原级配和湿筛混凝土断裂性能差异的骨料含量效应

为了研究骨料含量对水工大骨料混凝土湿筛前后力学性能差异的影响，利用细观有限元方法模拟了原级配与湿筛混凝土单轴拉伸作用下的断裂过程，并分析了在原级配试件骨料含量分别为40%,45%和50%的情况下，原级配和湿筛混凝土拉伸断裂性能差异的变化规律，在此过程中还采用了Monte Carlo模拟方法消除了混凝土细观结构随机性带来的影响。分析结果表明：在骨料含量逐步提高的情况下，原级配混凝土与湿筛混凝土力学性能的差异出现了明显变化，弹性模量的比值随之相应增大，峰值应力的比值基本保持不变，峰值应变及断裂能的比值随之趋于减小。

Effect of aggregate contents of original-graded and wet-screened concrete on concrete fracturing behavior

In order to study the effect of aggregate content on the mechanical properties of concrete before and after wet screening, the fracture process between original-graded and wet screen concrete under uniaxial tension was simulated by meso-finite element method. The variation of tensile fracture properties between original gradation and wet screen concrete was analyzed when the original aggregate content was 40%, 45% and 50%, respectively. In this process, Monte Carlo simulation method was used to eliminate the influence of randomness of concrete meso-structure. The results showed that when the aggregate content increases gradually, the difference of mechanical properties between the original graded concrete and wet screen concrete changes obviously, the ratio of elastic modulus increases correspondingly, the ratio of peak stress remains basically unchanged, and the ratio of peak strain and fracture energy tends to decrease.