钢筋混凝土桥墩水平撞击的模型试验与数值研究

发布时间：2018-01-14 23:25

本文关键词：钢筋混凝土桥墩水平撞击的模型试验与数值研究　出处：《华南理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着我国交通运输事业的不断发展，钢筋混凝土桥墩遭受水平撞击荷载的概率也越来越大。本文以桥墩水平撞击理论和有限元法为基础，利用模型试验和有限元数值计算技术，对钢筋混凝土桥墩的水平低速撞击问题进行了模型试验与数值研究。（1）概述了桥墩撞击的理论、试验及数值研究现状，总结归纳了当前国内外钢筋混凝土桥墩水平撞击问题的研究成果，提出了有待进一步研究的问题。（2）进行了圆截面钢筋混凝土桥墩的水平撞击模型试验，得到了两种工况下的位移时程曲线和钢筋、混凝土应变时程曲线，分析了桥墩整体的变形情况，揭示了撞击过程中的振荡效应。（3）建立了基于两种常用混凝土动力本构模型的有限元模型，将计算结果与试验结果进行对比，，检验了本文所采用混凝土本构模型的适用性。分析表明在桥墩水平撞击时宜选用修正的弹塑性损伤帽盖混凝土模型进行数值计算。（4）分析有限元模型的计算结果，揭示了钢筋混凝土桥墩的主要的耗能机制。提出了一种基于竖向剩余承载力的损伤评估准则，具有较好的实用性和可操作性。（5）研究表明桥墩在遭受水平撞击时其截面抗弯强度受动力作用影响较大。本文基于参数分析的结果，使用回归拟合的数学方法提出了考虑水平撞击动力影响的钢筋混凝土桥墩截面动力抗弯强度实用计算公式。将简化实用公式结果与有限元结果进行对比，表明实用计算公式具有良好的计算精度。
[Abstract]:With the continuous development of transportation in China, the probability of reinforced concrete pier subjected to horizontal impact load is increasing. This paper is based on the theory of horizontal impact of pier and finite element method. The model test and numerical research on the horizontal and low speed impact of reinforced concrete pier are carried out by using model test and finite element method. This paper summarizes the theory, test and numerical research status of pier impact, summarizes the research results of horizontal impact of reinforced concrete pier at home and abroad, and puts forward some problems to be further studied. 2) the horizontal impact model test of reinforced concrete pier with circular section is carried out, and the displacement time history curve, steel bar and concrete strain time history curve under two working conditions are obtained, and the deformation of the pier as a whole is analyzed. The oscillatory effect during impact is revealed. A finite element model based on two kinds of concrete dynamic constitutive models is established, and the calculated results are compared with the experimental results. The applicability of the concrete constitutive model used in this paper is tested. The analysis shows that the modified elastoplastic damage cap concrete model should be used for numerical calculation in horizontal impact of bridge pier. (4) by analyzing the results of finite element model, the main energy dissipation mechanism of reinforced concrete pier is revealed, and a damage assessment criterion based on vertical residual bearing capacity is proposed. It has good practicability and maneuverability. The research shows that the flexural strength of the section of the pier is greatly affected by the dynamic action when it is subjected to horizontal impact. This paper is based on the results of parameter analysis. A practical formula for calculating the dynamic flexural strength of reinforced concrete pier section considering the influence of horizontal impact force is put forward by using the mathematical method of regression fitting. The simplified practical formula results are compared with the results of finite element method. It shows that the practical calculation formula has good calculation accuracy.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U443.22

【参考文献】