The prestress engineering of Daya Bay nuclear power plant reactor containment vessel adopts the French standard Freyssinet Monogroup system, with steel strands composed of 19 or 36 T16 wires threaded through rigid or semi-rigid ducts for post-tensioning. The containment prestress is divided into three systems: horizontal, vertical and dome. The horizontal direction uses 360° full circumferential layout, and strand tensioning must follow strict sequence. To prevent strand corrosion, slow-setting cement grout is injected into ducts after tensioning.