特高坝与近坝山体异常变形驱动机制及安全防控理论和方法

A giant open system (called super-high dam-mountain system) is formed by super-high dam and high steep mountain on both sides. The super high dam, reservoir side mountain, large capacity and harsh working environment together have brought great challenges to the safety of engineering. The deformation behaviors of both sides of the mountain and the super-high dam are the most intuitive characterization in the safety operation system, which are affected by many factors including environments, materials, and strong interactions between the dam and mountain. In order to reveal the drive mechanism of super high dam-mountain abnormal deformation system, and develop the safety control theory, a thoroughly analysis of the mutual feeding behavior of super-high dam and mountain under multiple factors is conducted with the aid of multi-disciplinary research and the integrated use of multiple instruments. On the basis of this, the drive mechanism of abnormal deformation and instability of the super-high dam-mountain system is clarified. In addition, the monitoring, prediction and diagnosis model, criteria and methods of the super-high dam-mountain deformation system are explored to improve the multidimensional scale deformation safety monitoring theory of the super-high dam-mountain system. Moreover, the deformation abnormality criterion, early warning criteria and indicators of the whole life cycle and risk control model and decision making method of the super-high dam-mountain system are proposed to form a perfect multistage warning and risk prevention and control system of the super-high dam-mountain abnormal deformation system.

特高坝与两岸高陡山体构成一个巨型开放系统(称特高坝-山体系统)，由于超高的坝高与库岸山体、超大的库容、恶劣的服役环境，给工程的安全保障带来了极大的挑战和诸多的难题。特高坝与两岸山体的变形性态作为整个系统运行安全的最直观表征，受材料、环境等多因素、大坝与近坝山体强相互作用的综合影响。本项目从深入揭示特高坝-山体系统异常变形驱动机制、发展和完善其安全控制理论与方法的目标出发，拟借助多学科的交叉融合和多手段的综合应用，开展多因素作用下特高坝与近坝山体互馈力学行为的深入剖析，以明晰特高坝-山体系统变形异常和失稳的驱动机制；开展特高坝-山体系统变形性态监测、预报、诊断等模型、标准、方法的系统探研，以构建特高坝-山体系统变形安全多维多尺度监控理论；开展特高坝-山体系统变形转异判据、预警准则与指标以及全寿命周期风险调控模型和决策方法的深入研究，以形成特高坝-山体系统异常变形多级预警和风险防控体系。

我国相继建设和规划了一批特高坝工程，但工程地质地形条件和运行工况大多异常恶劣和复杂，较多技术指标突破了现行规范和标准，给工程长期安全运行带来了极大挑战，为此，项目组深入开展了特高坝-山体系统异常变形演化机理与安全控制理论和方法的创新性研究。首先，剖析了岩体开挖卸荷、坝体填筑、阶梯蓄水对坝体和山体变形的影响机制，挖掘了变形的时变规律以及结构稳定性和极限承载能力的演化规律，揭示了结构异常变形和系统失稳模式的驱动机制；提出了互馈面、互馈作用区的典型局域模拟模型的建模方法，提出了劣势互馈面的判定方法及其转异诊断方法。其次，提出了特高坝-山体系统整体与局部变形监测新方法，研究了变形性态的全景动态可视化建模方法，建立了跟踪监控模型以及变形参数反演模型，搭建了工作性态综合诊断指标体系、评判准则等知识工程。再次，建立了特高坝-山体系统变形确定性监控模型和混合监控模型，提出了变形变异特性的诊断模型和诊断标准；挖掘了特高坝变形性态变异机理，提出了变形性态变异的预警指标拟定方法和指标体系构建方法。最后，发展了工程补控措施精细化试验、数值模拟技术，研究了工程补强效能的确定性与不确定性组合评估方法和长期效力预测模型，建立了特高坝-山体系统组合风险率计算模型。依托本项目，出版著作5部，发表论文154篇，研究成果应用于小湾、锦屏一级、二滩、李家峡等多座高坝工程，获2020年水力发电科技进步一等奖 1项、2021年江苏省科技进步二等奖1项。本成果创建的特高坝及山体长期变形性态与服役安全保障技术，为工程安全提供了源头的理论依据和技术支撑，有力地推动了水利行业科技进步和水利工程学科发展，社会和经济效益重大，推广应用前景广阔。