Abstarct: Solid particle transport in fluid flow is a common phenomenon in nature and its most common example in hydraulic science is sediment transport in rivers. In a channel with a bed of sedimentary material, at very low flow rates the bed particles have no movement and remain in place. As the discharge increases, the bed particles begin to move, this moment is called the sediment particle movement threshold. In this study, using a numerical model baxsed on OpenFOAM software, two-dimensional simulation of sediment particle transport individually and collectively in turbulent flow is investigated. The approach adopted in the simulation is Eulerian-Lagrangian in which the continuous phase is simulated by Eulerian finite volume method and the sediment particles are Lagrangian and particle tracking. In the present model, the effect of fluid on particle, particle on fluid as well as the forces that precipitate sediment particles are considered. In order to consider the impact of sediment particles on each other, a sediment particle collision model is used which has lower computational cost than the existing collision model. The parameters affecting sediment flow and particle have been verified and compared with analytical and experimental results of different researchers. Then the rotation and saltation of a sediment particle were simulated on a rough bed and the flow and particle velocities, forces applied to the particle, and the horizontal and vertical velocity of the saltation were discussed. Also the threshold of group motion of sediment particles in the form of shear stress, critical velocity and two other criteria have been compared with the results of different researchers and a relationship has been proposed for critical threshold of particle motion. Finally, the parameters affecting the critical shields, including particle Reynolds number, longitudinal bed slope and repose of angle of particles are discussed. The results of this study show that the present Eulerian-Lagrangian model has been able to simulate these phenomena with good accuracy and to be used for similar problems.