考虑材料劣化的钢筋混凝土压弯构件承载力演化试验研究  

Experimental Study on Bearing Capacity Evolution of Reinforced Concrete Compression-bending Members Considering Material Deterioration

作　　者：辛景舟 周建庭[1] 周应新 苏欣[1,4] 冉文兴 XIN Jingzhou;ZHOU Jianting;ZHOU Yingxin;SU Xin;RAN Wenxing(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074;Yunnan Investment Group Investment Co.Ltd.,Kunming 650300;Yunnan Wuyi Expressway Co.Ltd.,Chuxiong 675000;Xingtai Polytechnic College,Xingtai 054035)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]云南交投集团投资有限公司,昆明650300 [3]云南武易高速公路有限公司,楚雄675000 [4]邢台职业技术学院,邢台054035

出　　处：《材料导报》2019年第14期2362-2369,2396,共9页Materials Reports

基　　金：国家重点研发计划(2017YFC0806007);国家杰出青年科学基金(51425801);重庆市人工智能技术创新重大主题专项重点研发项目(cstc2017rgzn-zdyfX0029);云南省科技计划项目(2017IB025)~~

摘　　要：拱、柱等压弯构件作为一种基本构件形式,常应用于高层建筑、大型空间结构和大跨桥梁中。随着服役年限的延长,其不可避免地会遭受锈蚀、碳化等。基于结构的安全性角度出发,其承载力的演化一直是学界与工程界最为关注的问题之一。为研究锈蚀对钢筋混凝土(RC)压弯构件极限承载力的影响,本工作以RC拱桥为基本研究对象,设计制作了15片同截面尺寸的RC柱,基于法拉第定律获取锈蚀构件,讨论了初始锈胀裂缝的分布情况,研究了锈胀柱的裂缝发展、跨中变形和应变、极限承载力及破坏形态。基于数字图像相关技术,揭示了锈损RC压弯构件破坏全过程应变场演化规律。结果表明:(1)随着锈蚀率的增加,锈胀裂缝分布范围、宽度、长度呈增长趋势,RC柱纵向/横向刚度降低,压缩位移/挠度增大,承载能力下降,承载力最大下降40%;(2)偏心距较小的锈蚀柱在荷载作用下的截面应变仍基本符合平截面假定,随着偏心距的增大,平截面假定存在失效趋势;(3)锈胀未改变偏压的失效模式,所有压弯构件均为受压侧脆性破坏,锈蚀损伤改变了压弯构件初始偏心距,小偏心构件存在向大偏心破坏演变的可能;(4)因锈胀裂缝影响,横向应变分层明显。本工作系统描述了锈损RC压弯构件承载力演化行为,可为基于等效梁柱法的RC拱桥承载力衰变分析奠定基础。As the basic component,eccentric compression reinforced concrete(RC)members,such as arches and columns are widely used in high-rise buildings,large space structures and long-span bridges.With an extension in service years,eccentric compression RC members inevitably suffer from performance deterioration,the evolution of its bearing capacity has been one of the most concerned issues in the academic and engineering circles.To study the effect of corrosion damage on the bearing capacity of eccentric compression RC members,this work takes the RC arch bridges as the basic research object,fifteen RC columns with the same section size were designed and fabricated.The corrosion components were obtained based on Faraday s law.The distribution of corrosive cracks,the crack development,the displacements and strains,the bearing capacity and the failure patterns were studied.The strain field evolution law was also revealed based on the digital image correlation technology.The findings show that:(1)with the increase of corrosion rate,the distribution range,width and length of rust expansion cracks show an increasing trend,the compression displacement and deflection increase as the longitudinal and transverse stiffness of RC columns decrease,the bearing capacity decreases,and the maximum decrements of bearing capacity is about 40%;(2)the strain of the corroded columns with small eccentricity still accord with plane section assumption,while there is a failure trend for the plane section assumption with the increase of eccentricity;(3)rust expansion does not change the failure mode of eccentric compression members,the failure of the compression-bending members is due to brittle failure of compression side,corrosion damage changes the initial eccentricity,and small eccentric members may evolve to large eccentric failure;(4)the lateral strain field is chaotic,and the stratification is obvious due to the existence of rust and expansion cracks.This work systematically describes the behavior of the bearing capacity evolution of the cor

关 键 词：锈蚀 钢筋混凝土构件 承载力演化 数字图像相关技术 拱桥 

分 类 号：TU375[建筑科学—结构工程] U444[建筑科学—桥梁与隧道工程]