Abstract: A system for field testing the bearing behavior of a test helical pile employs a plurality of anchor helical piles driven into the ground at angles around the test helical pile and a head assembly to form a support structure over the test pile. The head assembly includes attachments for engaging the upper ends of the anchor helical piles, and a vertical passageway extending through the head assembly. A hollow-core hydraulic jack having a vertical passageway is inserted between the upper end of the test helical pile and the head assembly to exert a test load on the test helical pile. A vertical member is placed through the vertical passageways in the head assembly and jack to the upper end of the test helical pile to measure movement of the test helical pile in response to the test load.