连续箱梁、多柱框架墩盖梁预应力次内力对比分析研究  

Comparative Analysis and Research on the Prestressed Secondary Internal Forces of Continuous Box Girders and Multi-column Frame Pier Cap Beams

作　　者：林曾 LIN Zeng(College of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092

出　　处：《广东公路交通》2025年第1期44-48,59,共6页Guangdong Highway Communications

摘　　要：本文以对称两跨连续箱梁、三柱框架墩常规矩形盖梁、三柱框架墩隐盖梁为实例,阐述了连续箱梁、多柱框架墩盖梁预应力次内力的产生过程,并通过对三者进行对比,揭示了主梁或盖梁预应力次内力产生的机理,最后提出了减小预应力次内力的策略。研究结果表明,预应力次内力对结构总效应的影响较大;连续箱梁、多柱框架墩常规矩形盖梁的预应力次弯矩为正,多柱框架墩隐盖梁的预应力次弯矩为负;为减小预应力次内力,连续箱梁、多柱框架墩常规矩形盖梁的预应力筋在梁跨中处宜设置减小凹形竖弯、远离盖梁底缘线形,多柱框架墩隐盖梁则相反。本研究成果可为连续箱梁、多柱框架墩盖梁预应力筋设计提供一定的参考。This paper described the generation of prestressed secondary internal forces using the practical engineering examples,including double-span continuous box girder,three-column frame pier conventional rectangular cap beam and three-column frame pier invisible cap beam.Through comparative analysis,the mechanisms of prestressed secondary internal forces of main girder in continuous box girders and cap beam in multi-columu pier were revealed.Strategies to reduce the prestressed secondary internal forces were proposed.The results indicated that the prestressed secondary internal forces have a significant effect on the overall structural response.The prestressed secondary bending moment is positive for continuous box girders and multi-colum frame pier conventional rectangular cap beams,but negative for the invisible cap beams of multi-colum frame piers.To reduce the prestressed secondary internal forces,the prestressed tendons mid-span arrangement in continuous box girders and multi-colum frame pier conventional rectangular cap beams should minimize vertical bending and be positioned away from the bottom edge of the beam.Multi-colum frame pier invisible cap beams are exactly on the contrary.Therefore,these findings provide valuable reference criteria for prestresses tendon design of continuous box girders and multi-column pier cap beams.

关 键 词：连续箱梁 多柱框架墩常规盖梁 多柱框架墩隐盖梁 预应力次内力 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]