| In mountain and ravine region of southwest China, there are lots of quaternary glacial deposits. With hydropower projects, traffic engineering and transmission project, et al built in mountain and ravine region, geo-hazards and engineering geological problems are becoming more serious. So, it is theoretical significance and actual value to study geo-engineering properties and disaster effects of quaternary glacial deposits, to analysis stability of glacial deposit slope and offer some reasonable and effective slope protection measures.Based on the achievements of past generations as well as our own and the detailed geology investigation, the paper studied the quaternary glaciations, the composition and distributions of glacial deposits of Baimang Mountains, Yulong Mountains and Gongga Mountains. Technical method on the combination of digital image processing with laboratory test is introduced in the paper. Based on fractal and fractal dimension theory, the granularity characters, the directional dimension of rock blocks and the configuration characters are analyzed.In order to gain basic geo-engineering properties of glacial deposits in study area, field direct shear tests and percolation tests were carried out. The results showed that the internal friction angle has wide ranges from 26.56°to 51.3°and the cohesion is lower than 5kpa generally. The permeability coefficient varies from 2×10-4cm/s to 6×10-4cm/s, and the permeability of glacial deposits is the same to fine sand's and silt sand's. The paper explored deformation, strength and permeability, and analyzed emphatically the relation between composition, fabric and engineering properties of the glacial deposit. The study laid a good foundation for analysis of slope stability.The field investigations indicated that the main failure modes of glacial deposits slopes are landslide, collapse and debris flow. The factors, which effect slope stability, are engineering properties of glacial deposits, rainfall, water erosion and slope excavation. Elastic-plastic slope models were built based on three typical glacial deposits slopes. By use of the software-FLAC3d, deformation character and stability of the slope under natural condition, earthquake actions and excavation at foot, was simulated. The study provides the basis for slope protection.The paper provided rational prevention suggestions to prevent various disasters according to the main factors effecting slope stability. The techniques and methodology used in this study can be referenced when studying the similar engineering geological subjects in other regions.
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