Determination of the elastic modulus of road pavements using dynamic testing methods
The article presents various experimental methods for determining the elastic modulus of road pavements, including the dynamic loading of DINA-3M, results of determining the elastic modulus by dynamic test methods and coefficient of variation. The article analyses various methods for determining the elastic modulus of road pavements in terms of their advantages and disadvantages: laboratory tests, the impact penetration sensing method and a method based on the deviation of the coating surface. Additionally, the structure and operational principles of DINA-3M unit are discussed. In 2018, as a result of its use, the elastic modulus of the road pavements of the M-53 “Baikal” highway was determined from 1843 km +500 to 1852 km +500. The elasticity modulus of the pavement varies from 602 to 1343 MPa, corresponding to a change in the coefficient of variation of the modulus of elasticity of the pavement in the range of 12 - 50 %. A comparison was made between all values obtained for the actual modulus of the road structure at the working stage with the values of the minimum required elasticity modulus (E<sub>TR</sub>). The results allow us to estimate the real quality of the construction layers and underlying ground structure, as well as to form a conclusion about the uniformity of the road pavement’s strength index. The determination of the modulus of elasticity and strength of the road pavement is a significant work in the inspection and evaluation of the existing road construction. In the surveyed section of the M-53 “Baikal” highway, the coefficient of variation of the elastic modulus of the road pavement can vary in the range of 12 - 50 %. This indicates a considerable heterogeneity in terms of the pavement’s modulus, which must be considered when planning repair activities.