大跨连续刚构桥双肢薄壁高墩模型试验研究

发布时间：2018-04-11 15:53

本文选题：大跨连续刚构桥 + 双肢薄壁高墩　；参考：《中南林业科技大学》2017年硕士论文

【摘要】：西部地区,由于受到地形条件的限制,公路桥梁须跨越陡峭的峡谷,双肢薄壁高墩大跨连续刚构桥是深沟等复杂地形条件下的理想桥型。目前,国内外学者对大跨连续刚构桥开展了大量的研究,研究成果相对成熟,但对大跨连续刚构桥双肢薄壁高墩的拟静力性能和抗推极限承载力的研究相对较少。本文以张家界太极溪特大桥主桥施工监控为工程背景,以12#墩为研究对象,设计制作1:16的缩尺模型,对双肢薄壁高墩的拟静力性能和抗推极限承载力进行试验研究。其主要内容如下:(1)以结构模型试验基本理论为基础,根据量纲分析法推导出集中荷载作用下,模型与原型相似的应力、应变、位移相似关系。以张家界太极溪特大桥主桥12#墩为研究对象制作试验模型。并根据试验目的设计试验加载方案、试验荷载工况,以及测试断面、测点布置和测试方案。(2)利用有限元分析软件MIDAS/CIVIL2016对实桥进行有限元分析,得出实桥墩在不同工况作用下墩底截面、墩横系梁截面的应变理论值,墩顶截面的位移理论值,所得到的应变理论值和位移理论值与施工监控的实测值作对比,得知墩底截面和墩横系梁截面的应变监控实测值以及墩顶截面的位移监控实测值均小于理论计算值,且监控实测值与计算值变化趋势基本一致。(3)根据实桥悬臂施工过程的实际受力工况设计模型墩的试验加载工况,对模型墩进行低周反复荷载试验,并在试验过程中观测试件的裂缝开展情况及整个破坏模式。将有限元模型计算得到的理论数据与试验数据以及试验墩试验数据与原桥墩监测数据进行对比。并且从破坏特征、滞回曲线、耗能性能、骨架曲线和刚度退化特性方面进行分析,得知双肢薄壁高墩的受力性能和破坏机理。(4)利用有限元软件ANSYS建立空间有限元模型求解模型墩抗推极限承载力,并通过模型试验对比分析,得知试验墩抗推极限承载力的试验值与计算值基本相一致,且误差相对较小。将试验墩计算结果与试验结果进行相似比还原,再与原桥桥墩计算结果进行比较,发现其吻合度相对较高。(5)最后,综合试验数据和理论计算数据得出了结论,提出有待研究的问题。
[Abstract]:In western China, due to the limitation of terrain conditions, highway bridges have to cross steep canyons. Two-legged thin-walled high-pier long-span continuous rigid frame bridge is an ideal bridge type under complicated terrain such as deep ditches.At present, scholars at home and abroad have carried out a lot of research on long-span continuous rigid frame bridge, and the research results are relatively mature, but the research on quasi-static behavior and ultimate bearing capacity of two-leg thin-walled high-pier of long-span continuous rigid frame bridge is relatively few.In this paper, taking the construction monitoring and control of the main bridge of Taijixi Bridge in Zhangjiajie as the engineering background, taking the 12# pier as the research object, the 1:16 scale model is designed and made, and the quasi-static behavior and the ultimate bearing capacity of the double-leg thin-walled high pier are tested and studied.The main contents are as follows: (1) based on the basic theory of structural model test, the similarity of stress, strain and displacement between the model and the prototype under concentrated load is derived according to the dimensional analysis method.Taking the 12# pier of Taijixi Bridge in Zhangjiajie as the research object, the test model is made.According to the purpose of the test, the test loading scheme, test load condition, test section, measuring point arrangement and test plan are designed. The finite element analysis software MIDAS/CIVIL2016 is used to analyze the real bridge.Under different working conditions, the strain theory value of piers bottom section, the cross beam section of pier, the displacement theory value of pier top section, the theoretical strain theory value and displacement theory value are compared with the measured value of construction monitoring.The results show that the measured values of the bottom section of the pier and the cross section of the piers and the displacement monitoring of the section of the pier top are all smaller than the calculated values of the theoretical calculation.According to the actual load condition of the cantilever design model pier, the model pier is tested under low cycle repeated load, according to the experimental loading condition of the model pier, and the monitoring measured value is basically consistent with the change trend of the calculated value.The crack development and the whole failure mode of the specimen were observed during the test.The theoretical and experimental data obtained by finite element model calculation and the test data of test pier are compared with the monitoring data of the original bridge pier.The damage characteristics, hysteretic curves, energy dissipation properties, skeleton curves and stiffness degradation characteristics are analyzed.It is known that the mechanical behavior and failure mechanism of two-leg thin-walled high pier. (4) the finite element software ANSYS is used to establish the spatial finite element model to solve the ultimate bearing capacity of the model pier, and through the model test, the ultimate bearing capacity of the model pier is compared and analyzed.It is known that the test value of the ultimate bearing capacity of the test pier is basically consistent with the calculated value, and the error is relatively small.Comparing the calculated results of the test piers with those of the original bridge piers, it is found that the degree of coincidence is relatively high. Finally, the conclusion is obtained by synthesizing the experimental data and the theoretical calculation data.The problems to be studied are put forward.
【学位授予单位】：中南林业科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U448.23

【相似文献】