高黏弹性沥青砂的抗裂性能研究

Analysis on Anti-cracking Performance of High Viscoelastic Tar Sand

应用断裂能理论来研究高黏弹性沥青砂的抗裂性能。通过在不同的试验温度与加载速率条件下进行SCB试验(Semi-Circular Bending Test,半圆弯拉试验),来分析温度与加载速率对破坏荷载和断裂能的影响,研究结果表明:当试验温度保持恒定时,试件的最大破坏荷载随着加载速率的增大而增大,试件的断裂能与加载速率呈负相关;当加载速率保持不变时,试件的最大破坏荷载将随着温度的升高而降低,试件的断裂能与试验温度呈正相关;该试验所需装置简单、试件制作方便、价格低廉,可以作为沥青混合料抗裂设计的标准试验方法。此外,运用ABAQUS有限元软件模拟试验过程并进行参数敏感性分析,将数值模拟结果与试验结果对比,验证了采用断裂能评价高黏弹性沥青砂抗裂性能的有效性。

The theory of fracture energy is used to study the anti-cracking performance of high viscoelastic tar sand. The semi-circular bending test is carried out at different temperatures and loading rates to analyse the influence of temperature and loading rate on failure load and fracture energy. The result shows that （ 1 ） when the test temperature is constant, the maximum failure load of specimen increases as the loading rate increases, and the fracture energy of the specimen reduces as the loading rate increases; （2） when the loading rate is constant, the maximum failure load of specimens reduces as the temperature increases, and fracture energy increases as the test temperature increases. The needed test device is simple, and the test specimen is easy to manufacture and cheap, thus, it can be used as a standard test method for crack resistance design for asphalt mixture. Besides, the parameter sensitivity analysis is conducted by using ABAQUS finite element software. The comparison of the results of experiment and numerical simulation verified the effectiveness of using fracture energy to evaluate the anti-cracking performance of high viscoelastic tar sand.