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”.
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.
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. and ... coming this winter, we are adding to our fleet with a new FastFWD!
