震损钢筋混凝土框架结构抗震性能评估方法研究

发布时间：2018-05-11 06:45

本文选题：震损结构 + 基于性能　；参考：《重庆大学》2014年博士论文

【摘要】：破坏性地震在我国时有发生，这些地震均造成大量房屋建筑的损伤与破坏；同时，早期建设的震损结构也存在着过早劣化的现象，面临着维修加固甚至提前退役的境遇，因此对地震受损钢筋混凝土结构进行抗震性能评估有着重要的现实意义。本文以框架结构为研究对象，从地震作用取值、损伤模型确定、抗震性能评估方法研究三个方面对震损结构抗震性能评估展开了深入的研究。论文的主要研究工作和成果如下： ①建立了均匀泊松分布地震发生概率模型和非齐次泊松分布地震发生概率模型，用于表征是否考虑场地历史地震发生信息；基于地震发生概率模型，给出了不同地震风险中的结构应选用的抗震评估设防准则。考虑结构不同使用寿命及结构后续服役期内场地地震具有不同超越概率的影响，推导出各抗震评估准则下结构评估烈度在剩余使用寿命内的超越概率换算为设计基准期为50年时的相当超越概率的计算公式；推导出各评估准则下水平地震影响系数最大值、地面峰值加速度与评估烈度之间的换算关系；给出了结构在不同评估准则、不同剩余使用寿命下的震损结构抗震性能评估用地震地震作用取值调整系数。 ②选取了47个钢筋混凝土压弯构件在低周往复加载损伤试验条件下获得的滞回曲线数据结果，根据Park-Ang损伤指数计算公式，计算出损伤构件不同损伤状态点对应的损伤指数值，，并通过数据回归分析，得到了损伤构件刚度退化系数和强度退化系数与构件损伤指数值之间的拟合关系式，建立了考虑地震损伤的损伤构件恢复力模型，并在此基础上提出了考虑材料劣化的震损构件恢复力模型；同时，在考虑材料劣化的损伤构件恢复力骨架线时，针对混凝土和钢筋材料劣化本构关系与混凝土碳化深度有着密切关系的现状，引入贝叶斯更新方法对已有混凝土碳化深度预测模型的预测结果进行了重新估计，使得预测结果的准确性和客观性得到大幅提高。 ③在既有结构基于性能的抗震评估方法研究中，静力弹塑性分析方法是一种重要的分析方法，本文基于模态弹塑性理论，结合动力时程分析方法和静力弹塑性分析方法的优点对传统Pushover分析方法中结构在地震作用下的顶点目标位移的确定方法以及考虑高阶振型影响的侧向力加载模式进行了改进，并详细给出了基于本文方法的建筑结构抗震性能评估流程。将改进方法应用于五层和十层完好框架结构以及十层地震受损钢筋混凝土框架结构的抗震性能评估中，计算结果表明：本文改进Pushover法能够有效模拟结构在地震作用下的真实反应，也能体现震损结构在后续地震作用过程中的非线性行为。 ④考虑到地震易损性分析是结构基于性能的抗震评估中一个必不可少的研究内容，且传统三水准地震作用并不能合理描述现行抗震设计规范中划分的五个结构性能目标，特别是不能为轻微地震损伤结构的抗震性能评估提供依据。为了完善了基于性能的既有钢筋混凝土结构抗震性能评估体系，作者针对既有结构可能遭遇的地震风险水平特征，参考已有研究成果，在现有小震、中震和大震地震作用水平基础上，新引入了一个50年地震超越概率为40%的地震作用水平，定义为“中小震”，并建立了既有钢筋混凝土结构在不同地震作用水平下的抗震性能水平目标。 ⑤建立了地震受损钢筋混凝土框架结构抗震性能评估方法的理论体系和基本流程，并以一栋10层钢筋混凝土框架结构为例，详细说明了震损结构抗震性能评估过程中损伤模型以及评估用地震作用取值的确定过程，并验算了结构不同损伤位置对各抗震性能评估方法可靠性和适用性的影响。
[Abstract]:Destructive earthquakes occur in our country. These earthquakes all cause damage and damage to a large number of building buildings. At the same time, the earthquake damage structure in early construction also exists premature deterioration, facing the situation of maintenance and reinforcement and even early retirement. Therefore, it is important to evaluate the seismic performance of the reinforced concrete structure of the earthquake damaged reinforced concrete. In this paper, the frame structure as the research object, from the seismic action value, damage model determination, seismic performance evaluation method three aspects of seismic performance evaluation of earthquake damage structure in-depth study.
(1) the probability model of homogeneous Poisson distribution and the probability model of non homogeneous Poisson distribution are established to characterize the historical seismic information of the site. Based on the probability model of earthquake occurrence, the seismic evaluation criteria for the structure of different seismic risk are given. The different service life of the structure is considered. As well as the effect of different transcendental probability on the site earthquake in the subsequent service period of the structure, this paper deduces the calculation formula of the transcendental probability conversion of the structural evaluation intensity within the remaining service life under the criteria of the remaining service life under the criteria of the seismic evaluation, and derives the maximum influence coefficient of the horizontal earthquake under the evaluation criteria, and the maximum value of the influence coefficient of the horizontal earthquake is derived. The conversion relation between the ground peak acceleration and the evaluation intensity is given, and the seismic performance evaluation of the earthquake damage structure under the different evaluation criteria and the remaining service life is given by the seismic seismic action adjustment coefficient.
The results of the hysteresis curve data obtained by 47 reinforced concrete compression members under the condition of low cyclic loading damage test are selected. According to the calculation formula of Park-Ang damage index, the damage index value corresponding to the damage state points of the damaged component is calculated. The stiffness degradation coefficient and the strength of the damaged component are obtained by the data regression analysis. The regression equation between the degree degradation coefficient and the damage index value of the component is set up, and the restoring force model of the damaged component considering the damage of the earthquake is established. On this basis, the restoring force model of the earthquake damage component considering the deterioration of the material is proposed. At the same time, the deterioration of the strength skeleton line of the damaged component considering the deterioration of the material is considered for the deterioration of the concrete and the steel material. The relationship between the constitutive relationship and the depth of concrete carbonization is closely related. The Bayesian updating method is introduced to reestimate the prediction results of the prediction model of the existing concrete carbonization depth, which makes the accuracy and objectivity of the prediction results greatly improved.
The static elastoplastic analysis method is an important analysis method in the study of the seismic performance based seismic evaluation method. Based on the modal elastoplastic theory, combined with the advantages of the dynamic time history analysis and the static elastoplastic analysis method, the displacement of the vertex target in the traditional Pushover analysis method under the earthquake action is made. The determination method and the lateral force loading mode considering the influence of high mode shape are improved, and the seismic performance evaluation process of the building structure based on this method is given in detail. The improved method is applied to the five and ten layer intact frame structures and the seismic performance evaluation of the ten layer seismic damaged reinforced concrete frame structure. The results show that the improved Pushover method can effectively simulate the real response of the structure under the earthquake action, and can also reflect the nonlinear behavior of the earthquake damage structure during the subsequent earthquake action.
It is considered that seismic vulnerability analysis is an essential research content in the performance-based seismic evaluation, and the traditional three level seismic action can not reasonably describe the five structural and performance targets divided in the current seismic design code, especially for the seismic performance evaluation of the slight earthquake damage structure. The seismic performance evaluation system of existing reinforced concrete structures is perfected. In view of the characteristics of the possible earthquake risk level that the existing structures may encounter, and referring to the existing research results, on the basis of the existing small earthquakes, medium earthquakes and large earthquake earthquakes, a new seismic action level of 40% of the 50 year earthquake surpassing probability is introduced. The seismic performance of existing reinforced concrete structures under different earthquake levels is established.
The theoretical system and basic flow of seismic performance evaluation method for earthquake damaged reinforced concrete frame structure are established. A 10 story reinforced concrete frame structure is taken as an example. The damage model in the seismic performance evaluation process of the earthquake damage structure and the determination of the value of earthquake action are described in detail, and the structure of different damage is checked. The influence of location on the reliability and applicability of various seismic performance evaluation methods.

【学位授予单位】：重庆大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TU375.4;TU352.11

【参考文献】