基于结构单元堆积理论的黄土湿陷性预测模型研究

The assessment of loess for collapsibility is one of the fundamental key problems in theoretical research and engineering application which is indispensable and need to break through immediately.In order to develop various conceptual microstructure models for characterizing the collapsible loess deformation, this project regards the type, material composition and properties particles and aggregates at multi-scale as a breakthrough point, aiming to identify the function of basic structure units in collapsible deformation under different conditions. In order to investigate the basic dynamical mechanism of packing behavior that triggers the collapsible deformation, this program target revealing the mechanism properties and strength of bonds between multi-scale particles and aggregates. Based on the work above, a large number of compression collapse tests will be conducted to verify the application accuracy of each existing packing theory model on characterize loess collapsible deformation. With numerical analysis and field soaking tests, the theory model will be rectified and optimize, the prediction model for characterizing loess collapsibility based on structural unit packing theory will also be developed. The project will introduce packing theory into loess collapsibility forecast evaluation and explore a new method to quantify collapse deformation based on mechanism of loess collapsible deformation, which plays a significant role in both theoretical research of loess collapsibility and engineering application on collapsible loess site.

黄土湿陷性评价是湿陷性黄土理论研究和工程应用中不可或缺又亟待突破的关键基础问题之一。项目拟以不同尺度颗粒和团聚体的类型、物质组成及性质的深入研究为突破口，将目标锁定在辨识各种工况下对湿陷变形发挥功能的基本结构单元，建立清晰的黄土湿陷变形基本结构单元概念模型；对触发黄土湿陷变形堆积行为的基本动力学机制进行研究，将目标锁定在揭示不同尺度颗粒间和团聚体间连接的性质和强度，探索触发黄土湿陷变形堆积行为的基本动力学机制。在此基础上通过大量湿陷压缩试验对现有堆积理论模型在表征黄土湿陷变形方面的准确性进行逐一验证，对比优选出适于定量表征黄土湿陷变形的堆积模型。借助数值分析等方法结合场地浸水试验对模型进行矫正和优化，建立基于结构单元堆积理论的黄土湿陷性预测模型。项目将堆积理论引入黄土湿陷性预测评价，探索基于湿陷变形机理对湿陷变形进行定量表征的新途径，对黄土湿陷性理论研究和湿陷性黄土工程应用均具有重要意义。

黄土湿陷性评价是湿陷性黄土理论研究和工程应用中不可或缺又亟待突破的关键基础问题之一。本项目以不同尺度颗粒和团聚体的类型、物质组成及性质的深入研究为突破口，将目标锁定在辨识各种工况下对湿陷变形发挥功能的基本结构单元，建立了清晰的黄土湿陷变形基本结构单元概念模型；对触发黄土湿陷变形堆积行为的基本动力学机制进行研究，将目标锁定在揭示不同尺度颗粒间和团聚体间连接的性质和强度，探索了触发黄土湿陷变形堆积行为的基本动力学机制。在此基础上探索了基于结构单元堆积理论在黄土湿陷性预测中的适用条件，并通过大量湿陷压缩试验以及结合场地浸水试验通过数值法等方法分析探讨了黄土湿陷预测模型，项目成果对黄土湿陷性理论研究和湿陷性黄土工程应用均具有重要意义。