预应力混凝土连续箱梁新增预应力加固设计与监测分析  

Design and Monitoring Analysis of Prestressed Concrete Continuous Box Girder Reinforcement with Additional Prestressing

作　　者：严永阳 万燕昌 YAN Yongyang;WAN Yanchang(CCCC Second Highway Consultants Co.,Ltd.,Wuhan,Hubei 430052,China)

机构地区：[1]中交第二公路勘察设计研究院有限公司,湖北武汉430052

出　　处：《黑龙江交通科技》2024年第11期115-119,共5页Communications Science and Technology Heilongjiang

摘　　要：针对变截面预应力混凝土连续箱梁出现密集型底板横向、L型、U型受力裂缝,提出了“新增箱外整联体内长束+箱内局部体外短束”的加固处置方案。在加固施工期以及加固后运营期对体外束索力、关键截面应变及挠度进行监测,结果表明,新增预应力加固后,左幅第2跨梁底应力状态得到有效改善,桥梁实际承载能力得以提升;在加固后运营期,体外索力、关键截面挠度及应变总体变化较平稳,无明显不可逆单向变化趋势,结构整体工作性能良好。In view of variable section prestressed concrete continuous box girder with transverse,L-shaped and U-shaped stress cracks,the reinforcement and treatment scheme of"adding a long prestress inside the box and a short prestress outside the box"is proposed.The external cable force,critical section strain and deflection are monitored during construction period and operation period after reinforcement.The results show that the bottom stress state of the second span beam on the left is effectively improved after the addition of prestressed reinforcement,and the actual bearing capacity of the bridge is increased.During the operation period after reinforcement,the overall changes of external cable force,key section deflection and strain are stable,and there is no obvious irreversible unidirectional change trend,and the overall working performance of the structure is good.

关 键 词：预应力混凝土连续箱梁 新增预应力 桥梁加固 运营期监测 

分 类 号：U442[建筑科学—桥梁与隧道工程]