A non-destructive testing device that evaluates the structural condition of pavements.

The Falling Weight Deflectometer (FWD) is a trailer-mounted system that applies a dynamic load, or “falling weight”, to a pavement surface and measures the resulting seismic response using geophones to capture changes in the pavement’s velocity or “deflection” - ideal for both road and airport testing.

FWD data is a cornerstone of pavement design and is extensively used worldwide to assess the performance, durability, and expected lifespan of pavements. It is a mandatory requirement for all NZTA and Auckland Transport reseal and rehabilitation projects.

The pavement response is analysed with Dynatest’s ELMOD (Evaluation of Layer Moduli and Overlay Design) software, which calculates the elastic moduli and stresses of each pavement layer. This analysis identifies the weakest layer, estimates residual life, and provides optimised rehabilitation recommendations, saving both time and resources for our clients.

Our FWD testing adheres to Austroads ASTM AG:AM/T006 standards and enables engineers to make informed decisions about pavement design, maintenance, and rehabilitation without damaging the road.

Benefits of the Falling Weight Deflectometer:

• Conducts rapid automated, structural pavement testing suitable for global applications
• Individual layer modulus determination
• Identifies specific pavement layers that are at risk of failure, offering more precise analysis than simple bearing capacity assessments
• Ideal for QA/QC of newly constructed pavements, ensuring compliance and performance
• Compares multiple rehabilitation options, such as plane-off and recycling, rather than simply applying overlays
• Provides accurate, reproducible, and repeatable structural data for informed decision-making
• Real-time and automated monitoring of load cell, geophones, and data variations ensures the highest quality data collection
• Mechanistic-empirical analysis applicable to a wide range of pavement structures.

The Falling Weight Deflectometer (FWD) is an essential tool for optimising pavement design, maintenance, and rehabilitation, offering reliable, actionable data to guide your infrastructure decisions. Our fleet includes the brand new Fast FWD and is based in Tauranga with nationwide coverage for all road and airport testing.