English：

To realize the high-quality drilling of a high-speed railway bridge pile foundation with more than 100 meters in water on the deep overburden layer of the Yellow River, combined with engineering experience, the steel pipe pile and Bailey beam are designed to form a steel trestle drilling operation platform, and the combined drilling of crawler reverse circulation and air lift reverse circulation drilling rigs is adopted. The length of the steel casing is appropriately deepened, and the embedded depth is 14 ~ 21 m. The bottom wall thickness of the steel casing is increased to 22 mm, or the bottom is hemmed. The steel casing is buried by the guide frame. When the drilling depth is within 30 m, the density, viscosity, and sand content of the wall-protecting slurry gradually increase with the increase in the drilling depth. When the drilling depth is more than 50 m, the density, viscosity, and sand content of the wall- protecting slurry are basically unchanged. When the hole collapse is slight, cement, bentonite, and sawdust are filled to increase the relative density of slurry, enhance the slurry wall protection, and control the drilling speed. Paste drillings can be manually treated by shaking the drill bit up and down and lifting the drill to the surface, if necessary. The ultrasonic detector is used to detect the quality of the ultra- hundred-meter drilling hole, and the quality of the hole is found to be excellent.