Analysis of Piles Performance in Soil and Settlement Able Mediums

The Tabriz city, as one of the metropolises of Iran, has a special geotechnical condition. In the northeastern part of Tabriz, due to the fine-grained soil layers and high groundwater level, a number of structures have been damaged. The Fereshteh town is one of the areas where in recent years unbalanced settlement of newly constructed buildings has been observed. With considering the importance of using pile-raft foundations, in this research by using the results of two boreholes in the Fereshteh area of Tabriz, the geotechnical characteristics of the soil have been evaluated. Subsequently, direct soil-structure interaction numerical models have been studied by Plaxis software. Based on the obtained results in this study, the minimum required length of piles in the pile-raft foundation system to change the status of the designation of structures from unauthorized to authorized, for 4 and 6-floor buildings is 6 meters and for the 8-story building is 8-meters. Also, in the 4, 6 and 8-floor buildings, respectively using 8, 10 and 12 meters for piles length is an optimal choice.