云南红土型水库库岸侵蚀失稳机理研究

This study is to research the erosion and instability of the laterite banks of reservoirs in Yunnan province where is suffering extreme arid climate. A research system will set up as laterite, water, erosion, instability and migration in which there are interactions among arid, rain and reservoir water on the banks. The study will be carried out by means of theoretical studies, model tests, micro and macro tests and IT technologies in which the micro and macro properties of laterite suffered erosion, lost stability and migration in reservoir banks will be explored and so the characteristic of erosion, instability and migration will be carried out. The core of the study is damage functions of water on the micro structure of laterite among the interaction of water and earth banks which based on the macro engineering properties of laterite of the earth banks and on model tests. By this research, the macro properties and correspond micro structure properties of laterite of banks in erosion, instability and migrations will be described in which the macro and micro properties will be integrated with the interactions of water and earth banks, the modes of erosion, instability and migration will be take out to describe the mechanism of erosion and instability of laterite banks. The key technologies and theoretical guides will be carried out by this research to prevent and cure the damages of laterite reservoirs in Yunnan province.

本项目针对云南红土型水库库岸侵蚀、失稳频繁发生并造成重大损失的现状，结合极端干旱气候，考虑干旱、降雨及库水作用，将"红土-水体-侵蚀-失稳-迁移"作为一个研究系统，采用理论研究、模型试验、宏微观试验以及先进计算技术相结合的研究方法，研究库岸红土在侵蚀、失稳、迁移过程中的宏微观特性以及对应的红土型库岸侵蚀、失稳、迁移特征，注重水-土间复杂的交互作用，以水对红土微结构的损伤为核心，以库岸红土的宏观工程特性为依据，以模型试验及实际工程观测研究结果为基础，将库岸红土在侵蚀、失稳、迁移过程中的宏微观特性与其侵蚀、失稳、迁移特征和水-土相互作用关系结合起来，阐明库岸红土在侵蚀、失稳过程中的宏观特性及其对应的微结构特性，阐明库岸红土的侵蚀、失稳、迁移过程及特征，提出侵蚀、失稳、迁移模式，阐明库岸红土的侵蚀、失稳机理。为有效防治云南红土型水库的病害提供关键技术和理论指导。

本项目针对云南红土型水库库岸侵蚀、失稳频繁发生并造成重大损失的现状，选择侵蚀、失稳典型的红土型库岸进行实地踏勘，观测、分析了实际红土型库岸的侵蚀、失稳现状、特征等。以现场调查获得的典型红土型库岸区域的地形、地质、气象及降雨资料为依据，通过自行研制的人工模拟降雨装置及红土型模型库岸，进行了干旱、降雨及库水作用下红土型库岸侵蚀、失稳的模型试验，明确了红土型库岸的侵蚀、失稳、物源迁移过程、特征及模式。进行了干旱、降雨及库水作用下库岸红土的宏微观试验，阐明了相应条件下库岸红土的宏微观特性及其变化规律。通过研究降雨及库水作用下坡度、坡长、红土理化特性及强度特性与坡面侵蚀模数的关系、坡面径流特性、坡面红土起动的临界条件、侵蚀过程中的水-土相互作用及红土微结构特性变化，阐明了降雨及库水作用下红土型库岸的侵蚀机理。通过研究干旱、降雨及库水作用下红土理化特性、强度特性、微结构特性的变化、测试的模型库岸内应力和孔隙水压力的变化、建立力学模型进行红土型库岸稳定性分析，阐明了降雨及库水作用下红土型库岸的失稳机理。项目的研究既丰富和充实了红土的研究内容，奠定深入研究红土的基础，又可为云南红土型库岸及其他红土型边坡的侵蚀、失稳及相关红土型地质灾害的防治提供参考。