The Impact Radius of Improvement Due to Sand Compaction Pile

Due to the growing population and spreading urbanization in the past century, to obtain suitable ground for constructing infrastructures needs to improve the soil. The sand compaction pile (SCP) method is used to improve soft clay and loose sandy soil under water table that cause serious problems such as liquefaction and extreme settlement. This method is applied to construct compacted sand piles by vibration, dynamic impact or static excitation in soft ground. Sand compaction methods can modify or improve initial SPT-N value which one of the most important data often used to evaluate the in-situ soil properties. Application of SCP method for sandy soil: increasing bearing capacity, reducing settlement and preventing liquefaction and for clay soil: increasing bearing capacity, reducing settlement, increasing passive earth pressure, reducing active earth pressure, increasing horizontal resistance to pile and sheet wall. The impact radius of this method is so importance to design the economical arrangement pattern. The design procedure sand compaction pile is based on simple analytical calculation for different lengths of 3, 5 and 7m, in three densification types with 40%, 50% and 60% relative density in sandy soil, which not reach to a stiff layer. The model is analyzed in 2D-PLAXIS software. In this study is attend to impact radius densification pile surrounding soil, void ratio changes with depth before and after improvement and influence of pile length on improved area. The results is verified with previous researches. A new type of SCP method, used in urban area and limited project, is also introduced

کلیدواژه ها:

Sand compaction pile ، Improvement ، Liquefaction