颗粒形状对粒状材料圆柱塌落影响的三维离散元模拟  

Three-dimensional discrete element simulation of influence of particle shape on granular column collapse

作　　者：张成功 尹振宇 吴则祥[4] 金银富 ZHANG Cheng-gong;YIN Zhen-yu;WU Ze-xiang;JIN Yin-fu(College of Civil Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education. Tongji University,Shanghai 200092,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong,China;School of Architecture and Civil Engineering,Wenzhou University,Wenzhou,Zhejiang 325035,China)

机构地区：[1]同济大学土木工程学院,上海200092 [2]同济大学岩土及地下工程教育部重点实验室,上海200092 [3]香港理工大学土木与环境工程学系 [4]温州大学建筑与土木工程学院,浙江温州325035

出　　处：《岩土力学》2019年第3期1197-1203,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.41372285;No.51579179)~~

摘　　要：粒状土经常发生塌落破坏而诱发泥石流、滑坡等自然灾害。现有研究缺乏颗粒形状对粒状土塌落形态的影响分析。利用三维离散元方法,对粒状材料圆柱试样的塌落破坏机制进行了模拟分析。离散元数值模拟考虑了3种典型的颗粒形状:常规的球形颗粒、正四面体形颗粒和长条形颗粒,取相同的颗粒级配,并以同样的方法分别生成同样高径比的试样,然后进行塌落破坏。基于结果对比分析了由不同形状的颗粒组成的圆柱试样的最终塌落高度和跑出距离,并将离散元模拟与室内试验进行了对比。结果表明:利用离散元方法可以很好地重现室内粒状材料圆柱试样的塌落过程;与纯球形颗粒的试样相比,不规则形状颗粒的试样可以降低颗粒的角速度,同时可以保持较大的最终塌落高度和减小最终的跑出距离。Collapse of granular soil often induces natural disasters such as debris flow and landslide. Existing studies lack the influence of particle shape on the collapse morphology of granular soils. In this paper, three-dimensional discrete element method is used to simulate the collapse failure mechanism of granular material cylinder specimens. Three typical particle shapes(spherical,tetrahedral and elongated) are considered in the numerical simulations. For each particle shape, cylinder specimens with the same size and the same grain size distribution are generated using the same method, and then collapse tests are performed. Based on experimental results, the final collapse height and runout distance of cylindrical specimens with different shapes of particles are analyzed and compared with the laboratory test. It can be concluded that the discrete element method can reproduce the collapse process of the granular columns very well. Compared with specimen of pure spherical particles, specimens composed of irregular shape particles can reduce the angular velocity of particles, maintain a larger final collapse height and reduce the final runout distance.

关 键 词：颗粒流 离散单元法 砂土 颗粒形状 微观力学 颗粒接触 

分 类 号：O158[理学—数学]