变高度钢筋混凝土连续梁的损伤识别研究

发布时间：2018-07-22 10:15

【摘要】：本文以连续梁整体化刚度模型的建立为首要条件,利用支座反力二次差值构成评价指标,应用静力学和有限元理论,模拟连续梁损伤状态,建立三跨连续梁损伤定位识别的静力响应理论模型。利用所建立的理论模型计算结果,研究不同损伤状态下评价指标的变化量,根据评价指标的静力响应特性,对损伤识别定位的精度和敏感度提出要求。利用结构损伤前后的静力响应数据,研究评判指标与损伤结构之间的新型静力损伤识别定位方法,提高静力损伤识别定位方法的精确度。(1)简述结构有限元分析软件迈达斯,按钢筋混凝土连续梁为变高度情况,建立三跨连续梁的MIDAS有限元模型;根据结构力学力法,建立三跨连续梁的力法方程,为本文以后的损伤识别研究奠定理论基础。(2)为解决传统力学分析中所遇到的刚度不连续分布所带来的难题,运用静力学理论和傅里叶级数理论,基于钢筋混凝土连续梁为变高度情况,建立连续梁整体化刚度模型。该刚度模型能将钢筋混凝土连续梁结构随机出现的离散裂缝或缺陷用统一的整体化刚度模型表示,建立三跨连续梁的损伤力学模型:计算移动荷载作用下各关键控制截面处的支座反力值,并利用MIDAS软件进行模型准确度校核。(3)基于连续梁整体化刚度模型,研究损伤发生后钢筋混凝土连续梁的支座反力二次差值变化值,根据不同损伤状态下所得到的支座反力二次差值曲线对钢筋混凝土连续梁进行损伤定位、识别、承载力估算,完成损伤识别。
[Abstract]:In this paper, the integral stiffness model of continuous beam is taken as the primary condition, and the secondary difference of bearing reaction force is used to form the evaluation index. The damage state of continuous beam is simulated by using the theory of statics and finite element method. A static response model for damage location identification of three-span continuous beam is established. Based on the calculated results of the established theoretical model, the variation of evaluation indexes under different damage states is studied. According to the static response characteristics of the evaluation indexes, the accuracy and sensitivity of damage identification and location are required. Based on the static response data before and after structural damage, a new static damage identification and location method between the evaluation index and the damaged structure is studied in order to improve the accuracy of the static damage identification and location method. (1) the finite element analysis software Midas is briefly described. According to the variable height of reinforced concrete continuous beam, the Midas finite element model of three span continuous beam is established, and the force method equation of three span continuous beam is established according to the structural mechanics force method. (2) in order to solve the problem caused by the discontinuous distribution of stiffness in the traditional mechanical analysis, the static theory and Fourier series theory are used to solve the problem. Based on the variable height of reinforced concrete continuous beam, the integral stiffness model of continuous beam is established. The stiffness model can express the discrete cracks or defects in reinforced concrete continuous beam structure by the unified integral stiffness model. The damage mechanics model of three-span continuous beam is established. The reaction force of each key control section under moving load is calculated, and the model accuracy is checked by Midas software. (3) based on the integral stiffness model of continuous beam, This paper studies the secondary difference value of support reaction force of reinforced concrete continuous beam after damage occurs. According to the quadratic difference curve of support reaction force obtained under different damage state, the damage location, identification and bearing capacity estimation of reinforced concrete continuous beam are carried out. Complete damage identification.
【学位授予单位】：吉林建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U446

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