Correlation between light falling weight deflectometer results and laboratory measured elastic response of unbound materials

Coleri E., GÜLER M., Avsar C., Gungor A. G., Ozay O.

4th International Symposium on Deformation Characteristics of Geomaterials, Georgia, United States Of America, 22 - 24 September 2008, pp.831-837 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Georgia
  • Country: United States Of America
  • Page Numbers: pp.831-837
  • Middle East Technical University Affiliated: Yes


Measuring in-situ elastic response of unbound materials has gained considerable interest in the design and rehabilitation of road pavements. The use of Light Falling Weight Deflectometer (LFWD) offers significant advantage in terms of time and testing costs over the laboratory determination of resilient modulus. In this study, results of in-situ measurement of modulus using a standard LEWD device are presented for a number of project sections. Laboratory tests are conducted to determine the resilient modulus and various soil index properties for a number of soil samples. Statistical analyses are performed to correlate LFWD results with the measured modulus as a function of material type and the soil index properties. Analyses indicate that the in-situ modulus is generally higher than the modulus measured in the laboratory for the same project sections. Even though a direct relation between the in-situ and laboratory modulus is presented, it is, however, shown that more index properties are necessary to improve such correlations. The findings also indicate that statistical correlations can be significantly improved by using the maximum dry density and the plasticity index of soil samples.