盐雾环境下一字型短肢RC剪力墙抗震性能试验

EXPERIMENTAL STUDY ON ASEISMIC BEHAVIOR OF SHORT-PIER RC SHEAR WALLS IN SALT-FOG ENVIRONMENT

盐雾环境下氯离子侵蚀对既有RC结构抗震性能具有较大影响,采用人工气候实验方法模拟近海盐雾环境对8榀剪跨比为2.14的一字型短肢RC剪力墙进行加速腐蚀,达到预期腐蚀目标后对其进行拟静力加载试验,重点研究盐雾腐蚀程度对剪力墙试件承载力、变形、强度衰减、刚度退化、耗能等指标的影响以及不同设计参数对锈蚀试件抗震性能的影响。试验结果表明:钢筋锈蚀对RC剪力墙抗震性能影响较大,随锈蚀程度增加,试件逐渐以剪切破坏为主的弯剪破坏向以弯曲破坏为主的弯剪破坏转变,试件的承载力不断减小,变形能力变差,强度衰减和刚度退化不断加剧,耗能能力变差;但是,横向分布钢筋减小可以有效改善锈蚀RC剪力墙的变形能力;同时,限制剪力墙的轴压比也可以有效改善锈蚀RC剪力墙试件的抗震性能。

The chloride ion corrosion has a great influence on the seismic performance of existing RC structures in salt fog environment.The artificial climate experiment method is used to simulate an offshore salt fog environment to accelerate the corrosion of 8 short-pier RC shear walls with a shear span ratio of 2.14.After achieving the anticipated corrosion target,pseudo-static loading tests are carried out,focusing on the influence of salt fog corrosion degree on the bearing capacity,deformation,strength degradation,stiffness degradation,energy dissipation and other indicators of the shear wall specimens.And the influence of different design parameters on the seismic performance of corroded specimens are also studied.The test results show that corrosion has a great influence on the seismic performance of RC shear walls.With the increase of corrosion degree,the specimens are gradually changed from shear failure to bending failure;the bearing capacity,deformation capacity and energy dissipation capacity of specimens decreases;and the strength attenuation and stiffness degradation increases.Nevertheless,reducing the transverse distribution of steel bars can effectively improve the deformation capacity of corroded RC shear walls,and limiting the axial compression ratio of shear wall can also effectively improve the seismic performance of corroded RC shear walls.