The Heavy or Falling Weight Deflectometer (F/HWD) is a non-destructive pavement assessment device. The F/HWD test is based on the measurement of the deflection generated by an impulse loading. F/HWD tests are generally analysed by inverse analysis methods, the purpose of which is to determine the mechanical properties of the pavement layers. Despite its widespread use on road and airport pavements, it turns out that the data from this test are often interpreted within a questionable background because the elastostatic method commonly used does not consider dynamic effects and limits the behaviour of bituminous materials to linear elasticity. In this doctoral dissertation, a dynamic viscoelastic inverse analysis method is proposed. After having been verified and evaluated, it is applied to HWD tests carried out on the STAC test facility at several pavement temperatures between 0°C and 30°C. The results are compared with those obtained by the classical elastostatic and elastodynamic methods. The linear viscoelastic properties deduced from the HWD tests are also compared to the results of complex modulus tests on the materials of the test facility carried out in the ENTPE laboratory.
Contribution of linear viscoelasticity in the dynamic analysis of Heavy Weight Deflectometer test