The Research of Low Temperature Performance of Asphalt Mixture

Abstract

To address Superpave graded and AC graded asphalt mixture, bending test at low temperature and thermal stress restrained sample tests are used respectively to evaluate the low temperature performance of asphalt mixture. Meanwhile, contrast analysis of the two test methods and the low temperature performance of two asphalt mixture are studied, too. The results show that Superpave method can effectively improve low temperature perfomance of asphalt mixture. In the thermal stress restrained sample tests, freezing temperature and transition point temperature can evaluate the low temperature cracking resistance of Superpave asphalt mixture well. In bending test at low temperature, bending strain energy density should be considered as evaluation index to the characterization for low temperature performance of asphalt mixture. That also closely meets the result of the rmal stress restrained sample tests.

Study on the Low Temperature Cracking Mechanism of Steel Slag Asphalt Mixture by Macroscale and Microscale Tests

“…Te type of load in the three-point bending test is very complex and is simplifed to the superposition of two load types, i.e., uniform load and trapezoidal load, as shown in Figure 11. When the crack length develops to x, the stress components corresponding to the crack surface position are shown in equation (11), respectively, uniformly distributed and trapezoidal loads, where W is the height of the beam specimen. In equation (11), the reference stress intensity factors corresponding to the two loads are as follows:…”

“…When the crack length develops to x, the stress components corresponding to the crack surface position are shown in equation (11), respectively, uniformly distributed and trapezoidal loads, where W is the height of the beam specimen. In equation (11), the reference stress intensity factors corresponding to the two loads are as follows:…”

“…Currently, standard evaluation methods for the low-temperature performance of asphalt mixture include the stifness modulus method, low-temperature shrinkage coefcient method, and low-temperature creep rate method, which are macroevaluation methods [8]. Cannone Falchetto et al [9][10][11] studied the low-temperature performance of the asphalt mixture. Te results showed that the macroscopic mechanical properties of materials were determined by their inherent mesostructure.…”