旧桥主梁承载力分析与加固措施  

Analysis of Bearing Capacity of Main Beam of Old Bridge and Reinforcing Measures

作　　者：陈超 刘金修 CHEN Chao;LIU Jin-xiu

机构地区：[1]新疆交通科学研究院有限责任公司,新疆乌鲁木齐830000 [2]新疆交通投资(集团)有限责任公司

出　　处：《内蒙古公路与运输》2023年第2期44-47,52,共5页Highways & Transportation in Inner Mongolia

摘　　要：为解决旧桥主梁承载能力下降快、安全储备小的问题,通过对旧桥进行受力检算和病害分析,提出了主梁抗弯加固设计方案,即跨中底板一定范围内粘贴两道宽度为40 cm的碳纤维布,边梁设置双层,中梁设置单层,在底板纵向碳纤维布端部截断处设置20 cm宽的U型碳布压条,其延伸长度范围内设置4道40 cm的宽U型箍锚固,并于中横隔板两侧分别设置20 cm宽的U型箍碳布。针对部分主梁抗剪不足问题,提出了具体加固措施,从距支点100 cm处开始斜向45°粘贴8 mm厚钢板,每道宽度15 cm,呈非等间距分布粘贴,其中边梁设置13道,中梁设置10道,并与上端粘贴纵向钢板压条予以锚固。结果表明:验算加固后的主梁抗弯和抗剪承载力均满足设计要求,具备一定的安全储备,研究可为同类主梁加固设计、运营管理和养护措施制定等提供参考。In order to solve the problem that the bearing capacity of the main beam of the old bridge declines rapidly and the safety reserve is small,through the force inspection and disease analysis of the old bridge,a design plan for the flexural reinforcement of the main beam is proposed.Within a certain range of the mid-span floor,two layers of carbon fiber cloth with a width of 40 cm are pasted.The side beam is set with double layers,and the middle beam is set with a single layer.A 20 cm wide U-shaped carbon cloth bead is set at the end of the longitudinal carbon fiber cloth of the bottom plate,and four 40 cm wide U-shaped hoops with the extension length for anchoring are set.A 20 cm wide U-shaped hoop carbon cloth is placed on both sides of the middle transverse partition.In view of the lack of shear resistance of some main beams,specific reinforcement measures are proposed.Starting from 100 cm away from the fulcrum,8 mm thick steel plates are pasted at an angle of 45°,each with a width of 15 cm,and are pasted at non-equidistant intervals.Among them,there are 13 side beams and 10 middle beams,and the upper end is pasted with longitudinal steel plate bead for anchoring.The results show that the flexural and shear bearing capacities of the reinforced main beams after checking and calculation meet the design requirements and have certain safety reserves.The research can provide reference for the reinforcement design,operation management and maintenance measures of similar main beams.

关 键 词：正截面抗弯承载力 斜截面抗剪承载力 碳纤维布加固 粘贴钢板 

分 类 号：U445.7[建筑科学—桥梁与隧道工程]