Effect of initial void ratio on the tensile strength of unsaturated silty soils

作者：Gao, You; Li, Ze; Cui, Wenjie^*; Sun, De'an^*; Yu, Haihao

来源：Acta Geotechnica, 2023, 18(7): 3609-3622.

DOI：10.1007/s11440-023-01800-z

• Initial void ratio
• Soil water characteristic curve
• Tensile strength
• Unsaturated soil

The tensile strength of unsaturated soils is a fundamental property in various geotechnical designs. Reliable estimation of the tensile strength of unsaturated soils, in particular fine-grained soils, is required in both theoretical research and engineering practice. Although several tensile strength models have been proposed in the literature, an overestimation may occur over a wide suction range, when applying them in the modelling of tensile strength of fine-grained soils. In this paper, the tensile strength of an unsaturated lean clay has been measured over a wide range of void ratio and water content by employing the Brazilian tensile strength test. A critical degree of saturation can be observed for specimens with different void ratios, at which the soil tensile strength reaches the peak. In addition, a predictive tensile strength model considering the effect of initial void ratio has been subsequently proposed for both coarse-grained and fine-grained unsaturated soils based on the interaction mechanisms between the adsorptive and capillary soil water. Finally, the proposed model has been demonstrated to be capable of modelling the tensile strength characteristic curve of various soil types ranging from clean sands to silty and clayey soils.

• 单位
  北京航空航天大学; 桂林理工大学; 上海大学