Mechanical Response of Pavements with Voids Under Traffic Load

This study aimed to explore the mechanical response of pavements with voids under traffic loads. A simulation test system for pavement structure damage caused by voids was developed. The dynamic evolution law of the stress, strain, and displacement fields in void evolution and development was analysed. In addition, the mechanical response of asphalt pavement with voids under the most unfavourable static and moving loads was studied using numerical simulation. The time history variation law of the three-dimensional strain response under different vehicle speeds and lateral loading positions was analysed. A comparison between the test and numerical calculation results shows that the voided pavement is prone to fatigue cracking, which gradually develops from the inside out. Under a moving load, the internal strain of the asphalt layer alternated between tension and compression before and after loading. The decrease in void depth and increase in void length aggravated the alternating amplitude changes of the tensile and compressive strains. Shear stress concentration appeared in the surface layer. The speed and lateral position of the vehicle load affect the strain response of pavement structures. With increasing vehicle speed, the peak values of the dynamic response of the three-dimensional strain of the asphalt pavement decreased. This research provides a reference for the damage mechanism of roads during their service life.