Effects of periodic saturation on K0 for a sandstone-mudstone particle mixture

Abstract

Sandstone-mudstone particle mixture (SMPM) is one of the main materials, which has been widely used for filling in and around reservoirs for water conservation projects. During the periodic rising and falling of the water level, the fill material for the embankments, dam, and other waterfront features will also undergo drainage-saturation cycles. The deformation and coefficient of lateral pressure at rest K0 may be affected by periodic saturation. In this study, a device is modified for testing the K0 for gravel-soil under periodic saturation. In order to investigate the effects of periodic saturation on K0, a series of experiments were performed for SMPM under different vertical stress and saturation cycling. K0N values of SMPM containing 20% mudstone particles under periodic saturation were obtained. The results shows that the K0N initially increased, but eventually reached a stable value with the increasing number of periodic saturation cycles. The magnitude of the coefficient increment was also found to be related to the stress condition. K0N is a logarithmic function of the saturation cycling time. By calculating K0N with the proposed empirical formula, the deformation and stress distribution of the SMPM filler in waterfront engineering works can be calculated with greater precision.