Abstract: Dynamic compression tests on hydraulic asphalt concrete are carried out to study the dynamic mechanical properties under different temperatures. The test results show a strong dependence of the concrete failure mode on strain rate. At strain rates of 10-5/s and 10-4/s, the specimen mainly takes the mode of bond failure, while at strain rates of 10-3/s and 10-2/s, it takes bond failure and aggregate cracking. Temperature has a significant effect on the stress-strain characteristics of specimens. When the strain rate is ? 10-4/s, strain softening occurs at -5℃ and 0℃; strain hardening gradually develops from the threshold of 5℃.At a constant temperature of the concrete, its energy absorption capacity, elastic modulus, and compressive strength are all increased with the increase in strain rate. We analyze the dynamic increase factors (DIFs) of elastic modulus and compressive strength, and suggest an empirical formula for calculating the DIFs of elastic modulus for different strain rates at different temperatures. It is found that the S criterion of nonlinear uniaxial dynamic strength is a good parameter of hydraulic asphalt concrete reflecting the characteristics of growth in its dynamic compressive strength at different seismic response rates.

Key words: hydraulic asphalt concrete, dynamic mechanical property, failure mode, strain rate, energy absorption capacity