Experimental investigation on the impact force of the dry granular flow against a flexible barrier

To reveal the composition and distribution of the impact force of the dry granular flow against a flexible barrier, five groups of physical experiments in different slope angles have been carried out. The flow velocities, flow heights and tensile forces of the cables were measured using the high camera and the load cells. Then we developed a model to calculate the total impact force of the dry granular flow against the barrier based on the tensile force of each cable. The results show that the main components the distribution of the maximum impact force vary with the pileup characteristics of the dead zone. The distributions of the maximum impact force change from linearity to nonlinear with the increase in the proportion of the impact force of flowing layer in the maximum impact force. The hydro-static model, the hydro-dynamic model and the limit equilibrium method were using for the estimation of the maximum impact force, respectively. Compared with the estimated results, the hydro-static model is more suitable for estimating the maximum impact force of the dry granular flow when the pileup height is five times greater than the flow height. The empirical static coefficients have close relationship with the ratio of the pileup length to the pileup height.