摘要
采用后张法施工的预制箱梁结构现场安装完成后,梁体的锚下张拉力如达不到设计值,将严重影响运营期间的桥梁结构梁体受力表现。以西石河大桥部分预应力混凝土边梁为例,按照结构内力等效的原则确定试验等效荷载,采用相同跨径的简支梁将试验荷载分三级施加于梁体跨中部位,记录梁体相应测点的应变值,实测跨中1/4截面、1/2截面、3/4截面处的挠度值。同时利用Midas/civil结构分析软件,考虑实际边界条件,模拟计算连续梁预制箱梁结构跨中1/4截面、1/2截面、3/4截面处的挠度值,将现场实测挠度与理论计算挠度进行对比求解结构位移校验系数,并与文献记载中的同类型桥跨结构的结构位移校验系数比较,分析评价锚下张拉力不足对桥梁实际承载能力的影响,对同类型的工程问题解决具有一定的参考价值。
When the precast box girder structure constructed by post-tensioning method is installed on the spot,if the tension force under the anchor can not reach the designed value,it will seriously affect the behavior of the bridge structure during the operation.Taking some prestressed concrete side beams of the West Thach Ha bridge as an example,the test equivalent load is determined according to the principle of structural internal force equivalence,the deflection values of 1/4 section,1/2 section and 3/4 section in the middle span are measured.At the same time,using Midas/civil structural analysis software,considering the actual boundary conditions,the deflection values at 1/4 section,1/2 section and 3/4 section of the middle span of the continuous beam prefabricated box girder structure are simulated and calculated,the measured deflection in situ is compared with the calculated deflection in theory to calculate the structural displacement check coefficient,and compared with the structural displacement check coefficient of the same type of bridge span structure in the literature.
作者
吴志和
Wu Zhihe(Lanzhou University of Resources and Environment,Lanzhou Gansu 730021,China)
出处
《山西建筑》
2024年第8期149-151,共3页
Shanxi Architecture
基金
2022年度兰州市科技局科技发展指导性计划项目:UHPC混凝土现浇湿接缝连接的装配式墩柱工程应用可靠性评价研究(项目编号:2022-5-41)
2023年度兰州资源环境职业技术大学科研能力提升项目(一般项目):空心高墩施工阶段混凝土水化热温度控制及墩身温度裂缝防治措施研究(项目编号:X2023A-14)。
关键词
预制箱梁结构
结构内力等效
试验等效荷载
实际承载能力
precast box girder structure
structural internal force equivalent
test equivalent load
actual bearing capacity
