# Effect of Plastic Fine Content on the Static Liquefaction Potential of Sandy Soil
[PERSON]  
2 Universite Gustave Eiffel, IPSITAR (GERS/SRO), 77420 Champs sur Marne, France; [EMAIL_ADDRESS]  
[PERSON]  
3 Institute of Research and Development, Duy Tan University, Dang 550000, Vietnam 34 Faculty of Civil Engineering, Duy Tan University, Dang 550000, Vietnam 45 Laboratory for Computational Mechanics, Institute for Computational Science and Artificial Intelligence, Van Lang University, Ho Chi Minh City 70000, Vietnam; [EMAIL_ADDRESS]  
[PERSON]  
5 Laboratory for Computational Mechanics, Institute for Computational Science and Artificial Intelligence, Van Lang University, Ho Chi Minh City 70000, Vietnam; [EMAIL_ADDRESS]  
[PERSON]  
1 Department of Infrastructure Engineering, Hanoi University of Mining and Geology, Hanoi 100000, Vietnam; [EMAIL_ADDRESS] (Q-H.D. ); [EMAIL_ADDRESS] (V-H.P.) [PERSON]  
2 Universite Gustave Eiffel, IPSITAR (GERS/SRO), 77420 Champs sur Marne, France; [EMAIL_ADDRESS]  
[PERSON]  
3 Institute of Research and Development, Duy Tan University, Dang 550000, Vietnam 34 FacultyMeanwhile, other works [17; 19; 20; 21; 22; 23; 24; 25; 26] found adverse effects of fine content on the undrained liquefaction resistance of sand-fines mixture. In addition, some scholars reported that an increase in fine content, to a threshold, leads to an increase in undrained shear strength, which is followed by a decrease in the static liquefaction susceptibility beyond this threshold of fine content (e.g., [16; 27; 28; 29; 30; 31; 32; 33]). These different tendencies may be attributed to the choice of the parameter to characterize the undrained shear resistance of silty sand (e.g., intergranular void ratio, global void ratio, initial relative density index, etc. ), the fine content natural (plastic or non-plastic added materials), the reconstituted sample method, the gradation characteristic, the grain shape, and the plasticity index. For instance, the impact of added particles cannot be captured by the global void ratio [18]. [PERSON] [17] studied the effect of two fine materials, C500 (silty non-plastic fine) and Speswhite (clayey plastic fine), and reported that the increase in the non-plastic fine amount exhibits a beneficial effect on the static liquefaction resistance, while the plastic fine leads to an adverse impact. However, [PERSON] [17] used two reconstituted sample methods: the wet tamping method for the sand-C500 mixture and the dry tamping method for the mixture of sand and Speswhite. [PERSON] et al. [18] and [PERSON] et al. [26] considered a similar mixture: clean Hostun-RF and (HN31) and Silica C500 fines. However, the sample was reconstituted by the moist tamping method in [PERSON] et al. [18] and they reported an increase in static liquefaction resistance versus an increase in C500 amount. Meanwhile, [PERSON] et al. [26] adopted the dry tamping technique for the reconstitution of the sample and they showed an adverse effect of added particles on the undrained shear strength. [PERSON] and [PERSON] [34] showed that an increase in added material plasticity index up to a threshold value leads to, firstly, a decrease in undrained shear strength, and beyond this threshold, an increase in undrained resistance is observed. [PERSON] and [PERSON] [35] investigated the effect of added particle shape and showed that rounded silt yields a lower undrained shear strength of the silty sand mixture, in comparison with angular silt. Nevertheless, [PERSON] et al. [36] reported an opposite trend that angular silt makes the silt sand mixture sample more prone to liquefaction. These non-consensus conclusions in the literature emphasize that the effect of fine content on the liquefaction potential can be different from one sand to another and also depends on the laboratory test procedure. In other words, the conclusions drawn from studies focused on other sandy soils cannot be applied to the considered one. This work investigates the undrained behavior of Fontainebleau clean sand and mixtures of this sand and fine plastic particles via static triaxial tests.