Falling Weight Deflectometer

FWD is a trailer mounted dynamic impulse loading device which can be towed by any suitable towing vehicle and is used for non destructive testing of pavements.

The outputs from FWD are:

• Deflection bowl (Transient Deflections at seven different points, spaced 300 mm apart)
• Back Calculated Layer Moduli
• Overlay design
• Remaining/Residual life of the pavement
• k-value
• Load transfer efficacy
• Pavement Classification Number (PCN) value
• Stresses/strains

The unique features of FWD are:

• Follows largely the mechanistic approach
• Enables design/evaluation based on fundamental material properties
• Loads pavements dynamically and simulates actual traffic loading and loading duration
• Back calculated layer moduli computed from deflection measurements are nearly representative of the field conditions