English：

The nuclear island containment vessel of a certain nuclear power project adopts the unbondedprestressing technology of “ grouting first and then tensioning” for the first time in China. The systemsignificantly reduces the friction coefficient through a quadruple protection design, and has functions suchas post stress monitoring, tensioning, and replaceable steel strands. The system elaborates on theresearch and application of this technology in key processes such as pipe burial, threading, grouting,tensioning, and anchoring,with a focus on introducing a series of technological innovations such assupporting construction platforms, new finished grouting materials, accurate measurement methods forfriction coefficients, and domestically produced equipment. Engineering practice has shown that thistechnology effectively improves construction efficiency, structural seismic performance, and flexibility forlater maintenance.