关键词: 堆石料, 颗粒形状, 破碎强度, 尺寸效应, Weibull统计, 统计分析

Abstract: A large number of particle crushing test results show that there is a noticeable size effect on the particle crushing strength. The particle crushing strength decreases with the increase of particle size. However, the influence of particle shape on the size effect of particle crushing strength is still unclear. In this paper, particle scanning, particle shape analysis, and single particle compression test of sand-gravel and limestone mixture of Dashixia rockfill dam are carried out. The sphericity and convexity of sand-gravel are larger than those of the limestone mixture. The particles of sand-gravel tend to be round, while the particles of limestone mixture are angular. The test results show that the crushing strength of both kinds of rockfill particles exists noticeable size effect. The applicability of different strength size effect models is then evaluated. Comprehensive analysis of the test results together with the data collected from literature shows that the particle shape has a significant influence on the size effect of the particle crushing strength. The more irregular the particle shape is, the smaller the Weibull modulus of the particle crushing strength is, and the more obvious the size effect of the particle crushing strength is.

Key words: rockfill, particle shape, crushing strength, size effect, Weibull statistical, statistical analysis