预应力混凝土连续梁桥托梁换柱改造设计  

Design of Beam Underpinning and Column Replacement Reconstruction of Prestressed Concrete Continuous Beam Bridge

作　　者：朱琳 ZHU Lin

机构地区：[1]北京市市政工程设计研究总院有限公司,北京市100082

出　　处：《城市道桥与防洪》2021年第8期168-170,197,M0016,M0017,共6页Urban Roads Bridges & Flood Control

摘　　要：某新建道路设计标准为双向六车道城市主干路,线位布设时需利用既有桥梁预留孔位,桥梁墩位按跨越双向四车道条件布置,预留宽度无法满足新建道路设计需求。为实现新建主干路功能连续,避免形成交通瓶颈,对现有桥梁墩位进行改建分析。改建目标为三跨预应力混凝土连续梁桥中墩之一,位于新建道路机动车道路幅范围,在不影响桥梁承载能力、不改变桥梁受力体系、保证桥梁运营安全、减小现况交通影响的前提下,提出主动、被动两种托梁换柱改造设计方案,并形成具体实施步骤。根据各自设计内容,针对托换方式、沉降控制、主梁受力、工艺难度、承载效果、景观效果、交通影响等具体特点进行综合对比,结合原桥结构体系特点确定最终方案。最后形成一定结论,并对主动托换及被动托换的特点及适用条件给予总结,为后续相近工程设计形成一定借鉴。The design standard of a newly-built road is a two-way six-lane urban trunk road.The reserved holes of existing bridges should be used in alignment layout.The bridge piers should be arranged according to the condition of crossing two-way four lanes.The reserved width cannot meet the design requirements of the new road.In order to realize the continuous function of the new trunk road and avoid the formation of traffic bottleneck,the reconstruction of the existing bridge piers is analyzed.The reconstruction target is one of the middle piers of the three-span prestressed concrete continuous beam bridge,which is located in the motor vehicle road range of the newly-built road.On the premise of not affecting the bearing capacity of the bridge,not changing the stress system of the bridge,ensuring the safety of the bridge operation and reducing the influence on the current traffic,two design schemes of active and passive underpinning reconstruction are put forward,and the specific implementation steps are formed.According to the respective design contents,the underpinning methods,settlement controls,main beam stresses,technological difficulties,bearing effects,landscape effects,traffic impacts and the other specific characteristics are comprehensively compared.The final scheme is determined combined with the characteristics of the original bridge structure system.Finally,a certain conclusion is formed,and the characteristics and applicable conditions of active underpinning and passive underpinning are summarized so as to form a certain reference for the design of the subsequent similar projects.

关 键 词：托梁换柱 墩柱改造 连续梁桥 主动托换 被动托换 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]