基于PFC离散元混凝土路基填料破碎与压实特性分析OA

To investigate the crushing behavior of waste concrete blocks as subgrade fill material during compaction and the impact of different construction techniques on compaction degree,a discrete element software PFC was used to establish a concrete subgrade fill model and conduct compaction simulations.The factors influencing the crushing rate of the fill material(compaction load,number of passes,and spreading thickness)were systematically analyzed,and the effects of varying compaction passes on the compaction degree were examined from a microscopic perspective based on contact force chains and velocity fields.The results indicate that for concrete fill models with spreading thicknesses of 30,40,and 50 cm,the minimum compaction loads required to achieve relatively stable internal crushing rates and porosity were 20,25,and 30 MPa,respectively,with the minimum number of passes being 7,11,and 16.The mechanical strength(uniaxial compressive strength)and structural stability indicators(porosity)of the particle aggregates formed by waste concrete after compaction meet the requirements of subgrade specification fill materials.In practical engineering,the selection of compaction load and compaction passes should comprehensively consider the effects of different spreading thicknesses on crushing rate,porosity,and settlement to improve construction efficiency and reduce costs.