库区红层泥岩水化特性及干湿循环作用下的渐进损伤研究

库岸边坡长期受到大气循环、水位调节等水流往复运动而带来的渗透侵蚀影响.特别是在我国西南红层区的水利工程中,水的长期浸入和干湿循环作用导致红层泥岩特性出现严重的劣化.以川西南红层区某水库为工程依托,通过室内试验和理论分析深入研究了红层区泥岩的水化特性及干湿循环作用下的渐进损伤破坏.结果表明:红层泥岩发生水岩作用后微观结构...

Research on the Hydration Characteristics and Progressive Damage of Red Bed Mudstone under Dry-wet Cycle in Reservoir Areas

The bank slope of the reservoir is affected by seepage erosion caused by the reciprocating movement of water flow for a long time,such as atmospheric circulation and water level regulation.Especially in the water conservancy project in the red bed area in southwest China,the long-term water immersion and the dry-wet cycle result in the serious deterioration of the red bed mudstone characteristics.Based on a reservoir in the red bed area of southwest Sichuan Province,the hydration characteristics of red bed mudstone and progressive damage and failure under dry and wet cycles are deeply studied through laboratory tests and theoretical analysis.The results show that the microstructure of red bed mudstone becomes looser after water-rock interaction.The expansion and deformation of red mudstone in the initial stage of flooding is significant,and the vertical deformation of rock mass is further aggravated by the dry-wet cycle.The compressive strength and cohesion of the red-bed mudstone decrease linearly with the number of dry and wet cycles and decrease with the concave quadratic function respectively,and the angle of internal friction increase slightly with the increase in the number of cycles.Both confining pressure and the number of dry and wet cycles have a great adverse effect on the progressive damage accumulation of red-bed mudstone.When the cycles are over 3 times,the damage variable value of samples under different working conditions generally exceeds 60%,the strength of the rock mass is greatly reduced.