Stability analysis of soils prone to static liquefaction based on their monotonic undrained shear strength characteristics is an indispensable challenge in earthquake geotechnical engineering. This paper presents a laboratory study on the static behavior of Chlef sand–silt mixtures (with a silt content fc range from 0 to 50%); under low confining pressures. The experimental program includes undrained triaxial monotonic tests which were carried out for five types of samples, consolidated under different confining pressures (σʹ_c = 20, 50, 100, 150, and 200 kPa). On the samples preparation, the dry pluviation funnel has been used with a medium relative density (Dr = 60%). Main results obtained indicate that the fines content and initial confining pressure have a significant influence on instability stress and steady-state ratios of sand–silt mixtures. Moreover, the obtained data confirm the existence of a simple correlation between undrained instability stress, steady-state ratios, fines content, void ratios, and effective confining pressure. From the results obtained, nevertheless it can be concluded that the global void ratio does not represent the actual behavior of the soil under study, and the undrained residual strength decreases with a logarithmic manner with the increase of the intergranular void ratio, and a similar trend is occurring with the fine content of the sand–silt mixtures up to 50% as well.

基于单调不排水抗剪强度特性的易于液化的土壤稳定性分析是地震岩土工程中不可或缺的挑战。本文介绍了Chlef砂-粉砂混合物（粉砂含量fc为0至50％）的静态行为的实验室研究；在低围压下。实验方案包括测定其五种类型的样品的情况下进行不排水三轴单调测试，不同围压下固结（σ ' _Ç = 20、50、100、150和200 kPa）。在样品制备中，使用了干浸液漏斗，其相对密度为中等（Dr = 60％）。获得的主要结果表明，细粉含量和初始围压对砂-粉混合物的不稳定性应力和稳态比有显着影响。而且，获得的数据证实了不排水的不稳定性应力，稳态比，细粉含量，空隙比和有效围压之间存在简单的相关性。然而，从获得的结果可以得出结论，总孔隙率并不代表所研究土壤的实际行为，不排水的残余强度随晶间孔隙率的增加以对数方式降低，