Lacroix deflectograph

The Lacroix Deflectograph is a pavement condition survey vehicle that is used for the following applications:

  • Measures the deflection basin of a pavement under the action of a moving heavy goods vehicle at constant speed.
  • It allows the application of the different operating modes of IFSTTAR method n°39 of surface deformability measures.

It is used for:

  • Monitoring a road network
  • Detectng defective areas to be reinforced
  • Checking construction sites
  • Winter monitoring (installation or removal of weight limits during thaw conditions).
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The Lacroix deflectograph consists of the following components:

  • A two-axle lorry with a minimum wheelbase of 6,800 mm, the rear axle being twinned and able to carry a load of 13 tonnes.
  • A reference beam equipped with two probe arms.
  • A system of traction and guidance of the beam with electronic control ensuring safety against the crushing of the ends of the beam.
  • An operator station allowing the piloting of the system by a computer and its dedicated software.

  • Condition survey speed: (3 +/- 0,5) km/h
  • Distance between two measurement steps: between 3 and 5 m according to the type of vehicle and the speed of condition survey.
  • Typically, a measurement step is composed of 81 sampling points spaced every 2 cm to restore the deflection basin.
  • Accuracy of the distance encoder: less than 5 mm

Download the Lacroix Deflectograph datasheet in PDF format


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