摘要
高速铁路钢桁加劲连续刚构桥采用"先梁后桁的"的施工顺序,准确预测混凝土收缩、徐变效应对于钢桁加劲连续刚构桥施工至关重要。为了研究混凝土收缩徐变对连续刚构桥变形的影响,本文首先分析了现有的混凝土收缩徐变模型理论;然后以银西高铁莫谷河2号特大桥为研究背景,采用有限元软件建立了该桥梁的实体模型,得到了收缩徐变效应对桥梁挠度的影响程度;最后采用四种不同的收缩徐变模型(GL2000模型、CEB-FIP90模型、ACI209R-92模型、AASHTO模型)进行理论计算并与实测数据进行比较,探讨了理论与实际偏差的原因。研究结果表明:收缩徐变效应对连续刚构桥变形影响较大。在材料参数准确的情况下,有限元模型能较为准确的计算收缩徐变导致的挠度。相比于其他三个计算模型,AASHTO模型的计算结果与实测值吻合较好。由于采用不同收缩徐变模型,变形计算结果差异较大,为保证预测精度,应尽量选取符合当地环境的收缩徐变模型进行计算。
High-speed railway concrete continuous rigid frame bridge with steel truss adopts the construction sequence of"beam first and then truss".It is of great importance to the construction of concrete continuous rigid frame bridge with steel truss to accurately predict the effect of concrete shrinkage and creep.In order to study the influence of concrete shrinkage and creep on the deformation of continuous rigid frame bridge,this paper first analyzes the existing concrete shrinkage and creep model theory.Then taking the mogu river 2 Super Major Bridge of Yinxi high speed railway as the research background,the finite element software is used to establish a solid model of the bridge,and the degree of influence of shrinkage and creep effects on bridge deflection is obtained.Finally,four different shrinkage and creep models(GL2000 model,CEB-FIP90 model,ACI209 R-92 model,and AASHTO model)are used for the theoretical calculation which is compared with the measured data,and the reasons for the deviation between theory and practice are discussed.The research results show that the effect of shrinkage and creep has great influence on the deformation of a continuous rigid frame bridge.In the case of accurate material parameters,the finite element model can accurately calculate the deflection caused by shrinkage and creep.Compared with the other three models,the calculation results of the AASHTO model agree well with the measured values.Bridge deformation calculation results obtained by using different shrinkage and creep models are quite different.To ensure the accuracy of prediction,a shrinkage and creep model that matches the local environment should be selected as far as possible for the calculation.
作者
卢思吉
刘矗东
张志强
孙约瀚
陈文尹
赵兵
LU Siji;LIU Chudong;ZHANG Zhiqiang;SUN Yuehan;CHEN Wenyin;ZHAO Bing(Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,China;The Seventh Engineering Co.,Ltd.of CTCE Group,Hefei 230022,China)
出处
《建筑结构》
CSCD
北大核心
2020年第S01期752-756,共5页
Building Structure
基金
国家重点研发计划(2016YFB1200401)
国家自然科学基金(51878564)
四川省科技计划项目(2018GZ0052)
关键词
收缩徐变
连续刚构桥
有限元
挠度
预测精度
shrinkage and creep
continuous rigid frame bridge
finite element method
deflection
accuracy of prediction
