摘要
为研究高烈度山区非等高三柱式排架墩的延性抗震性能,本文以某桥梁桥墩为参考进行缩尺比为1∶12的拟静力试验,分析排架墩损伤过程及塑性铰演化机理,得到排架墩剪力-位移滞回曲线以及相应骨架曲线。基于骨架曲线主要特征点,计算排架墩延性系数,分析试件滞回性能、位移延性性能和刚度退化。引入损伤指数的概念,基于排架墩位移延性对抗震性能目标进行量化,建立损伤指数与排架墩抗震性能目标的联系。试验及分析结果表明:高墩和中墩在墩顶及墩底均产生塑性铰,因塑性铰区混凝土剥落、钢筋屈曲发生弯曲破坏,矮墩因较小长细比发生剪切破坏;各墩长细比相差较大,抗推刚度分布极不均匀,造成矮墩提前剪切破坏退出工作,在矮墩失效后结构仍有一定的延性性能;根据性能目标量化结果,损伤指数超过0.35时,试件进入非线性状态,发生微小损伤,损伤指数达到0.64时,试件进入严重损伤阶段。
To study the ductile seismic performance of non-equal height three-column bent pier in steep slope of high intensity mountainous area,a quasi-static test with a scale ratio of 1∶12 was carried out with a bridge pier in China as a reference,the damage process and plastic hinge evolution mechanism of bent pier were analyzed,and the shear force-displacement hysteresis curve and corresponding skeleton curve of bent pier were obtained.Based on the main feature points of the skeleton curve,the ductility coefficient of the bent pier is calculated,and the hysteretic performance,displacement ductility performance and stiffness degradation of the specimen are analyzed.The concept of damage index is introduced,and the seismic performance target is quantified based on the displacement ductility of the bent pier,and the relationship between the damage index and the seismic performance target of the bent pier is established.The test and analysis results show that both the high pier and the middle pier produce plastic hinges at the top and bottom of the pier.Bending failure occurs due to concrete spalling and steel bar buckling in the plastic hinge area,and shear failure occurs in the low pier due to the small slenderness ratio;The slenderness ratio of each pier is quite different,and the distribution of anti-thrust stiffness is extremely uneven,which causes the short pier to withdraw from the work in advance of shear failure,and the structure still has good ductility after the failure of the short pier;According to the quantitative results of the performance target,when the damage index exceeds 0.35,the specimen enters a nonlinear state and minor damage occurs, when the damage index reaches 0.64, the specimenenters a severe damage stage.
作者
何林峰
李睿
杨建荣
罗仕庭
吕雁
贾毅
He Linfeng;Li Rui;Yang Jianrong;Luo Shiting;Lv Yan;Jia Yi(Faculty of Civil Engineering and Mechanics,Kunming University of Science and Technology,Kunming 650500,China;Kunming Engineering Co.,Ltd.,Kunming 650051,China)
出处
《科技通报》
2024年第11期81-87,共7页
Bulletin of Science and Technology
基金
国家自然科学基金项目(52068037)。
关键词
非等高三柱排架墩
拟静力试验
抗震性能
位移延性
性能目标量化
unequal-height three-column bent pier
quasi-static test
seismic performance
displacement ductili⁃ty
quantification of seismic performance objective
