高强钢筋实现低配筋铁路桥墩延性抗震研究

我国铁路桥梁目前仍在大量使用只配有护面钢筋的低配筋桥墩,这类桥墩的变形能力差,在地震作用下易发生脆性破坏。为了提高这类桥墩的抗震性能,提出了采用高强钢筋实现低配筋桥墩延性抗震的思路。对1个配置HRBF500钢筋的低配筋桥墩试件进行低周反复荷载试验,研究试件的破坏形态、滞回特性、刚度退化、耗能性能和延性等。结果表明,试件的破坏模式为延性破坏。在试验研究的基础上,进一步分析高强钢筋实现低配筋桥墩延性抗震的机理。

RESEARCH ON REALIZATION OF SEISMIC DUCTILITY BY HIGH STRENGTH REBAR FOR RAILWAY PIERS WITH LOW REINFORCEMENT RATIOS

The railway bridge piers with low reinforcement ratios are still widely used in our country,which have poor deformation capacity and brittle failure mode under earthquake. In order to improve the seismic performance of such a kind of piers,the idea of using high strength rebar to realize seismic ductility for piers with low reinforcement ratios is put forward. A HRBF500 reinforced pier specimen with low reinforcement ratio was tested under low-cycle loading.The failure mode,hysteretic characteristics,stiffness degradation,energy dissipation and ductility of the specimen were studied. The results indicate that the failure pattern of the specimen is ductile failure. Furthermore,the realization mechanism of seismic ductility by high strength rebar for piers with low reinforcement ratios is further analyzed.