基于实桥测试的大跨径混合梁钢梁-混凝土梁结合段传力机理

于祥坤¹，赵伟¹，申港¹，王先宣¹，王保群^2*，宋军²，董旭²

1.日照公路建设有限公司，山东 日照  276825；2.山东交通学院交通土建工程学院，山东 济南  250357

摘要：为研究大跨径混合梁钢梁-混凝土梁结合段的传力性能和纵桥向应力传递路径，以韩庄运河特大桥为工程背景，通过实桥测试与数值模拟相结合的方式，分析主梁钢梁-混凝土梁结合段应力分布与传递规律。对钢板和混凝土进行应变监测，获取其应力分布与传递规律；采用软件ABAQUS建立钢梁-混凝土梁结合段精细化有限元计算模型，对比分析实桥数据与计算模型分析结果。结果表明：在钢梁-混凝土梁结合段应力从承压板传递到混凝土梁的过程中，随距承压板距离的增大，应力逐渐减小，混凝土梁段应力最小；承压板的最大应力出现在预应力锚固处，越接近承压板中心和承压板边缘，应力越小；承压板顶部整体应力在吊装阶段较大，底部应力在张拉阶段较大，现场采集数据与有限元模型应力传递规律一致。

关键词：大跨径混合梁；钢梁-混凝土梁结合段；应力传递；承压板；有限元分析；实桥测试

Force transmission mechanism of the joint section of long-span hybrid girder steel concrete beam based on in-situ bridge test

YU Xiangkun¹, ZHAO Wei¹, SHEN Gang¹, WANG Xianxuan¹,

WANG Baoqun^2*, SONG Jun², DONG Xu²

1.Rizhao Highway Construction Co., Ltd., Rizhao 276825, China；

2.School of Civil Engineering, Shandong Jiaotong University, Jinan 250357, China

Abstract: To study the force transmission performance and longitudinal bridge stress transfer path of the large-span hybrid steel-concrete beam joint section, the Hanzhuang Canal Bridge used as the engineering background, a combination of field bridge testing and numerical simulation is used to analyze the stress distribution and transmission law of the main beam steel-concrete beam joint section. The strain of the steel plates and concrete is monitored to obtain their stress distribution and transmission laws; the software ABAQUS is used to establish a refined finite element calculation model of the steel-concrete beam joint section, and the analysis results of the field bridge data are compared with the calculation model. The results show that during the process of stress transmission from the compressive plate to the concrete beam in the steel-concrete beam joint section, as the distance from the compressive plate increases, the stress gradually decreases, and the stress in the concrete beam section is minimal. The maximum stress on the compressive plate appears at the prestressed anchorage, with stress decreasing closer to the center and edge of the compressive plate. The overall stress at the top of the compressive plate is greater during the hoisting stage, while the stress at the bottom is greater during the tensioning stage, and the collected field data is consistent with the stress transmission law of the finite element model.

Keywords: long-span hybrid beam; the joint section of steel-concrete beam; stress transfer; pressure bearing plate; finite element analysis; in-situ bridge test