Effect of Plastic Fines on Undrained Resistance of Anzali Sand

Document Type : Research Article


1 M.Sc. Student, Campus of the the Guilan University, Iran

2 Assistant Professor, Department of Engineering, Guilan University, Iran

3 Assistant Professor, Geotechnical Engineering Research Center, International Institute of Earthquake Engineering


In this regard, plastic fines have been added to Anzali sand with diverse proportions and then triaxial monotonic tests have been implemented to find that how these fine contents can affect the sand undrained shear behaviour. All the prepared samples had the same initial dry density and were subjected to two different confining pressures. The results show that, in comparison to the clean sand, increasing the content of plastic fines from 0 to 30% results in a decrease in the undrained shear resistance of the samples, wherease this trend is reversed for the values of fine contents greater than 30%. In addition, the effect of plastic fines on the pore pressure generation was studied in the saturated sands. The results reveal that the specimens having up to 30% plastic fine contents generated larger values of pore water pressure than clean sand specimens. And for the larger amounts of fine contents, the excess pore water pressure decreased comparing to the clean sand.


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