基于离散元的新拌混凝土流变性能分析

Rheological Properties Analysis of Fresh Concrete Based on Discrete Element Method(DEM)

针对新拌混凝土的粘性和流动性影响因素,利用离散元方法建立了新拌混凝土的离散元模型,进行了不同级配下混凝土坍落度和不同骨料形状下L箱模拟试验。结果表明:建立的离散元模型模拟新拌混凝土的流变性能是可行的;不同的颗粒集配曲线对混凝土坍落度和扩展度影响较大,集配上限混凝土坍落度和扩展度比集配中线和下限要大;不同的骨料形状对混凝土的流动性也有一定影响,多面体颗粒比球形颗粒模拟的结果更接近实际结果,更能反应实际的流动情况。

In order to study the influence factors of viscosity and fluidity of fresh concrete, different distribution the slump tests and different aggregate shapes L-box tests of concrete are simulated according to established discrete element model of fresh concrete. The test results show that., the established discrete element model is feasible to simulate the rheological properties of fresh concrete,different distribution curves of particles have great influence on slump and slump flow of concrete, and the slump and slump flow of the concrete on upper limit of distribution is greater than that of the middle limit and the lower limit. Different aggregate shapes also affect the fluidity of concrete. The simulation results of polyhedron particles are closer to the actual results than that of spherical particles and polyhedral particles are more capa- ble of showing the actual flow conditions than other kinds of particles.