Stress distribution experienced under a portable light-weight deflectometer loading plate

Abstract

In the field of pavement engineering, the need to rapidly and economically obtain properties of soils and materials has given rise to the development of many non-destructive techniques. Portable light-weight deflectometers (PLWD) are relatively new deflection-based tools. As a consequence, the main factors influencing the quality of the results obtained using such a tool are still being investigated. Therefore, through finite element modelling and experimental measurements, this research focussed on the stress distribution and stress variability under a PLWD loading plate and how it is influenced by stress level, plate diameter, rubber mat use and rubber hardness. It was shown that the stress distribution factor used for the calculation of elastic modulus from deflection testing is significantly influenced by the loading plate diameter. Moreover, the use of a harder rubber mat was found to be better, but no significant effect was observed for bonded rubber mat conditions.

Keywords::

• light-weight deflectometer
• stress distribution
• finite element modelling
• pavement non-destructive testing

Acknowledgements

The authors wish to acknowledge the financial contribution of National Science and Engineering Research Council of Canada, the industrial partners of the NSERC Industrial Research Chair on the Interaction between Loads – Climate – Pavements and CarlBro. Special thanks are given to OpSens for their expertise in the engineering of the research equipment used in this study and to the research engineer Alexi Dejean for the completion of this project.

Notes

^1. Email: [email protected]