Abstract

It is commonly accepted that remarkable particle breakage starts at a stress level exceeding the yield point on the compression curve and continuously affects the mechanical behavior of granular materials during compression. A series of one-dimensional compression tests on calcareous sands were performed to investigate the evolution of particle breakage during loading and the influence of particle breakage on the compression behavior. It was found that particle breakage of calcareous sand occurred at a relatively low-pressure region and increased linearly with increasing vertical stress before reaching the yield point. For a given void ratio, particle breakage leads to an increase in compressibility and reduction in stiffness during the compression process. However, the rate of particle breakage slows down with linearly increasing compaction energy, and particle breakage would not continue indefinitely. In one-dimensional compression tests, the total amount of particle breakage for a looser specimen is larger at the same vertical stress. The compaction energy method was used to produce pre-crushed materials and quantify the work consumed on specimens. The relationship between particle breakage index and work per unit volume was examined as well, which was independent of the initial void ratio.

摘要

人们普遍认为，显着的颗粒破裂始于压缩曲线上超过屈服点的应力水平，并在压缩过程中持续影响颗粒材料的机械行为。对钙质砂进行了一系列一维压缩试验，以研究加载过程中颗粒破碎的演变以及颗粒破碎对压缩行为的影响。研究发现，钙质砂的颗粒破碎发生在压力相对较低的区域，在达到屈服点之前随着垂直应力的增加呈线性增加。对于给定的空隙率，颗粒破裂导致压缩过程中可压缩性的增加和刚度的降低。然而，颗粒破碎率随着压实能量的线性增加而减慢，颗粒破碎不会无限期地持续下去。在一维压缩试验中，在相同的垂直应力下，较松的试样的总颗粒破碎量较大。压实能量法用于生产预粉碎材料并量化试样上消耗的功。还检查了颗粒破碎指数与单位体积功之间的关系，该关系与初始空隙率无关。