摘要
为了精确计算徐变的大小,为混凝土结构设计及计算提供依据,采用CEB-FIP90、ACI209、GL-2000模型计算构件理论厚度修正前后的徐变值,构件理论厚度修正后徐变值有变小的趋势,并依据计算结果对现行《公路钢筋混凝土及预应力混凝土桥涵设计规范》JTG3362—2018关于徐变计算的构件理论厚度进行修正。研究了混凝土徐变与配筋率之间的关系,推导配筋率对混凝土构件徐变影响的公式,为了方便工程参照,将公式简化为徐变系数修正表格。徐变发展符合Boltzman叠加原理是目前学术界认可的结论,采用规范方法计算后发现,加载期间荷载变化产生的徐变,采用不同的叠加模式算得的结果有很大差异。
In order to accurately calculate the creep of concrete and provide the basis for design and calculate concrete structure,CEB-FIP90,ACI209 and GL-2000 models were used to calculate the creep values of the component before and after theoretical thickness correction,the after-correction creep value had a tendency to decrease.According to the calculation result,the theoretical thickness of component of creep calculation in JTG3362—2018 Highway Reinforced Concrete and Prestressed Concrete Bridge and Culvert Design Code was revised.This paper studied the relation between creep and reinforcement ratio of concrete,and deduced the formula of influence of reinforcement ratio on creep of concrete component.The formula was simplified to a modified form of creep coefficient for facilitating engineering reference.It has been recognized by the academia that the creep development conforms to Boltzman’s superposition principle,however,after calculating by standard method,the creep caused by load variation during loading had great differences when using different superposition model.
作者
李灿
LI Can(Shanxi Transportation Survey&Design Institute Co.,Ltd.,Taiyuan,Shanxi 030032,China)
出处
《山西交通科技》
2019年第5期21-25,48,共6页
Shanxi Science & Technology of Transportation
基金
山西省交通运输厅科技项目,公路旧桥加宽数值模拟与受力特性研究(No.2016-1-16).
关键词
徐变
配筋
构件理论厚度
叠加原理
混凝土
creep
reinforcement
theoretical thickness of component
superposition principle
concrete
作者简介
李灿(1986—),男,河北石家庄人,工程师,工学硕士,2013年毕业于长安大学桥梁与隧道工程专业。
