| Red beds are typical of layered rock, the geological nature of the project clearly anisotropic. Compression, shear and are poor, low mechanical strength, high-risk expansion of water, softening and collapse of shale and water will have a long-term effect of the role of mud. Weakende to some extent, the project mudstone traits, reducing the stability of the red bed slope, so the red layer of water-rock interaction study of aging has important practical significance. In this paper, the red beds in the reservoir area of the Sichuan Basin grinding rock sample tests, scanning electron microscopy, disintegration testing, mechanical testing and moisture content of the system test, revealing the red layer of water-rock interaction with tme-sensitive, and understanding the following points:⑴The result of water-rock is related to lithology and its components:mudstone, clay and other rock soft rock in the water under high physical and chemical changes, mainly due to the kaolinite,illite and montmorillionite and other mineral-based, which has strong hydrophilicity, water infiltration in the circumstances of its structure easier to mud, and rock to soften the impact of its project to the overall stability, and water on sandstone, siltstone relatively weak impact on.⑵After the red layer with the collapse of water: the collapse of the speed and degree of weathering, lithology and water and time factors. Collapse of the role of weathering of mudstone in strong performance, particularly, on the contrary weak mudstone weathering the slow disintegration; higer clay content of the rocks of its rapid collapse, after the water was layered spalling, disintegration is obvious, and sandstone is a slow distintegration.⑶The water-rock interaction of red beds weak on the mechanical properties: weathering test revealed a weak stem red rock saturated with higher compressive strength and strength after a sharp reduction, and similar to previous findings, softening coefficient about 0.5～0.55.⑷The water-rock interaction of red beds has timeliness: the longer the water, the more lower rock strength, but the development stage, started to decline rapidly, then stabilized. Softening of the overall coefficient of between 0.3 to 0.5, after 30～50 years after the reservoir water softening coefficient than the current measured in the laboratory to reduce 10～20%.⑸Long-term storage of water in the reservoir area-rock slope will reduce the stability of reservoir banks. When full of water and low-flow changes in water level fluctuation, not only to changes in loads of rock, hollowed out so that it faces the danger of erosion of rock, the gap containing the water-based changes in the overall stability of the rock mass will also have effect, thus attecting the stability of the reservoir bank slope.To sum up, the water-rock interaction study of both theory and engineering practice, has its significance, especially in water abundant areas of red beds. Mudstone in the role of water under the softening, of the role of mud on the rock properties and reservoir banks of the foundation works of the project will pose a threat to stability. This article on a pilot study for the main method for the mudstones of the four sub-tests and found that water on the rock of immersion in the life of a different impact on different shows the characteristics of its timeliness; water of different lithologic immersion in the same impact on life is different, showing the water-rock interaction and the characteristics of lithology; rock in the wet and dry after the turn of the accelerated destruction of changes, shows the characteristics of its collapse.
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