基于实测预应力值的既有混凝土构件性能推定方法
A Performance Estimation Method for Exsiting Concrete Components Based on Measured Prestress Values
许庆 1李嘉伟 2曾滨 2徐晓达 2张灏达2
作者信息
- 1. 中冶建筑研究总院有限公司,北京 100088;清华大学土木工程系,北京 100084
- 2. 中冶建筑研究总院有限公司,北京 100088
- 折叠
摘要
为了提出既有预应力混凝土构件考虑有效预应力分布的性能评定方法,揭示有效预应力抽样检测值与预应力混凝土结构性能分析特征参数的映射关系,验证预应力混凝土结构有效预应力基于高斯混合统一概率模型的总体分布规律.在实测有效预应力值样本数据的基础上,基于统一概率模型采用特征加权法和最大期望算法(EM)等概率统计方法,提取有效预应力分布典型特征,并引入95％保证率条件下的承载力特征值对结构服役性能进行定量计算,提出了一种基于实测样本数据的既有预应力混凝土构件性能推定方法.以某无黏结预应力混凝土结构为工程实例,使用设计复核法与特征值法分别评价结构服役性能.研究表明,与现行评价方法相比,特征值法能较好地拟合实际情况,且能够有效地保证结构的安全性和可靠性,可为既有预应力混凝土结构的性能评价和加固设计提供参考依据.
Abstract
In order to put forward a performance evaluation method for existing prestressed concrete mem-bers considering the distribution of effective prestress,reveal the mapping relationship between the sampling test values of effective prestress and the characteristic parameters of the performance analysis of prestressed concrete structures,and verify the overall distribution law of effective prestress of prestressed concrete structures based on Gaussian mixture unified probability model,based on the sample data of the measured effective prestress values,the typical characteristics of the effective prestress distribution are extracted by the probabilistic and statistical methods such as feature weighting method and maximum expectation algo-rithm(EM)based on the unified probability model,and the characteristic value of the bearing capacity un-der the condition of 95％guarantee rate was introduced for quantitative calculation of the service perform-ance of the structure.A method for predicting the performance of existing prestressed concrete members based on measured sample data was proposed.Taking an unbonded prestressed concrete structure as an en-gineering example,design review method and eigenvalue method were used to evaluate the service perform-ance of the structure respectively.The results showed that compared with the existing evaluation methods,the eigenvalue method could better fit the actual situation and effectively ensure the safety and reliability of the structure,so as to provide a reference for the performance evaluation and reinforcement design of the ex-isting prestressed concrete structures.
关键词
预应力混凝土结构/有效预应力/统一概率模型/实测样本数据/评价特征值Key words
prestressed concrete structure/effective prestress/unified probability model/measured sample data/evaluation of characteristic values引用本文复制引用
基金项目
十四五重点研发计划(2022YFC3801800)
国家自然科学基金项目(52378320)
国家自然科学基金项目(52308334)
出版年
2024
NETL
NSTL
万方数据