Experimental and numerical investigations of a novel steel-UHPFRC composite fender for bridge protection in vessel collisions

摘要

Steel fenders are often used in bridge protections to absorb impact energy associated with a vessel collision. However, disadvantages such as susceptibility to corrosion have been evidenced in existing fenders. To this end, a novel fender structure composed of steel and ultra-high performance fiber reinforced concrete (UHPFRC) is proposed, where outer panels as stiff guards are made of UHPFRC that was demonstrated to possess high ductility and impact resistance, and corrugated steel plates are designed as energy-absorbing elements. Four steel-UHPFRC specimens and one specimen composed of steel and reinforced concrete (RC) were tested through drop hammer impact systems. It was found that the crashworthiness of UHPFRC panel was superior to that of RC panel. Relative resistances between the UHPFRC panel and the corrugated steel plate had a significant influence on impact performances of the composite fender. To reasonably evaluate impact performances of the proposed fender, finite element (FE) models were developed and validated by the impact tests. An application study was performed using the validated FE modeling to investigate the applicability of the proposed fender in practice. The proposed fender was demonstrated as being capable of effectively decreasing impact forces and responses of a bridge as well as vessel damage.