In July 2020, Taixin Machinery’s ace models KR285C and KR220C formally entered the nuclear power site in Zhangzhou, Fujian.
The project was undertaken by China Nuclear Industry Fifth Construction Co., Ltd., and the project is a comprehensive warehouse component of the 1516 project. The number of piles is 768, the diameter is 800mm, and the effective pile length is 33 meters. The current construction technology is multifunctional long spiral + DTH hammer + Rotary drilling rig cooperates to form piles. The construction site is quite complicated, with backfilled stones, silt, sea sand, and granite fully weathered and strongly weathered. In response to this situation, the Thai letter construction team made a detailed construction plan: about 0 meters to 22 meters, we use multifunctional long spirals. +24-meter protection tube under the down-the-hole hammer, effectively avoiding the risk of hole collapse in the formation. During pouring, the vibrating hammer pulls out the protective tube. The concrete loss in the pile in the formation is serious, which improves the filling coefficient of the pile. When the protective tube is lowered by the DTH hammer, we backfill the viscous sand several times to compact the periphery of the protective tube, thereby reducing the filling coefficient. About 22 meters to 31 meters belong to the geology of easy collapse holes. We use the prepared bentonite in the grouting hole to effectively avoid the collapse of the stratum and excessive sedimentation.After more than a month of hard work, the current construction efficiency has been greatly improved, and the construction method has been highly recognized by the supervisor.