基于时变损伤的混凝土坝服役性能多尺度退化特性与协同诊断方法研究

With regard to performance degradation of in-service concrete dams under environment and load characteristics, previous studies indicate that multiple-factor synergy drive is a main cause for the dam performance degradation which is the main basis for judging dam safety state. Few attempts have been made to study performance degradation and comprehensive diagnosis of in-service concrete dams. This project aims to study the influence of environmental erosion on the deterioration of material properties of concrete dams, construct macroscopic mechanical model of concrete considering multiple injuries effect, investigate the interrelationship between dam performance evolution and the dependent factors by employing a strategy combining theoretical analysis, numerical simulation, test methods and in-situ observation. Furthermore, to reveal the mechanical performance evolution regulation of concrete dams under the complex factors, a structural performance evolution model under the coupled action of internal and external environment of concrete dams will be established, and a method for determining key parameters will be proposed by analyzing the coupling mechanism of two fields of the dam. The main disease indices of dam structure s will be reasonably chosen. The mapping relationship between dam multilayer index and the evaluation threshold, collaborative empowerment and cloud integration technology will be investigated. The concrete dam operation characters collaborative diagnosis method which fuses multi-source information of time and space will be proposed. The research outcomes produced by this project will lay the groundwork for concrete dam long-term service and provide technical support and scientific basis for management decisions.

针对环境与荷载作用下混凝土坝服役性能时变衰退特性，前期研究表明，多因素协同驱动是大坝性能退化的重要原因，坝体性能劣化程度又是评判大坝安全性态的主要依据，目前有关混凝土坝服役性能退化与综合诊断的系统研究相对较少。本项目拟采用理论分析、数值仿真、模型试验与原位观测相结合的研究方法，研究环境侵蚀对大坝混凝土材料性能劣化的驱动力与作用效应，构建多重损伤联合效应下混凝土宏观力学性能仿真分析模型，揭示坝体性能演化与其依存诸因素间的内在关联；更进一步，通过对坝体两场耦合作用机理分析，建立混凝土坝内外环境耦合作用的结构性能演化模型和关键参数的确定方法，以期揭示复合因素作用下混凝土坝性能力学演变规律；合理拣选大坝结构主要病害指标，探究大坝多层指标与评价阀值的映射关系、协同赋权与梯阶云集成技术，研究并提出融合多源时空信息的混凝土坝运行性状协同诊断方法，从而为混凝土坝长效服役和管理决策提供技术支持和科学依据。

多因素协同驱动是混凝土坝服役性能时变衰退的重要原因，申请人前期研究表明，坝体性能劣化程度是评判大坝安全性态的主要依据，目前有关混凝土坝服役性能退化与综合诊断的系统研究相对较少。申请人拟采用理论分析、数值仿真、模型试验与原位观测相结合的研究方法，研究环境侵蚀对大坝混凝土材料性能劣化的驱动力与作用效应，构建多重损伤联合效应下混凝土宏观力学性能仿真分析模型，揭示坝体性能演化与其依存诸因素间的内在关联；更进一步，通过对坝体两场耦合作用机理分析，建立混凝土坝内外环境耦合作用的结构性能演化模型和关键参数的确定方法，以期揭示复合因素作用下混凝土坝性能力学演变规律；合理拣选大坝结构主要病害指标，探究大坝多层指标与评价阀值的映射关系、协同赋权与梯阶云集成技术，研究并提出融合多源时空信息的混凝土坝运行性状协同诊断方法，从而为混凝土坝长效服役和管理决策提供技术支持和科学依据。