堆石混凝土宏细观非局部化模型的开发

The technology of rock filled concrete was invented by our research team, which owns the independent intellectual property for this invention. The rock filled concrete is an innovative construction material in hydraulic engineering and civil engineering, which has advantages including low consumption of cement, low cost, compatible with industrial wastes, and this technology has been applied on more than 30 hydraulic construction projects. Therefore, economical and environmental benefits can be achieved with this technology. In order to promote the application of rock filled concrete in some higher dams with the height of more than 100m and evaluate the safety for the existing rock filled concrete dam， it is essential to investigate the fracture mechanism of rock filled concrete in meso-view. This research will investigate the fracture process of rock filled concrete under loading. The fractural meso-mechanics and random aggregate modeling method will be employed to develop a non-localized model for rock filled concrete and related numerical solutions. Then the damage and fracture propagation of rock filled concrete will be investigated. The CT scanning, digital speckle technologies, inspection method of energy from interface separation, and three point bending beam test will be employed to provide the input parameters and validate the proposed model. In the end, the proposed model will be utilized to evaluate the safety and reliability on multiple dams built with rock filled concrete in China. The proposed research can be the theoretical foundation and a reference for the laboratory tests when building some rock filled concrete dam with the height of more than 100m.

堆石混凝土技术由申请人团队发明，具有自主知识产权，并成为一种新型水工与土木建筑材料。其具有水泥用量少，造价低和可容纳多种固体废物等多种经济、节能环保优势，已应用于30 多个水利工程项目。为推广堆石混凝土材料在百米级大坝的应用、评价已建大坝的安全性，需要研究堆石混凝土细观断裂机理。本项目以堆石混凝土材料在载荷作用下破坏过程为研究对象，以建立堆石混凝土的非局部化模型为重点，以分析和研究堆石混凝土材料在工程中的断裂损伤发展情况为目标，交叉应用了脆性细观力学方法、随机骨料建模方法来建立堆石混凝土宏细观损伤非局部化本构模型及相关的数值求解格式。结合CT扫描技术、数字散斑技术、界面分离能测试方法和三点弯曲梁试验，获得模型参数及验证模型有效性。进一步采用本项目提出的本构模型来对于国内已建的多座堆石混凝土大坝进行安全性与可靠性评估。该项目的研究可以为建造百米级的堆石混凝土大坝提供可靠的实验依据及理论基础。

本项目以在载荷作用下堆石混凝土材料的多尺度破坏过程为分析为目标。通过采用试验力学方法，计算力学方法，夹杂理论解析方法分别；并结合CT扫描技术、数字散斑技术、界面分离能测试方法和三点弯曲梁试验和四点弯曲梁试验开展对于堆石混凝土材料的细观破坏行为，宏细观力学参量的关系，堆石混凝土材料的随机骨料建模，堆石混凝土性能解析预测理论和混凝土材料的破坏特征表征等方面的研究。而主要的研究工作内容可以归纳为以下三个主要方面,即：1.堆石混凝土材料的多尺度力学行为解析预测方法；2.堆石混凝土材料的数值仿真技术；3.堆石混凝土材料的宏观性能预测分析方法。本项目的成果将会为推广堆石混凝土材料在百米级大坝的应用、评价已建大坝的安全性，奠定理论；且通过本项目的研究也从细观尺度上了解了堆石混凝土断裂机理,以及裂纹扩展的规律。同时通过本项目的研究成果对于国内已建的多座堆石混凝土大坝进行安全性与可靠性评估，并与相关的现场观测数据具有高度的相似性。可以说本项目的研究成果已经为建造百米级的堆石混凝土大坝可靠性和安全性评估提供坚实的理论基础。