JavaScript must be enabled in order to use this site.Please enable JavaScript in your browser and refresh the page. Driller Pier Theory (Axial Load Analysis) The following methods are used by the program to determine the axial capacity of a drilled pier. 8.12.1 API Method 8.12.2 FHWA Method 8.12.3 Vesic Method Parent topic: Technical Reference Related conceptsDrilled/Driven Pier Foundation Drilled Pier