摘要
某预应力混凝土连续刚构桥(69 m+120 m+69 m)在中跨合拢段施工完成后,跨中底板出现大面积空洞和底板崩裂等病害。首先通过对崩裂区域进行试验检测,结合钢束是否超限上浮的荷载效应和相应抗力的计算分析及桥梁设计、施工中的不足,分析得到了底板崩裂的主要原因。然后基于对结构压应力恢复和储备的目标,对比分析了部分拆除重建、对称顶升边跨支座、中跨跨中配重、抽换旧钢束重新穿索张拉和增加体外索5种加固方法,在不拆除桥梁原结构的前提下用科学合理的加固措施完成了桥梁维修加固,保证了该桥梁后续运营安全。
After the completion of the construction of the mid-span closed section of a prestressed concrete continuous rigid frame bridge(69 m+120 m+69 m),large-area cavity and bursting crack in bottom slab occurred in the mid-span bottom slab.Firstly,the main causes of bursting crack in bottom slab are analyzed by testing the cracking area,combining with the calculation and analysis of the load effect of the steel bundle over-floating and the corresponding resistance,and the shortage in bridge design and construction.Then,based on the goal of recovery and reservation of the compressive stress of the structure,five reinforcement methods are compared and analyzed,including partial demolition and reconstruction,symmetrical lifting side span support,mid-span counterweight,replacing old steel bundles,re-piercing cable tension and adding external cables,the bridge's maintenance and reinforcement is completed with scientific and reasonable reinforcement measures without dismantling the original structure of the bridge,to ensure the bridge's subsequent operation.
作者
刘坤
李睿
周永兵
李定美
杨晶晶
LIU Kun;LI Rui;ZHOU Yong-bing;LI Ding-mei;YANG Jing-jing(The Faculty of Civil Engineering and Mechanics,Kunming University of Science and Technology,Kunming 650504,Yunnan,China;Qujing Highway Bureau,Qujing 655000,Yunnan,China;Yunnan Ruide Road Bridge Engineering Design Co.,Ltd.,Kunming 650500,Yunnan,China)
出处
《筑路机械与施工机械化》
2020年第8期56-60,65,共6页
Road Machinery & Construction Mechanization
基金
国家自然科学基金(51568029)
云南省交通厅科技开发项目(云交科2013(c)08)。
关键词
连续刚构桥
跨中
底板崩裂
加固方法
continuous rigid frame bridge
mid-span
bursting crack in bottom slab
reinforcement method
