Pull-out capacity of multi-helix screw pile in organic soil

In this study, the performance of multi-helix plate piles under pull-out load in organic soils is tested through an experimental investigation on helical piles. Tests were carried out on rigid helical piles with different numbers of plates. The helix piles were made of 16 mm diameter mild steel shafts to which mild steel plates of 50 mm for both diameter and pitch were welded. Tests were performed on single, double, triple, and quadrable-helix cylindrical screw piles with helix spacing to diameter ratios varying from 0.1 to 0.5. A set of tests was also performed to evaluate efficiency. The results of the tests are used to illustrate the difference in ultimate capacity for the different geometry anchors. The results showed that the helical piles behavior depends essentially on pile geometric characteristics and soil density. According to the achievements, pull-out load capacity of helical piles depends on spacing ratio (S/D) and number of plates. Key Words: helical pile, organic soil, pull-out capacity, pile efficiency