An novel energy dissipator with self-recovery capability after deformation for structurally energy-dissipating rock-shed

The performance of a structurally dissipating rock-shed (SDR) depends largely on the capacity of its energy dissipators. At present, most energy dissipators are made of metals, which dissipate energy by unrecoverable plastic deformation. Therefore, they are not able to recover their energy-dissipation capacity after deformation under rockfall impact. However, a rockfall usually disintegrates into pieces when it rolls down from a higher position and results in multiple rockfall impacts. An energy dissipator with self-recovery capability is therefore more suitable for ensuring the safety of SDRs. Replacing metal with polyurethane (a hyperelastic material with remarkable self-recovery capability) can provide self-recovery capability for energy dissipators, making them more suitable for resisting multiple rockfall impacts. In this work, polyurethane was manufactured into two types of energy dissipators: cylindrical and cubical. Full-scale falling rock impact tests and dynamic numerical simulations were conducted to study the mechanical response of the energy dissipators. In addition, in order to ensure the accuracy of the simulation, the dynamic mechanical properties of the polyurethane were tested and its dynamic constitutive model was established. The experimental and simulation tests have clarified the advantages of the polyurethane energy dissipator. We also summarized the practical considerations in the design of energy dissipators.