圬工桥加固优化及稳定性研究
发布时间：2018-10-21 15:28
【摘要】：圬工桥在我国存在非常普遍,在70年代以前,我国的桥梁大多都是圬工桥。现在随着经济的不断发展,桥梁运营载荷的不断增加,自然环境的不断影响,地震等自然灾害的破坏等,现存的圬工桥目前普遍存在着承载力不足等现象,甚至有的圬工桥损坏程度过大直至坍塌。因此对圬工桥进行承载力以及抗震的研究有非常重要的意义,对圬工桥进行加固优化研究能为损坏桥梁的加固设计提供有价值的参考依据。在圬工桥的静力分析方面,本文主要对圬工桥的缺陷影响,洪水冲击影响以及极限承载力方面做了详细的分析研究。通过研究发现当圬工桥的缺陷位于拱脚内部时对结构影响最大,缺陷处出现应力集中,应力增大40%左右,因此要坚决避免此类缺陷出现,设计时可以考虑把拱设计成中间薄两端厚的变截面形式。在洪水作用下圬工桥接受冲击的一侧应力减小50%左右,另一侧应力增大6%左右,因此设计时要加强接受洪水冲击一侧的结构强度。本文通过对圬工桥进行几何非线性以及几何材料双重非线性分析发现,圬工桥在双重非线性下的极限活荷载系数是只考虑几何非线性情况下的1/3左右,双重非线性下的结果要与实际情况更为接近,也更为准确。经过研究发现,桥梁荷载横向布置为偏载时,圬工桥的极限活荷载系数要比中载时小4%左右,这说明圬工桥在偏载作用下结构更为不利。在经过不同的加固后,圬工桥结构得到了明显的改善,正常最大位移减小20%左右,极限最大位移减小30%左右。在不同的加固方法中,加肋加固法不仅能节约材料还能有效加固,是最为理想的加固方法。在圬工桥的动力分析方面,本文主要对加固前后的圬工桥进行了不同地震波作用下的地震响应分析。经过研究发现,在不同地震作用下,加固前后圬工桥在横桥方向比较稳定,位移变化仅8%左右;而顺桥向和竖向的位移变化相当剧烈10%~30%不等,说明在进行抗震加固设计时,要加强顺桥向与竖向的抗震设计;所有地震作用下的应力减小变化不大,均在13%左右,这说明加固能够使圬工桥很好地抵抗地震应力的产生,能在地震过程中起到很好的抗震作用。
[Abstract]:Masonry bridges are very common in China. Before 1970s, most of them were masonry bridges. Now with the continuous development of economy, the continuous increase of bridge operation load, the unceasing influence of natural environment, the destruction of natural disasters such as earthquake, the existing masonry bridges are generally lack of bearing capacity and so on. Even some masonry bridges are too damaged to collapse. Therefore, it is of great significance to study the bearing capacity and seismic resistance of masonry bridges. The study of strengthening and optimization of masonry bridges can provide valuable reference for the strengthening design of damaged bridges. In the aspect of static analysis of masonry bridge, the influence of defects, flood impact and ultimate bearing capacity of masonry bridge are studied in detail in this paper. It is found that when the defects of the masonry bridge are located inside the arch foot, they have the greatest influence on the structure, and the stress concentration appears in the defects, and the stress increases by about 40%. Therefore, it is necessary to avoid the occurrence of such defects. In design, the arch can be designed as a variable cross section with thin intermediate ends. Under the action of flood, the stress on one side of the bridge is reduced by about 50%, and the stress on the other side is increased by about 6%. By analyzing the geometric nonlinearity of masonry bridge and the double nonlinearity of geometric material, it is found in this paper that the ultimate live load coefficient of masonry bridge under double nonlinearity is about one third of that in the case of geometric nonlinearity. The results under double nonlinearity should be closer to the actual situation and more accurate. It is found that the ultimate live load coefficient of the masonry bridge is about 4% less than that of the middle load when the bridge load is arranged laterally, which indicates that the structure of the masonry bridge is more unfavorable under the eccentric load. After different reinforcement, the structure of masonry bridge is obviously improved, the normal maximum displacement is reduced by about 20%, and the ultimate maximum displacement is reduced by about 30%. Among the different reinforcement methods, the ribbed reinforcement method can not only save materials but also reinforce effectively, so it is the most ideal reinforcement method. In the aspect of dynamic analysis of masonry bridges, the seismic responses of masonry bridges before and after strengthening are analyzed under different seismic waves. It is found that under different earthquake conditions, masonry bridges before and after strengthening are relatively stable in the direction of the transverse bridge, and the displacement changes are only about 8%, while the displacement along the bridge and the vertical direction range from 10% to 30%, indicating that in the design of seismic reinforcement, It is necessary to strengthen the seismic design along the bridge direction and vertical direction; the stress decreases little under all earthquakes, and is about 13%, which shows that the reinforcement can make the masonry bridge resist the occurrence of earthquake stress very well. Can play a very good seismic action in the earthquake process.
【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.72
本文编号：2285529
[Abstract]:Masonry bridges are very common in China. Before 1970s, most of them were masonry bridges. Now with the continuous development of economy, the continuous increase of bridge operation load, the unceasing influence of natural environment, the destruction of natural disasters such as earthquake, the existing masonry bridges are generally lack of bearing capacity and so on. Even some masonry bridges are too damaged to collapse. Therefore, it is of great significance to study the bearing capacity and seismic resistance of masonry bridges. The study of strengthening and optimization of masonry bridges can provide valuable reference for the strengthening design of damaged bridges. In the aspect of static analysis of masonry bridge, the influence of defects, flood impact and ultimate bearing capacity of masonry bridge are studied in detail in this paper. It is found that when the defects of the masonry bridge are located inside the arch foot, they have the greatest influence on the structure, and the stress concentration appears in the defects, and the stress increases by about 40%. Therefore, it is necessary to avoid the occurrence of such defects. In design, the arch can be designed as a variable cross section with thin intermediate ends. Under the action of flood, the stress on one side of the bridge is reduced by about 50%, and the stress on the other side is increased by about 6%. By analyzing the geometric nonlinearity of masonry bridge and the double nonlinearity of geometric material, it is found in this paper that the ultimate live load coefficient of masonry bridge under double nonlinearity is about one third of that in the case of geometric nonlinearity. The results under double nonlinearity should be closer to the actual situation and more accurate. It is found that the ultimate live load coefficient of the masonry bridge is about 4% less than that of the middle load when the bridge load is arranged laterally, which indicates that the structure of the masonry bridge is more unfavorable under the eccentric load. After different reinforcement, the structure of masonry bridge is obviously improved, the normal maximum displacement is reduced by about 20%, and the ultimate maximum displacement is reduced by about 30%. Among the different reinforcement methods, the ribbed reinforcement method can not only save materials but also reinforce effectively, so it is the most ideal reinforcement method. In the aspect of dynamic analysis of masonry bridges, the seismic responses of masonry bridges before and after strengthening are analyzed under different seismic waves. It is found that under different earthquake conditions, masonry bridges before and after strengthening are relatively stable in the direction of the transverse bridge, and the displacement changes are only about 8%, while the displacement along the bridge and the vertical direction range from 10% to 30%, indicating that in the design of seismic reinforcement, It is necessary to strengthen the seismic design along the bridge direction and vertical direction; the stress decreases little under all earthquakes, and is about 13%, which shows that the reinforcement can make the masonry bridge resist the occurrence of earthquake stress very well. Can play a very good seismic action in the earthquake process.
【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.72
【相似文献】
相关期刊论文 前6条
1 雪彦鹏;;预应力框架技术在加固圬工桥台侧墙上的应用[J];重庆建筑;2011年07期
2 方立人;;预应力锚索在圬工桥台加固中的应用[J];山西建筑;2012年17期
3 ;大打设备翻身仗,发展养桥机械化[J];铁道建筑;1976年02期
4 方建华;;预应力锚索技术在圬工桥台的加固应用[J];公路交通科技(应用技术版);2008年08期
5 徐兮;;圬工桥拱轴线变形观测及其分析研究[J];城市勘测;2009年01期
6 ;[J];;年期
相关会议论文 前1条
1 孙金才;;简析桥梁弧形支座上摆锚栓折断的原因[A];2006北京铁路局技师论文集[C];2006年
相关硕士学位论文 前1条
1 朱海;圬工桥加固优化及稳定性研究[D];中国石油大学(华东);2015年
，本文编号：2285529
本文链接：https://www.wllwen.com/kejilunwen/daoluqiaoliang/2285529.html
