锈蚀固端梁动力特性试验研究  

Research on the influence of corrosion on the dynamic characteristics of reinforced concrete fixed-end beams

作　　者：高鹏 周建庭[1] 阳珊清 徐略勤[1] 孙马[1] GAO Peng;ZHOU Jianting;YANG Shanqing;XUE Lüeqin;SUN Ma(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074

出　　处：《混凝土》2020年第9期15-18,共4页Concrete

基　　金：国家重点研发计划(2017YFC0806007);国家杰出青年科学基金(51425801)。

摘　　要：为了探讨固端梁动力特性参数随纵向钢筋锈蚀率的演变规律,制作了目标锈蚀率为0、5%、10%、15%的试验梁,并采用结构动力特性测试方法,测得固端梁在不同锈蚀程度下的自振频率、阻尼比及模态振型。结果表明:固端梁的阻尼比随着纵向钢筋锈蚀程度的增加而逐渐增大;纵向钢筋锈蚀率较小时,其自振频率降幅不明显,随着锈蚀率的增加,自振频率降幅明显增大,当纵向钢筋锈蚀率为5.82%时,固端梁自振频率降幅达到12.58%;固端梁的模态振型因锈蚀程度的递增,损伤后的振型改变越发显著;采用浸泡式电化学加速锈蚀法进行钢筋锈蚀时,纵向钢筋的实际锈蚀率比理论锈蚀率低。In order to investigate the evolution law of the dynamic characteristic parameters of the fixed-end beams with the longitudinal steel corrosion rate,test beams with the target corrosion rate of 0,5%,10%and 15%were fabricated,and the natural frequency,damping ratio and modal mode shapes of fixed-end beams under different corrosion degree were measured by structural dynamic characteristic test method.The results show that the damping ratio of fixed-end beams increases with the increase of corrosion degree of longitudinal reinforcement.When the corrosion rate of longitudinal reinforcement is small,the decrease of natural frequency is not obvious,but the decrease of natural frequency is more significant with the corrosion rate increasing.As the corrosion rate of longitudinal reinforcement is 5.82%,the natural frequency of fixed-end beam decreases by 12.58%.The modal change of fixed-end beams becomes more and more obvious with the increase of corrosion degree.The actual corrosion rate of longitudinal steel bar is lower than that of theoretical corrosion rate with used by the immersion electrochemical accelerated corrosion method.

关 键 词：固端梁 动力特性 电化学加速锈蚀 损伤 

分 类 号：TU528.01[建筑科学—建筑技术科学]