Abstract
Because of the scarcity of land for urbanization, multistoried construction projects are becoming a preferred choice. Such projects more often require soil reinforcement or ground improvement to strengthen the soil and reduce the foundation settlement of structure to meet the project demanding standards. Micropiles have been used as one of the simplest ground improvement methods for a long time. The micropile also finds its applicability in the retrofitting of old structural foundations. The present study has been carried out for laboratory scaled model to investigate the efficiency of the micropiles to strengthen the soil and reduce the foundation settlement of structure constructed on Indian flyash. The efficiency of micropiles has been studied when used as a group, for stress versus displacement characteristic of the surface footing. Next, a 2D finite element analysis of the same model has also been carried out in GeoStudio 2016. The efficiency of micropile groups has been investigated for the slenderness ratio of micropile with value as 60, 80, 100 and 120. The study concluded that the slenderness ratio of micropile has a substantial effect on the bearing capacity of flyash. Moreover, quantitative improvement in the bearing capacity of the flyash has been determined in terms of a factor known as bearing capacity ratio (BCR). The BCR value is found to be greater than 1 in each studied case of the micropile group having a different slenderness ratio.