile with typographical maps, and a comprehensive site history including regional geology. From there, we determine the methods of testing and sampling required, taking into consideration the site’s expected conditions, site access issues, proposed development type, project structural loads, and local regulations.

Intertek-PSI’s non-intrusive subsurface exploration methods include the use of a variety of in-situ tests like cone penetrometers, standard penetration tests, and shear vane tests. Our geophysical surveys provide additional geotechnical insights through the use of seismic refraction, ground penetrating radar, ultrasonic devices, and more.

Intertek-PSI’s intrusive subsurface investigations include various geotechnical drilling and sampling methods, exploratory borings, test pits, ground water observation wells, and the placement of geotechnical instrumentation devices like inclinometers or piezometers, settlement plates, concrete monuments

Subsurface investigations require a comprehensive geotechnical approach that includes multiple exploration and sampling techniques and laboratory testing methods to determine soil characterization, stratification, permeability, resistivity, compaction, and consolidation. Special in situ evaluations of the strength of soil are considered to provide value engineering to the projects; amongst these tests are: pressuremeter (PMT), dilatometer (DMT) and cone penetrometer test (CPT).

The result of this comprehensive approach to subsurface investigations is a report that includes boring logs, laboratory results, and a site map that details the field activities and testing methods used and summarizes the engineering analyses to provide design parameters that ensure a safe build and a resilient structure.