Under-compaction method for sample preparation of Boushehr carbonated silty sand

Document Type : Research Article


Department of Geotechnical Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran


Because of the impact of the void ratio parameter on liquefaction and static strength of sandy soils, the preparation of samples which are homogenous in their heights in monotonic and cyclic triaxial tests is an important issue. The under-compaction method is an extended preparation method of wet tamping that is a suitable procedure to make homogenous sandy soil with fines. In this research, the under-compaction method is used in order to prepare samples of carbonated silty sand from Boushehr port and a method called injection of gelatin solution is used to control the homogeneity of samples. In order to investigate the effect of silt content on the homogeneity of prepared samples, Boushehr carbonated sand is mixed with silt percent of 0 to 40%, and gelatin solution is injected into the samples. Results show that samples prepared with the under-compaction method are homogenous, also the variation of silt content, changes the parameter of reduced compaction percent of the first layer (Un). In silt percents 0 to 20%, the Un parameter is limited to 4 and 6%, and in silt percent of 30 to 40%, the Un parameter is obtained 6 and 8%. It can be concluded that in silt percent of 0, 10 and 20%, inter-granular voids of sandy soil are filled with silt particles, thus the first layer is compacted close to the desired density, and the final compacted sample is more homogenous than the samples with higher percent of silt.


Main Subjects

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