中文摘要：

为获得胶结颗粒材料细观参数对其抗拉性能的影响,基于离散元理论提出一种胶结颗粒材料单轴拉伸试验数值模拟方法。将数值模拟得到的胶结颗粒材料拉伸应力-应变曲线与试验结果进行对比,验证了数值模拟方法的可行性。采用该方法研究了颗粒粘结参数对平行粘结模型数值试样抗拉强度的影响,建立了给定颗粒尺寸和空隙率情况下的胶结颗粒材料抗拉强度数学预测模型,并根据颗粒粘结参数直接估计胶结颗粒材料抗拉强度。研究结果表明：采用平行粘结模型的数值试样能够较为准确地反映胶结颗粒材料的拉伸力学性状;在颗粒尺寸和空隙率不变的情况下,胶结颗粒材料的抗拉强度与粘结半径系数呈二次函数关系;粘结切向强度和粘结法向强度同步线性增大时,抗拉强度线性增大;粘结切向强度小于粘结法向强度时,抗拉强度随粘结法向强度增长的趋势减缓。

英文摘要：

In order to obtain the influence of microparameters on the tensile strength of bonded granular material,a numerical simulation method of uniaxial tensile test for bonded granular material based on discrete element theory was proposed.The validity of the numerical simulation method was proved by comparing the tensile stress-strain curve obtained from the numerical simulation with that from the experimental results.Based on this numerical simulation method,the influence of particle bond parameters on the tensile strength of the numerical specimen used parallel bond model was analyzed.A mathematical prediction model of the tensile strength of bonded granular material with specified particle size and porosity was established,which made it possible to estimate the tensile strength of bonded granular material from particle bond parameters directly.The results show that the numerical specimen used parallel bond model can reflect the tensile mechanical properties of bonded granular material properly.When the particle size and the porosity remain unchanged,the tensile strength of bonded granular material is affected by the parallel-bond radius coefficient in a quadratic way.The tensile strength exhibitslinear increase as the normal and shear strengths of bonds increase synchronous linearly.The growth tendency of the tensile strength of bonded granular material slows down with the increase of normal strength when the shear strength of the bonds is less than the normal strength.