论文标题
随机quasibrittle培养基中的断裂：I。负载容量和断裂过程区域的离散中尺度模拟区域
Fracture in random quasibrittle media: I. Discrete mesoscale simulations of load capacity and fracture process zone
论文作者
论文摘要
提出了用概率中尺度离散模型进行的混凝土骨折的数值模拟。该模型通过将随机位置分配给最大的聚集体来代表材料随机性的重要组成部分。通过导致材料参数通过均匀的随机场随机波动来引入其余部分。通过模型进行的一项广泛的数值研究认为，棱镜在单轴张力中均以固定和旋转的柏拉图，以及带有和不带有凹槽的横梁在三点弯曲中。结果表明（i）自相关长度和（ii）随机场对模型断裂行为的差异的非平地作用。在达到最大载荷时，介绍了峰值载荷的统计数据以及断裂过程区域的大小和形状。断裂过程区域内的局部平均值和最弱的连接被确定为解释报告结果的基本机制。伴侣论文第二部分[64]引入了一个分析模型，能够通过简单地估算以局部强度的移动平均值获得的随机场的极端估计，以预测用概率离散模型获得的峰值载荷的分布。
Numerical simulations of concrete fracture performed with a probabilistic mesoscale discrete model are presented. The model represents a substantial part of material randomness by assigning random locations to the largest aggregates. The remaining part of randomness is introduced by causing material parameters to fluctuate randomly via a homogeneous random field. An extensive numerical study performed with the model considers prisms loaded in uniaxial tension with both fixed and rotating platens, and also beams with and without a notch loaded in three point bending. The results show the nontrivial effect of (i) autocorrelation length and (ii) variance of the random field on the fracture behavior of the model. Statistics of the peak load are presented as well as the size and shape of the fracture process zone at the moment when the maximum load is attained. Local averaging within the fracture process zone and weakest-link are identified as underlying mechanisms explaining the reported results. The companion paper, Part II [64], introduces an analytical model capable of predicting the distribution of the peak load obtained with the probabilistic discrete model via the simple estimation of extremes of a random field obtained as moving average of local strength.
