Key mechanical component properties for a high-ductility energy-absorbing rockfall barrier
-
Graphical Abstract
-
Abstract
Traditional passive flexible protection systems often fail under high-energy rockfall impacts, leading to structural destruction and casualties. To address this critical limitation, this study develops a novel high-ductility energy-absorbing (HDEA) system incorporating negative Poisson's ratio (NPR) materials. The mechanical performance of the HDEA system was comprehensively evaluated through an integrated methodology comprising static/dynamic tests, finite element simulation, and field monitoring. Quasi-static tensile and drop hammer impact tests were conducted on conventional positive Poisson's ratio (PR) steel and NPR materials. The NPR material exhibits 54.4%-68.8% higher tensile strength and 1.04-1.31 times greater elongation at break than the PR material. Dynamic tests reveal the NPR cable achieves 44.29% lower single-impact deformation with 1.39 times higher cumulative impact deformation versus the PR counterpart. These results indicate that the NPR material breaks the strength-ductility trade-off, equipping the cable with both high impact resistance and exceptional energy absorption. The fastener transits from plastic deformation to fracture under extreme conditions while the NPR cables retain integrity. This contrasting behavior validates a deliberate failure hierarchy, where the fastener acts as a sacrificial component, thereby preserving the integrity and reusability of the NPR cable. Slip resistance tests verify an anti-slip capacity exceeding 350 kN. This confirms a robust interfacial bond between the cable and fastener, which is critical for ensuring the coordinated deformation of the entire interception net under rockfall impact. Field implementation demonstrates the HDEA system withstands daily average of 3 rockfall impacts with 2000 J mean impact energy while maintaining structural integrity. This study pioneers the application of NPR materials in rockfall protection systems, providing a groundbreaking solution for mitigating high-energy rockfall hazards.
-
-