US Patent 9783987 Pre-tensioned centrifugal concrete structure with steel strands

A pre-tensioned centrifugal concrete pillar includes a concrete body, a steel cage including a plurality of pre-stressed rebars, a plurality of stirrups; and two plates, the rebars are steel strands, a plurality of conical through holes are provided on the plate, and multiple clips are disposed inside each conical through hole, each clip having a toothed inner surface, the multiple clips are spliced together to form a chock assembly for clamping each steel strand, and a peripheral surface of the chock assembly has a conical surface; a clamping hole is formed in the center of the chock assembly, the steel strand passes through a clamping hole and is clamped tightly. A method for manufacturing a pre-tensioned centrifugal concrete pillar is also included.