VISCO-ELASTICITY IN TRAVELLING DEFLECTOMETERS

For some considerable time now the interpretation of deflection tests has moved away from an empiric approach in the direction of a more mechanistic approach. Generally elastic multi-layer theory is used to model the pavement structures investigated. Reiterative procedures ensure the best possible fit between measured and calculated deflection basins, assuming static loading but using "dynamic moduli". Static loading evidently is only the case in plate bearing tests but certainly not in Falling Weight Deflectometer (FWD) testing nor in travelling deflectometers like Deflectograph or Curviameter. As all road making materials, including the subgrade are to some extent of a visco-elastic nature the response to loading will be time dependant. Hence the peak deflection will shift away from the load centre. This shift will be influenced by speed and material characteristics. In this paper a general attempt is made to quantify this effect. More specifically it will be shown how visco-elastic Lacroix deflection curves may be transformed into their elastic counterparts, allowing subsequent elastic treatment. A comparison between corrected and uncorrected results is presented.

• Corporate Authors:

  Minnesota Department of Transportation

  395 John Ireland Boulevard
  St Paul, MN  United States  55155
• Authors:
  • Hoyinck, W T
  • Kuijper, R
• Conference:
  • 4th International Conference, Bearing Capacity of Roads and Airfields
  • Location: Minneapolis, MN
  • Date: 1994-8-17 to 1994-8-21
• Publication Date: 1994

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 445-456
• Serial:
  • Volume: 1

Subject/Index Terms

• TRT Terms: Alternatives analysis; Deflection tests; Deflectographs; Deflectometers; Dynamic modulus of elasticity; Elasticity (Mechanics); Falling weight deflectometers; Pavement layers; Plate bearing test; Static loads; Travel; Viscoelasticity
• Uncontrolled Terms: Pavement structure
• Old TRIS Terms: Curviameter; Dynamic moduli; Static loading
• Subject Areas: Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways;

Filing Info

• Accession Number: 00730068
• Record Type: Publication
• Files: TRIS, STATEDOT
• Created Date: Nov 27 1997 12:00AM