某在役钢筋混凝土刚架拱桥加固研究

发布时间：2018-01-21 16:15

本文关键词： 刚架拱桥主拱肋横系梁微弯板加固　出处：《广西大学》2014年硕士论文　论文类型：学位论文

【摘要】：本文以广西钦州永福大桥加固工程为研究对象,对该桥的主拱肋、横系梁和微弯板的加固方法进行深入的分析。加固后的成桥荷载试验表明,结构承载力及动力稳定稳定性能均达到预期效果。采用的加固方法具有施工工期较短,不影响交通,造价合理等优点。本文主要研究成果如下： (1)针对主拱肋局部较易出现裂缝的特点,研究主拱肋粘贴钢板加固法,采用有限元软件对主拱肋粘贴钢板加固前后的应力变化计算分析,结果表明粘贴钢板对主拱肋不同加固部位的加固效果有明显差异；同时粘钢厚度的变化对各部位的加固效果影响不同,实际加固中应根据加固部位选取适宜的钢板厚度。 (2)针对该桥横向联系薄弱、整体刚度差的特点,研究横系梁加固方法,采用ANSYS软件对横系梁连接处的损伤模拟及横系梁附加型钢加固法加固后的动力特性变化计算分析,结果表明,附加型钢法可以较好改善刚架拱的动力性能；与常规的加固法计算对比分析,表明其加固效果次于增大截面法而优于节点包钢法,综合分析,附加型钢法是刚加拱桥横系梁加固的优选方案。 (3)针对桥面微弯板的承载力不足的特点,研究微弯板加固法,采用二次分析法计算微弯板曲面型钢加固法加固后的受力状态,结果表明曲面型钢可以有效改善微弯板应力状态；理论值与实测值对比分析表明型钢梁与微弯板形成组合结构,改善了微弯板的受力,加固后结构受力性能优良；与常规的加固法计算对比分析,表明其对微弯板应力改善效果介于增大加劲肋法与锚喷混凝土加固法之间；但其微弯板加劲肋处的应力相对较大,采用该法时建议对微弯板加劲肋采取防裂措施。 (4)通过计算分析不同荷载布置工况对该桥的稳定性的影响,结果表明加固后可以有效改善桥梁的偏载效应,即提高偏载作用下的稳定性能。 (5)静力试验分析表明,加固后桥梁的刚度、强度满足要求,整体桥梁处于弹性受力状态,承载力满足要求；动力试验分析表明,此次加固对该桥的整体刚度的提高效果明显,桥梁横向联系在加固后得到明显改善,说明采用的加固方法是可行的,达到了预期效果。本文的研究成果为在役钢筋混凝土刚架拱桥的加固提供了对比数据参考,也为类似桥型的加固提拱参考借鉴。
[Abstract]:In this paper, the reinforcement project of Yongfu Bridge in Qinzhou, Guangxi is taken as the research object, and the reinforcement methods of the main arch rib, transverse beam and micro-bending plate of the bridge are deeply analyzed. The structural bearing capacity and dynamic stability are expected. The reinforcement method has the advantages of short construction period, no impact on traffic, reasonable cost and so on. The main research results of this paper are as follows: 1) according to the characteristic that the main arch rib is prone to crack, the paper studies the reinforcement method of the main arch rib with steel plate, and uses the finite element software to calculate and analyze the stress change before and after the main arch rib is bonded with the steel plate. The results show that there are obvious differences in the reinforcement effect of the main arch rib with the sticking steel plate. At the same time, the influence of the thickness of bonded steel on the reinforcement effect is different, so the appropriate thickness of steel plate should be selected according to the strengthening position in practice. 2) in view of the weak transverse connection and the poor overall stiffness of the bridge, the reinforcement method of the transverse tie beam is studied. The ANSYS software is used to simulate the damage at the joint of the transverse beams and the dynamic characteristics of the beams strengthened by the additional section steel are calculated and analyzed. The results show that. The dynamic performance of rigid frame arch can be improved by adding steel. Compared with the conventional reinforcement method, the results show that the reinforcement effect is inferior to that of the increasing section method and is better than that of the nodal steel-clad method. In the comprehensive analysis, the additional steel method is the optimal scheme for strengthening the crossbeam of the rigid-arch bridge. 3) in view of the insufficient bearing capacity of the micro-bending slab on the bridge deck, the reinforcement method of micro-bending plate is studied, and the stress state of the curved steel reinforcement method of the micro-bending plate is calculated by using the quadratic analysis method. The results show that curved steel can effectively improve the stress state of micro-bending plate. The comparison between the theoretical value and the measured value shows that the composite structure is formed between the steel beam and the micro-bending plate, which improves the force of the micro-bending plate, and the mechanical performance of the strengthened structure is good. Compared with the conventional reinforcement method, the results show that the effect of improving the stress of micro-bending slab is between the stiffening stiffener method and the bolting and shotcrete reinforcement method. However, the stress at the stiffening rib of the micro-bending plate is relatively large, so it is suggested that anti-crack measures should be taken for the stiffening rib of the micro-bending plate. 4) the influence of different load arrangement conditions on the stability of the bridge is analyzed. The results show that the strengthened bridge can effectively improve the eccentric load effect of the bridge, that is, to improve the stability performance of the bridge under the eccentric load. 5) the static test results show that the stiffness and strength of the strengthened bridge meet the requirements, the whole bridge is in an elastic stress state, and the bearing capacity meets the requirements. The dynamic test results show that the effect of this reinforcement on the overall stiffness of the bridge is obvious, and the transverse connection of the bridge is obviously improved after reinforcement, which shows that the reinforcement method is feasible and achieves the expected effect. The research results of this paper provide a reference for the reinforcement of reinforced concrete rigid frame arch bridge in service, and also for the similar bridge type reinforcement and arch lifting reference.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.72

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