华南风化土崩岗的孕育形成本因与灾变破坏机理研究

崩岗属一种地质侵蚀灾害，被学术界称为"生态溃疡"。项目针对华南地区崩岗灾害频发、其机理认知不清、治理存在"治标不治本、久治不愈"的现状为背景，通过土质学、土力学与灾害地质学结合的研究方法，采用"宏观地质+中观土性+微观演化+气候影响→机理→应用"的研究思路，以风化土的裂隙性、遇水软化、易崩解性为出发点，结合炎热多雨气候影响，设计湿化试验与浸水崩解试验，从地质构造、气候影响等宏观尺度研究崩岗的孕育环境与驱动因素；从风化土的物化组成、岩土特性等中观尺度研究崩岗的物源性质与控制影响，从裂隙、孔隙分布等微观尺度研究崩岗灾害破坏的结构演化反映，从本质上揭示崩岗的孕育形成本因与灾变破坏机理，评价崩岗灾变过程中土体抗剪强度减损规律，探寻崩岗形成与发展的主控因素与致灾因子，进行跨尺度下各因子的敏感性与关联性分析，提出基于岩土本性分析的崩岗灾害评价方法，为崩岗灾害的预测预报、控制对策及综合治理提供科学依据。

Slump gully, one of the geological erosion disasters, is referred to as an ecological ulcer. Considering that the slump gully frequently occurs, and only the symptoms are treated without tracking the disaster mechanism that treatment is intractable at present. This program will be carried out by the combining methods of soil science, soil mechanics and disaster geology and ideas of "macro-disaster + meso-formation + micro-gestation → mechanism → application" in the following. Firstly, research on the formative environment and driving factors such as geologic structure and climate impacts of slump gully from the macro-scale will be performed. Secondly, source properties and main controlling factors such as the physicochemical composition and characteristics of weathered soils from meso-scale will be studied. Taking into account the special characteristics of fissure, softening and disintegration when encountering water, this program plans to conduct slaking tests and disintegration tests. Thirdly, the evolution and failure of soil structure related to the distribution of fissures and pores from micro-scale. Consequently, the incubation cause of the slump gully and its damage mechanism will be revealed essentially, the rule of shearing strength reduction during the process of the disaster will be evaluated, and the controlling and impact factors of its formation and development will be explored. Furthermore, the sensitivity and correlation analyses of each factor are built in trans-dimension, and a hazard evaluation method is proposed based on the soil properties of slump gully, which provides scientific basis for the forecast, controlling measures and comprehensive treatment of the slump gully disaster.