预应力折线形铰接钢拱加固拱桥技术研究

发布时间：2018-01-13 08:22

  本文关键词：预应力折线形铰接钢拱加固拱桥技术研究　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

  更多相关文章： 拱桥加固 预应力铰接钢拱 模型实验 内力优化 抗压承载力

【摘要】：我国有相当部分拱桥，尤其是早期修建的拱桥，由于结构设计上不够完善，未能达到规定要求，以及施工质量不佳等原因，特别当时片面强调大跨径、省材料等因素，致使很多拱桥存在不同程度的病害。然而，在一定时期内，由于财力有限，许多拱桥将继续使用，短时间内不可能全用新桥替换，为保证运营安全，对一些桥梁进行维修加固是难以避免的。桥梁的维修加固具有较大的经济效益，因此，研究拱桥的加固方法，对拱桥进行技术改造，提高其承载能力成了当前公路桥梁建设中急待解决的问题。 预应力折线形铰接钢拱加固拱桥是基于拱桥受力特点提出的一种有效的预应力主动加固方法。该加固技术是针对在役上承式混凝土拱桥，，在原主拱圈下增设铰接折线形钢拱圈，通过在铰接钢拱拱脚部位施加轴向预应力，来达到改善、优化原主拱圈在自重荷载作用下各主要截面（一般拱顶、1/4、3/8、5/8、3/4及拱脚部位等）内力分布（主要是弯矩分布）的目的。通过加固调整、优化实现拱桥主拱圈在恒载作用下的内力重分布，使原主拱圈弯曲能量减少，有利于削减弯矩峰值和平缓变形，最后达到提高其承载和使用性能的目的。 本文以预应力铰接钢拱加固拱桥技术原理为依据，以新疆军民团结桥为工程背景，建立其主拱圈缩尺模型，对比分析了缩尺模型在模拟自重荷载作用下，采用预应力折线形钢拱加固前后各主要控制截面的应变、挠度指标。从加固前后试验拱的应变、挠度值对比可以看出，缩尺模型经加固增强处理后，各控制截面偏心距减小了，主拱圈弯曲能量也有大幅减小。结果说明新增加的钢拱圈能够与实验缩尺模型协调变形，分担部分自重荷载作用效应，减少了缩尺模型拱圈弯曲能和控制截面偏心距，从而提高了拱圈正截面的抗压承载力。 本文最后以渝北龙兴镇石门拱桥为例，采用该加固方法对其加固，并对加固前及加固后的弯矩包络图进行对比，证实使用该预应力折线形钢饺拱加固后使原桥承载力得到提高。该加固技术对改善类似线形不佳或自重内力条件不利的拱桥的承载力和使用性能，效果显著，可广泛应用于实践。
[Abstract]:I owned a considerable part of arch bridge, especially the early construction of the bridge, because the structure design is not perfect, can not meet the requirements, and the poor quality of construction and other reasons, especially when the one-sided emphasis on the large span, factors of materials, resulting in a lot of arch bridges have different degrees of disease. However, in a certain period of time, due to limited financial resources many will continue to use the arch bridge, a short period of time can not fully use bridge replacement, in order to ensure the operation safety of some bridge reinforcement is difficult to avoid. Bridge maintenance reinforcement has great economic benefits, therefore, reinforcement methods of arch bridge, arch bridge to carry out technological transformation, improve the bearing capacity of the urgent to solve the current problems in highway bridge construction.
Prestressed mansard arch reinforcement hinged steel arch bridge is a kind of effective active reinforcement method of prestressed arch bridge. Based on the stress characteristics of the reinforcement technique for in-service deck arch bridge, an articulated folding steel arch in the original arch ring, through the hinged steel arch foot position is applied to improve the axial prestress. The owner, optimization of arch under self weight load under the action of the main section (general 1/4,3/8,5/8,3/4 vault, and the arch part etc.) internal force distribution (mainly moment distribution purposes.) by strengthening the adjustment, optimize internal force of arch ring under constant load redistribution, the main arch bending energy reduction, to reduce the bending moment the peak and the slow deformation, finally to improve the bearing performance and purpose.
In this paper the prestressed steel arch bridge reinforcement technology is based on the principle, to Xinjiang unity bridge as the engineering background, the establishment of the main arch scale model, comparative analysis of the scale model in the simulation of gravity loads, the prestressed concrete steel arch strain, the main control section of the deflection index before and after reinforcement. From the strain before and after reinforcement test of arch deflection, the contrast can be seen, the scale model by strengthening the enhanced after treatment, the control section of the eccentricity is reduced, the main arch bending energy has also greatly reduced. Results show that the new steel arch deformation and experimental scale model of coordination, sharing part of the dead load effect, scale model of arch bending and control the section eccentricity is reduced, thus improving the bearing capacity of normal section compressive arch.
The Shimen Yubei Longxing town arch bridge as an example, using the reinforcement method of the reinforcement, and compares the reinforcement before and after reinforcement moment envelope diagram, confirmed using the prestressed concrete steel arch bridge reinforcement after the dumplings are improved. The carrying capacity of the reinforced technology on bearing capacity and performance, improve the similar linear or poor dead load internal force unfavorable conditions arch effect, can be widely used in practice.

【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.22;U445.72

【参考文献】

中国期刊全文数据库 前1条

1 蒙云;梁传波;戚志河;;复合加固法提高石拱桥承载力在大件运输中的应用[J];重庆交通学院学报;2006年S1期

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