ABSTRACT
Based on static triaxial tests, uniaxial compression, and tensile tests of asphalt concrete, the stress-strain characteristics of asphalt concrete specimens under different temperature and confining pressure conditions are analyzed by using the test method of different test temperatures at the same mixing ratio to make up for the shortcomings of the current theoretical research on asphalt concrete strength. The temperatures include 5°C, 10°C, 15°C, and 20 °C, and the confining pressures include 0.1 MPa, 0.2 MPa, 0.3 MPa, 0.4 MPa, 0.8 MPa, and 1.2 MPa. The results show that under the same temperature condition, with higher confining pressure, the stress-axial strain curve becomes moderate, and the failure stress and its corresponding axis become larger when reaching the peak, which indicates that the creep of asphalt concrete becomes more obvious with higher confining pressure. Under the same confining pressure, the stress-axial strain curve becomes moderate with the increase in temperature, the smaller the failure stress at the peak, the larger is the axial variation value, which shows that the creep of asphalt concrete becomes more obvious with the increase in temperature. The failure form of asphalt concrete is gradually transformed from brittle damage to plastic damage, and the transformation rate is higher, which indicates that asphalt concrete is very sensitive to the change in temperature. Static triaxial test parameters were determined based on the Mohr-Coulomb strength theory. The boundary point between the Mohr-Coulomb strength theory and the Mohr-Coulomb strength theory first increased and then decreased with the increase in temperature, and the peak value appeared when the temperature was close to 15°C. The parameters of the static triaxial test were determined based on the Mohr-Coulomb strength theory. The boundary point between the Mohr-Coulomb strength theory and the Mohr strength theory first increased and then decreased with the increase in temperature, and the peak value appeared when the temperature was close to 15°C. In this paper, with the static triaxial test as the main test, uniaxial compression and tensile test as the auxiliary test, the strength theory of asphalt concrete was improved by comparing and analyzing the results of the three tests, which can provide the theoretical basis for the strength analysis of asphalt concrete.
