徐变对大跨度预应力混凝土连续箱梁桥施工线形控制的影响  

Effect of creep on the construction of linear control of large-span prestressed concrete continuous box beam bridge

作　　者：张汉一[1,2] 周凌宇[1] 贺桂超[1] 肖金敏[1,3] 

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中铁四局,江苏苏州215131 [3]长沙市建筑工程安全监察站,湖南长沙410016

出　　处：《铁道科学与工程学报》2012年第5期13-18,共6页Journal of Railway Science and Engineering

摘　　要：徐变对大跨度预应力混凝土连续梁结构变形和内力的影响不容忽略。基于混凝土徐变预测模型,分析C50混凝土徐变系数的变化规律,得出适合于桥梁监控的预测模型,并对一简支梁进行验证,计算结果与实际工程结果较吻合。在此基础上对京沪高铁跨秦淮河特大桥进行施工监控,依据该桥的施工监控方案,对各个施工节段的标高进行测量与控制,该桥的标高监控实践表明:徐变对桥梁结构影响较为显著;GL2000模型、ACI-209R模型和我国04规范具有较高的精度,可满足施工线形达到设计线形要求。The impact that structure deformation and internal forces of large - span prestressed concrete continuous beam by creep cannot be ignored . Based on the creep prediction model of concrete, the variation of C50 concrete creep coefficient was analyzed, and the prediction model suitable for bridge monitoring was derived. Verification on a simply supported beam, the calculated results are in good agreement with those of the actual project. On this basis, construction monitoring of the Beijing--Shanghai high--speed railway crossing Qinhuai river bridge was made. According to the bridge construction monitoring program, the elevation of each construction phase was measured and controlled. The elevation monitoring practice shows that the creep has a significant impact on the bridge structure. The GL2000 model, the ACL -209 model and 2004 specification have high precision, which can satisfy the construction linear and meet the design of linear requirements.

关 键 词：徐变 预应力混凝土连续箱梁 有限元 线形控制 

分 类 号：TU448.1[建筑科学—岩土工程]