Study on Geotechnical Properties of Sediment Deposited in Latian Dam Reservoir Using Field Measurements

This study aims to investigate and analyze the results of geotechnical experiments on sediment samples taken from the Latian Dam reservoir in Tehran province. After the site visit, eight important stations were identified for surface sediment sampling, and on these sediments, common soil mechanics tests such as grain size analysis, determination of specific gravity, consolidation, compaction, and triaxial were performed to determine soil resistance and consolidation parameters. The present study results showed that by approaching the dam wall, soil water content increased by more than two times. This is due to the smaller size of the soil grains so that the percentage of clay and silt near the dam wall was more than 89%. According to the compaction test results and empirical equations, it was found that after 100 years of sediment deposition in the Latian dam reservoir, the dry density of the sediment will be equal to 1.128 g/cm3. In addition, from the triaxial test results, it was found that the cohesion and internal friction angle parameters of the sediments were equal to 0.51 kg/cm2 and 26.1°, respectively.