Road Performance of Polyurethane Mixtures and Load Response Behaviors of Typical Polyurethane Pavement Structures

In order to clarify the road performance and load response behavior of polyurethane mixtures, a low-temperature bending test, dynamic modulus test, rutting test, Hamburg rutting test, and four-point bending fatigue test were conducted on multi-crushed stone polyurethane concrete (SPC-16) and polyurethane concrete (PC-20) as the test objects, and the results were compared with the road performance of an asphalt mastic crushed stone mixture (SMA-13). The differences in the load response between two typical polyurethane mixture pavement structures and a typical asphalt pavement structure were analyzed under four working conditions: a normal-temperature standard load, normal-temperature heavy load, high-temperature standard load, and high-temperature heavy load. The results showed that the low-temperature flexural tensile strength of the polyurethane mixture was 1.3–1.7-times that of SMA-13, the maximum flexural tensile strain was 1.1–1.8-times that of SMA-13, the dynamic stability of the polyurethane mixture was more than 15-times that of SMA-13, and the fatigue life of the polyurethane mixture was 8–12-times that of SMA-13. The surface deflection, base stress, and surface strain of the typical asphalt pavement structures and two typical polyurethane mixture pavement structures at the same temperature all increased with an increase in the load. The load response of the polyurethane mixture pavement structures under high-temperature conditions was relatively stable.