Falling Weight Deflectometer (FWD) is a device used to evaluate the bearing capacity and structural condition of road and ground pavements. This device is used to determine the engineering properties of asphalt, concrete or other ground pavements in particular and has important application areas such as:
Purposes of Use:
Evaluation of Road and Ground Pavements:
Determines the elastic modulus and load-carrying capacity of pavements.
Analyzes surface deformations and the condition of ground layers.
Determination of Bearing Capacity:
Determines maintenance and repair requirements by testing the bearing capacity of pavement and subgrade layers.
Evaluates whether the roads are suitable for future usage intensity.
Structural Design and Maintenance Planning:
Used in the optimization of road maintenance plans.
Helps evaluate ground properties in new road designs.
Analysis of Soil and Subgrade Layers:
Evaluates inter-layer performance by measuring the reactions and deformations of different layers in the road.
Working Principle:
Falling Weight Method: The device applies a load by dropping a controlled weight on the surface and measures the deformations resulting from this load.
Deformations are usually measured at the millimeter level by sensors located on the pavement surface.
The obtained data is used to calculate the elastic properties of the ground and pavement layers.
Areas of Use:
Highways: Control of the carrying capacity of highways and pre-maintenance evaluation.
Airports: Analysis of the carrying capacity of runways.
Railways: Measurement of the durability of sub-rail ground structures.
Industrial Facilities and Ports: Analysis of ground durability in areas with heavy vehicle traffic.
Compliance:
1. ISO 9001
2. ISO 14001
3. OHSAS 18001
4. AASHTO R32
5. ASTM D4694
6. ASTM D4695
7. FAA AC 150/5370-11B
8. ICAO Annex 14 Volume 1 - Aerodrome - Design and Operation
9. CASR Part 139 - Aerodrome (Civil Aviation Safety Regulation)
Software
Every day your pavements are subjected to the traffic loads that are driven on them. When roads are built, the design is calculated based on the load that the pavements must be able to carry at current levels.
The analysis and calculation of data collected with the PRIMAX HWD and SHWD with PRIMAX Design Software allows you to evaluate the pavement layer condition development in order to optimize your pavement maintenance planning:
Like all Sweco FWD equipment, both trailer-mounted and truck-integrated, it is supplied with a personal computer, Windows FWD software, time history module, transport lock, DMI (Distance Meter Indicator) integrated in the software, three temperature sensors, four-section loading plate, 9 -14 or up to 16 geophones and warning lights.
Safety
The equipment cannot be driven to another position with the loading plate down, and strategically placed emergency switches allow the operator to stop the equipment at any time while working from the vehicle.
The PRIMAX software includes alarms that are displayed on the computer screen.
Certain functions cannot be performed with the FWD if the operator ignores vital warnings, e.g. in connection with pavement temperature measurement: After inserting the asphalt temperature sensor into a hole in the pavement, the sensor registers that the temperature is stable.
The temperature is measured when the loading plate is placed on the pavement and cannot be increased before the temperature sensor is placed in its holder.
PCN and PCR - values
Dynamic E modules
Remaining service life
Determination of critical layer
Reinforcement (coating) requirements
Integrated online support for remote system monitoring and support
Fully connected and compatible with RoSy RAMS or APMS, allowing easy import/export of data
PRIMAX Design software can also calculate data collected by FWD from other manufacturers.
PRIMAX1500 FWD
Automatic IR pavement surface temperature transmitter
Extended deviation sensor capacity (up to 16)
Automatic spray marking equipment
Road guidance system (Airport measurements)
Road imaging system
Positioning camera
Safety signage
All that is required to upgrade the equipment from the standard 7-150 kN FWD to a 7-250 kN Heavy Weight Deflectometer (HWD) or even a 7-350 kN Super Heavy Weight Deflectometer (SHWD) is more weight, a larger load cell and a software upgrade.
The trailer-mounted FWD can also be integrated into a pickup truck without having to invest in new basic measurement equipment.
Optimum safety and performance
Automatic equipment safety monitoring and alerting system
Cost and time-reducing product solutions for surveys
Scalable load options - upgradeable on demand
Project navigator for project management
Collaborative software solutions
Integrated online support for remote system monitoring and support
Fully connected and compatible with RoSy RAMS and APMS for easy data import/export
Real-time data calculation of E modules during field measurements