Abstract: An annular assembly, or ring cell, is provided for testing the load bearing capacity of piles. The ring cell walls of the annular assembly can be made of stamped material. The ring cell walls can be an outer ring wall and an inner ring wall. Alternately, the ring cell walls can have a “U”-type shape cross-section including an outer ring wall, an inner ring wall, and a top wall. Fluid can be provided to the annular assembly through fluid supply lines into an expansion zone. The expansion zone can be a space having a bladder for filling with fluid. In another embodiment, the expansion zone can be a space between a filler material capable of withstanding high pressure separated with a membrane. The pressure of the fluid in the expansion zone can be monitored during testing.