下承式系杆拱桥吊杆更换过程的受力分析  

Study on the Force Analysis of Large-span Under-bearing Tie-arch Bridge during the Replacement of Rods

作　　者：卢小明 Lu Xiaoming(Nanchang Highway Development Center,Nanchang,Jiangxi 330038)

机构地区：[1]南昌市公路事业发展中心,江西南昌330038

出　　处：《现代工程科技》2024年第13期9-12,共4页Modern Engineering Technology

摘　　要：早期修建的下承式系杆拱桥受当时技术水平、材料质量及施工质量等因素的影响,随着桥梁运营时间的增加,拱桥吊杆的安全性和可靠性逐渐降低,因此需要及时更换达到设计寿命的吊杆。以某主跨为238m的大跨径钢管混凝土提篮拱桥为例,针对系杆拱桥吊杆更换过程进行受力分析,以得到更好的施工控制策略,分析结果表明:①在吊杆更换施工过程中,临时兜吊内力施工误差为2%时,施工过程中的桥面变形可控制在1.5cm以内,当临时兜吊内力施工误差为5%时,施工过程中的桥面变形达到了2.6cm以内,吊杆张拉力误差越大,桥面变形越大;②在吊杆更换施工过程中,当临时兜吊内力施工误差为5%时,桥梁应力及临时兜吊应力均能满足要求;③建议吊杆更换施工过程中,临时兜吊内力转移时严格控制施工误差在2%以内。永久吊杆与临时兜吊之间的吊杆内力转移过程中,加强监测相邻吊杆处桥面标高变化,使其变化在设计控制范围内。The early construction of through type tied arch bridges was influenced by factors such as technological level,material quality,and construction quality at that time.With the increase of bridge operation time,the safety and reliability of arch bridge suspension rods gradually decreased.Therefore,it is necessary to replace the suspension rods that have reached the design life in a timely manner.This article takes a large-span steel-concrete basket arch bridge with a main span of 238m as an example to analyze the stress during the replacement process of the suspension rods of the tied arch bridge,in order to obtain better construction control strategies.The analysis results show that:①during the replacement construction process of the suspension rods,when the temporary suspension internal force construction error is 2%,the bridge deck deformation during the construction process can be controlled within 1.5 cm.When the temporary suspension internal force construction error is 5%,the bridge deck deformation during the construction process reaches within 2.6 cm.The larger the tension error of the suspension rods,the greater the bridge deck deformation;②During the replacement construction process of the suspension rod,when the construction error of the temporary suspension internal force is 5%,both the bridge stress and the temporary suspension stress can meet the requirements;③It is recommended to strictly control the construction error of temporary suspension internal force transfer during the replacement of suspension rods within 2%.During the internal force transfer process between permanent suspension rods and temporary suspension rods,strengthen monitoring of changes in bridge deck elevation at adjacent suspension rods to ensure that these changes are within the design control range.

关 键 词：下承式系杆拱桥 吊杆 更换施工 拱肋变形 桥面变形 结构应力 

分 类 号：U448.21[建筑科学—桥梁与隧道工程]