高拱坝混凝土循环应力-温-湿耦合模型与长期性能提升方法研究

针对西南地区长期自然风化作用协同坝体复杂应力状态的真实服役环境，开展荷载与环境因素长期耦合作用下长江流域高拱坝混凝土综合性能演变规律试验研究，建立长期耦合作用下混凝土性能时变衰减模型，揭示不同耦合参数与高拱坝混凝土性能的相互关系；进而开展长期服役环境下水泥水化产物和混凝土微细结构演变规律研究，建立混凝土微细观结构损伤与宏观性能演变之间的数值模型，揭示长期服役环境下高拱坝混凝土劣化机理；结合试验和工程实测数据，构建基于性能衰减的高拱坝混凝土长期性能综合评价动态指标体系，提出高拱坝混凝土性能评价时变模型和服役年限预测方法；开展高拱坝混凝土阻裂增韧理论与方法研究，揭示荷载与环境因素长期耦合作用下高拱坝混凝土开裂机理，建立基于功能团设计的高性能、性能调节型的新型高拱坝混凝土设计理论，研发长寿命、绿色高拱坝混凝土及其制备工艺，为提升高拱坝混凝土耐久性提供理论与方法。

Aiming at the actual service condition of the dam body in southwest district of China under the synergistic effect of long-term natural weathering and the complex stress, the experimental study in the evolvement rule of the comprehensive properties of high arch dam concrete in Yangtze River Basin under the long-term coupling effect of load and environment factors will be conducted. The time-varying attenuation model of concrete properties under long-term coupling effect will be established to reveal the mutual relation between different coupling parameters and properties of high arch dam concrete. And then, the evolvement rule of micro and meso structures of cement hydration products and concretes under long-term service condition will be studied. The numerical model between the micro and meso structural damage and the macroscopic performance evolvement of the concrete will be established to reveal the deterioration mechanism of high arch dam concrete under long-term service condition. Combined with experiments and measured data in practical engineering projects, the dynamic index system for comprehensive evaluation based on performance degradation of long-term properties of high arch dam concrete will be established to present the time-varying model for performance evaluation and predicting method for service life of high arch dam concrete. Besides, the theory and methodology of the crack resistance and toughening for high arch dam concrete will be studied to reveal the crack mechanism of high arch dam concrete under the long-term coupling effect of load and environment factors. The design theory based on functional groups of new high arch dam concrete with high performance and adjustable properties will be put forward to research and develop green concretes as well as the preparation technique with long service life used in high arch dams, which can provide theory and methods to improve durability of high arch dam concrete.