The GeoGauge is a unique, QC/QA field tool that can be used to measure the uniformity of unbound pavement layers by measuring the variability in stiffness throughout a structure.


It is an excellent tool for identifying construction anomalies that would otherwise go undetected duringconstruction where only density or percent compaction measurements were used. By measuring stiffness, theGeoGauge can reveal and thus help reduce variabilities in layer properties, which density measurements may miss, thus allowing corrective actions to be taken duringconstruction to ensure that the highest quality base and subgrade are achieved despite variations in materials used.

The GeoGauge works by applying a vibrating force at 25 specific frequencies, which produce small deflections in the material. The resulting displacement is measured by the GeoGauge and displayed as stiffness determined by the ratio of the force to deflection. The GeoGauge produces stress and strain levels common for pavement, bedding and foundation applications.


  • Dynamically measures in-place engineering properties using structural layer stiffness, MN/m (klbf/in) and Young’s Modulus of a material, MPa (kpsi)
  • In-place QC/QA links compaction and material performance directly to design requirements while advancing Mechanistic-Empirical Pavement Design
  • Enables maximum lift stiffness with minimum compactive effort
  • Facilitates uniform stress transmission and distribution from pavement to subgrade resulting in longer pavement life, reduced maintenance costs and longer lasting surface smoothness.
  • Enables reduced structural variability in construction
  • In-place QC/QA of the strength gain of stabilized materials
  • Data base development supporting Mechanistic-Empirical Design and performance specifications
  • Portable, fast, simple, reliable, non-invasive
  • Other compaction applications include: lime, cement, fly-ash and polymer stabilized materials, cement-treated and rehabilitated bases, large particle aggregate bases, as well as underground utility backfills.


  • Layer Stiffness – 17 to 400 klbf/in (3 to 70 MN/m)
  • Young’s Modulus (in-place) – 4 to 90 kpsi (26 to 610 MPa)
  • Measuring Depth – 9 to 12 inches (230 to 310 mm)
  • Measuring Duration – 75 seconds
  • Power – six D-cell batteries (1000 to 1500 measurements)
  • Dimensions – gauge only: 11” dia. X 10.5” high (280mm x 270mm) carrying case: 18.5” x 16.5” x 13” (470 x 420 x 330mm)
  • Net Weight – gauge only: 22Ibs. (10kg) With case: 34Ibs (15.5kg)
  • Shipping Weight – 39Ibs (17.7kg)