关键词: 钙质土, 单颗粒破碎试验, 一维压缩试验, 颗粒粒径, 相对密度

Abstract: At present, many studies have been done on the compression properties of calcareous fine sand. However, there is also calcareous coarse sand extensively existing in practical engineering. Therefore, it is important to investigate the compression characteristics of calcareous coarse sand. In present study, single particle crushing tests and one-dimensional oedometer tests of calcareous coarse sand with a single particle size were carried out using particle strength tester and automatic large-scale consolidation instrument. The effects of particle size and specific gravity on single particle strength and compression properties of calcareous coarse sand were studied. The single particle crushing test results show that the characteristic stress of single particles increases with the increment of specific gravity. The single particle strength, which can be normalized by the characteristic stress of single particles, is effected by particle size greatly. A curve for survival probability of single particle can be created based on a Weibull distribution. The oedometer test results show that the fractal dimension used to describe the gradation of sand after tests increases with the increase of the particle size; and the relationship between the Hardin’s crushing index and the plastic work is a power function. There is an approximate linear relationship between the yield stress of calcareous coarse sand with a single particle size and the characteristic stress of single particles.

Key words: calcareous soil, single particle crushing test, one-dimensional compression test, particle size, specific gravity