Coarse aggregate are one of the main components of self-compacting concrete (SCC) and the size, shape, and grading of coarse aggregate can lead to different characteristics of SCC. In this paper, the effect of needle-shaped coarse aggregate on SCC flowability is systematically investigated and presented. A new method is proposed to randomly generate SCC with arbitrary aggregate shape and grading. Aggregate shapes are determined and classified by calculating the shape descriptors of aggregate, and thereby, SCC meeting the calculation requirements is generated. Based on this new method of aggregate generation, the discrete element method (DEM) is used to simulate the SCC flow process in L-box test. By continuously adjusting the content of needle-shaped coarse aggregate, the impact of coarse aggregate shape on the SCC flowability is evaluated, and the acceptable range of needle-shaped coarse aggregate content is obtained, which has guiding significance for the actual selection of concrete coarse aggregate.

粗骨料是自密实混凝土（SCC）的主要成分之一，粗骨料的大小，形状和等级可导致SCC的不同特性。本文系统研究了针状粗骨料对SCC流动性的影响。提出了一种新的随机生成具有任意聚集体形状和等级的SCC的方法。通过计算骨料的形状描述符来确定骨料的形状并对其进行分类，从而生成满足计算要求的SCC。基于这种新的聚集体生成方法，离散元素方法（DEM）用于模拟L箱测试中的SCC流动过程。通过不断调整针状粗骨料的含量，评估粗骨料形状对SCC流动性的影响，