To investigate the mechanical properties of coarse-grained soil in red-bed deposits under triaxial loading and unloading conditions,triaxial compression tests involving loading-unloading-reloading cycles were conducted on two types of coarse-grained soil samples from a slope featuring red-bed deposits in Sichuan Province.The tests yielded strength and deformation characteristics of the specimens under various loading and unloading scenarios,revealing the features of unload recovery modulus and its relationship with confining pressure and stress levels during unloading.The results indicate that:(1)The coarse-grained soil samples from the studied red bed deposits exhibit characteristics consistent with the Duncan-Chang constitutive model under triaxial compression.(2)The normalized unload recovery modulus,based on standard atmospheric pressure,exhibits a positive linear correlation with the normalized confining pressure.(3)The dimensionless coefficient nur representing the unloading rebound modulus during the unloading phase is not equal to the dimensionless coefficient n characterizing the initial tangent modulus during the loading phase.(4)With regard to the influence on the unloading rebound modulus,there is no collinearity between the confining pressure and the stress level during unloading,with the confining pressure having a more significant effect.(5)The rebound modulus of the tested coarse-grained soil samples is approximately 3.5 to 4 times that of the initial tangent modulus,significantly greater than the corresponding values for clays.These findings provide valuable insights into the understanding of the mechanical properties of coarse-grained soils in red-bed deposits.
red-bed depositscoarse-grained soiltriaxial compression testDuncan-Chang modelloading-unloading process
万方数据
维普
