A Model Study on Effect of Pattern on Group Efficiency of Micropile

The micropiles are small diameter (100-300mm) non displacement piles. It can be favored over conventional piles, because they can be drilled under difficult subsoil conditions, where conventional piles cannot be constructed, and can be used for strengthening the existing foundation or retrofitting. The capacity of micropiles depends on the micropile size and subsurface profile. In this study, the effect of pattern on group efficiency of micropiles on sand was studied. Load test was carried out on a model footing resting on sand with and without Micropiles. Group efficiencies of micropile groups having 20mm diameter spaced at 2D, 3D and 4D, where D is the diameter of the micropile, arranged in triangular and square pattern were determined. The preservation of natural aggregate is also an aim of this study. In order to preserve this naturally available material, the micropile is casted by replacing the fine aggregate with 2 % of PET bottle fiber.