Study on Probability Distribution Characteristics of Dynamic Shear Modulus and Damping Ratio of Red Clay

To investigate the dynamic parameter characteristics of red clay and reveal the probability distribution law of dynamic shear modulus ratio and damping ratio under typical shear strain conditions, taking the red clay in Guangxi province as the research object, 321 groups of basic data of dynamic characteristics test are collected and sorted out, and the test recommended relationship curves of dynamic shear modulus ratio (G/G_max) and damping ratio (λ) with shear strain under typical shear strain conditions are given, and the uncertainty distribution of dynamic modulus damping under different probability levels is analyzed. The upper and lower limit values and fitting formula of G/G_max under different probability levels are given by using the Boltzmann curve. The relationship between dynamic characteristics of red clay and depth and shear strain is preliminarily revealed by comparing with the research results of conventional soils given by predecessors. The results show that the upper and lower limits of the G/G_max and λ of red clay under typical shear strain conditions exhibit a certain pattern with the variation of exceedance probability, and the Boltzmann equation is applicable in mathematical form. When the shear strain is between 1 × 10^-4 to 1 × 10^-3, the dispersion degree of dynamic shear modulus ratio and damping ratio reaches the maximum. Under the same shear strain condition, with the increase of exceedance probability, the difference between the upper and lower limits of the G/G_max and λ of red clay significantly increases.