Static skin friction behavior of a single micropile in sand

Numerical pile segment analyses were conducted using an advanced soil model to investigate the development of side resistance and the soil behavior around a micropile installed in sand and subjected to static axial loading. A series of static pile segment analyses were performed for micropiles and Conventional Drilled Cast-In-Place (CDCIP) piles considering effects of pile installation, relative density of sand and pile diameter. Results of analyses were used to determine the effects of pile installation, pile diameter, and relative density of sand on static shear behavior of a micropile and changes in effective stresses and volumetric strains in the soil adjacent to the interface. Relatively high side resistance and stiff t-z response were characteristic features of a micropile compared with CDCIP piles. Results of static numerical pile segment analyses for micropiles were compared and found to exhibit good agreement with pile loading tests and design methods.