Experimental investigation of maximum impact force exerted by dry granular flows on a rigid barrier

Rigid barriers are protective structures widely used in mountainous regions to resist the destructive impacts of dry granular flows originating from shallow landslides or collapses. The determination of the maximum impact force exerted by dry granular flows is crucial in designing rigid barriers. In this study, we conducted laboratory tests in which we examined the weight and particle shape of dry granular flows, as well as the drop height, incident angle, and thickness of the rigid barrier, to investigate the impact force on the rigid barrier. The results indicated that the strongest impact was concentrated at the centre of the rigid barrier, particularly in the lower centre area of the barrier. A new approach is proposed to estimate the maximum impact force on rigid barriers exerted by dry granular flows. In addition, a new impact equation for calculating the maximum impact force that explicitly considers the effects of rigid barrier structural properties on the impact dynamics based on the modulus, Poisson's ratio, and thickness and the particle shape effects based on different shape coefficients is proposed. Based on this new approach, agreement between the prediction results and the observation results was obtained.