This work demonstrates a four-way coupling between computational fluid dynamics (CFD) and discrete element method (DEM) through an open-source CFD–DEM code, focusing on bed-load sediment transport at a particulate scale. The study combines numerical and experimental investigations to provide a comprehensive analysis. Large eddy simulation (LES) turbulent modeling is employed to capture turbulent scales, while interparticle sediment collision is highlighted through four-way coupling. The research showcases the mutual interaction between the fluid and sediment particles, emphasizing the impact of turbulence and near-bed flow velocity on particle motion. The presence of sediment particles in turbulent flows affects the fluid motion and associated turbulent activities. Furthermore, the study reveals the influence of sediment on the turbulent structures in the flow, attributed to momentum exchange between the particle and fluid phases. Fluctuation variations at the location of interacting particles demonstrate this effect.