Upgrade your Pavement Analysis today!

You can with Dynatest’s geophone conversion pack improve your measuring results on thin asphalt layer pavement and other types of surface layer even block pavements.

Dynatest Senior Pavement Engineer, Umberto Pinori, and Albert Navarro, project Manager, has in collaboration with Professor, Eyal Levenberg, from the Technical University of Denmark (DTU) developed a new solution to increase the quality of the bearing capacity evaluation using Falling Weight Deflectometer and Fast Falling Weight Deflectometer.

The study was driven by the need for improved moduli back-calculation of the upper layers in asphalt pavements.

Senior Pavement Engineer Umberto Pinori

Umberto P

The study was presented at TRB in Washington, 8th of January 2024.

By adding an extra geophone!

The improvement was achieved by modifying the Falling Weight Deflectometers design to host an extra geophone at a nontraditional offset of 100mm, i.e., within the loading plate.

Adding an extra geophone at 100 mm from the center of the load the deflection basin is collected with more accuracy to improve the back-calculation results.

This new feature will provide significant value for both existing and new Dynatest Falling Weight Deflectometer equipment (applies for FWD and Fast FWD), particularly for users testing thin top asphalt layers or similar materials.

Elevate Your Pavement Testing

If you add an extra geophone at 100mm from the center of the load, inside the load plate, the additional 100mm geophone improves the accuracy of the deflection bowl trend.

In case of thin layer asphalt, assuming a theorystress distribution of 45° the deflection recorded by the second geophone, placed at 200mm, is not influenced by the first layer.

By introducing the 100mm geophone it is possible to have two geophones recording the influence of the first layer in the pavement deflection, adding key elements to increase the quality of the back-calculation process.

Plug & play - Upgrade your FWD and Fast FWD


You can with Dynatest’s geophone conversion pack improve your measuring results on thin asphalt layer pavement and other types of surface layer even block pavements.

Seamless integration process, making it easy to measure thinner asphalt pavement layers and other surfaces using our Falling Weight Deflectometer and Fast Falling Weight Deflectometer.


Complete Conversion pack includes:  

  • 1 pcs. Upper loading plate
  • 2 pcs. Quarter plate segment
  • 1 pcs. Geophone 80 or 100mil
  • 1 pcs. Geophone holder
  • 1 pcs. Upper flange for loadcell
  • 1 pcs. Mount Ring for raise-lower Guide

If you are interested in the conversion package and want to start measuring thin asphalt layers today!

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