铁矿渣路基填料碾压破碎机制数值分析

Numerical Analysis of Crushing Mechanism of Iron Slag as Subgrade Filling under Rolling Compaction

研究铁矿渣路基填料颗粒碾压破碎机制,为确定铁矿渣路基填料碾压工艺参数提供科学依据。采用离散元软件PFC建立铁矿渣路基填料颗粒族碾压破碎的模拟方法,系统分析碾压破碎的影响因素及其引起的路基填料孔隙率、沉降的变化特征。铁矿渣路基填料初始孔隙比的增大、松铺厚度的减小以及碾轮直径的增大均会显著提高颗粒族碾压破碎率。大、小直径碾轮碾压作用下铁矿渣颗粒族破碎率增大引起的孔隙率下降的响应规律差异性较小,而导致的沉降增大的变化特征明显不同。采用大直径碾轮机械施工有利于提高压实施工效率和控制工后沉降。

In order to provide scientific basis for determining the rolling construction parameters of iron slag as subgrade filling,the particle crushing mechanism of iron slag as subgrade filling is studied.The discrete element software PFC is used to establish the simulation method of particles crushing under rolling compaction,and the influencing factors of particles crushing and the variation characteristics of porosity and settlement of subgrade filling caused by particles crushing are systematically discussed.The numerical results indicate that the particles crushing rate of iron slag used as subgrade filling can be significantly improved by the increase of the initial pore ratio,the decrease of the filling thickness and the increase of the roller diameter.Under the rolling compaction action of large and small diameter roller,the decreasing response of subgrade filling porosity caused by the increase of the particles crushing rate of iron slag is less different,but the increasing characteristics of settlement are obviously different.The use of machinery with large diameter roller in rolling construction is beneficial to improve the working efficiency and control the post construction settlement.