氯盐环境下GFRP筋-海砂混凝土深受弯构件承载性能研究OA

In coastal and marine engineering,using sea sand to replace river sand can reduce the costs associated with cross-regional transportation of river sand and help protect terrestrial ecosystems.Coupled with the use of glass fiber reinforced polymer(GFRP)bars instead of steel reinforcement,it effectively resolves the issue of chloride ion corrosion in sea sand.For the common bent caps and other deep flexural members in offshore bridges,30 GFRP bar-sea sand concrete deep flexural members were fabricated,and their load-bearing performance was tested after immersion in a chloride environment for different durations,including failure modes,deflection,cracking,and ultimate load capacity.The results show that chloride salt immersion changes the failure mode of GFRP bar-sea sand concrete deep flexural members from concrete crushing to shear failure.As the immersion time increases,the cracking load of the members increases,the ultimate load capacity of the members decrease,the cracks number of the members gradually reduces,and the maximum deflection value of the members increase.Based on the test results,the existing code formula for calculating the load-bearing capacity of reinforced concrete deep flexural members is modified by introducing the GFRP bar reduction factor index.The modified formula can well predict the ultimate load capacity of GFRP bar-sea sand concrete deep flexural members after immersion in a chloride environment.