基于Burgers模型,应用微观力学理论和粘弹性原理,建立了均质粘弹性材料的离散单元模型,对粘弹性材料的蠕变过程进行了数值模拟,并对模拟结果与已有且经过验证的理论公式计算结果作了比较。结果表明,数值模拟结果曲线与B嶝模型的理论蠕变曲线相一致,且数值模拟与解析解的结果整体上基本一致,相比解析解的复杂繁琐,DEM数值模拟是一种更加行之有效的较简单的研究方法。但是,数值模拟的结果在卸载后的部分与解析解不很吻合。总之,DEM数值模拟可以节省大量的室内试验并提高准确性,可用于对粘弹性材料的进一步研究。
According to the micromechanical behavior of viscoelastic materials, a viscoelastic model was developed using a discrete element modeling approach to simulate the performances of the materials. First, viscoelastic mechanical models were introduced, and the Burgers contact model was employed to investigate the viscoelastic performances of the material.Then, the discrete element model of homogeneous viscoelastic materials was established by mieromechanies and viscoelasticity theory and the uniaxial creep tests were simulated. At the end, the results based on the numerical simulations and analytical solutions were compared. It was found that the results from the two approaches agree with each other verywell, and the DEM numerical simulation was more effective and simple. But the results of unloading parts do not coincide with each other very well. In conclusion, numerical simulation by DEM method can be used in further research of viscoelastic materials as less laboratory tests and more accuracy.