混杂纤维混凝土二维随机建模方法

Two-dimensional Stochastic Modeling Methods of Hybrid Fiber Reinforced Concrete

以二维凸多边形骨料混杂纤维混凝土为例,提出骨料间、骨料与纤维间和聚丙烯纤维与钢纤维间的干涉判断方法,构建混杂纤维混凝土的二维随机投放生成算法和随机游走生成算法,并从骨料投放量、试件密实度、纤维分散性以及生成效率等4个方面对比分析两种算法的优劣。编制界面友好的交互式混凝土/纤维混凝土随机生成程序,展现不同骨料形状的钢纤维混凝土、聚丙烯纤维混凝土及混杂纤维混凝土试件投放效果,以验证生成算法的有效性和程序的可执行性。最后建立3种骨料形状的混杂纤维混凝土细观结构有限元模型。结果显示,随机游走生成算法比随机投放生成算法更适合于生成高填充率的混杂纤维混凝土试件,但其纤维分散性则相对较差。

In the case of the two-dimensional HFRC with convex-polygonal aggregates, the interference judgment methods between aggregates, between aggregates and fibers and between polypropylene fibers and steel fibers were pro posed, and then two generation algorithms based on random distribution and random walk were suggested for the two-di mensional HFRC. Meanwhile, the advantages and disadvantages of the two algorithms were compared from four aspects including aggregates quantity, specimen compactness, fiber dispersity and generation efficiency. A use〉friendly interac tive random generation program of plain concrete and fiber reinforced concrete was composed, which illustrated distribu tion effect of steel fiber reinforced concrete （SFRC）, polypropylene fiber reinforced concrete （PFRC） and HFRC with dif- ferent aggregate shapes in order to verify the effectiveness of the two generation algorithms and the program operability. Finally, three meso-structure finite element models of HFRC with different aggregate shapes were built. The experimen tal results show that the generation algorithm based on random walk is more suitable for high fill rate HFRC than the generation algorithm based on random distribution, but its fiber dispersity is relatively poor.