水载联合预压真空预压稳压后在预压区周边进行围堰覆水，围堰采用粘土围堰，

After the water load combined with preloading, <br><br>vacuum preloading and pressure stabilization, the cofferdam is covered with water around the preloading zone. The cofferdam adopts clay cofferdam with a height of 2.5 m, and the inside of the cofferdam is impervious with a special impermeable membrane. <br>Make sure that the vacuum pre-pressure is stabilized above 80 kPa for a period of time before water coating. The water-covering height is controlled at an average of 2.0 m, and after reaching the water-covering height, it should be no less than 70 days.

Waterborne joint prepressure<br><br>After vacuum pre-pressure regulation, the surrounding water is covered in the pre-pressure area, the enclosure is covered with clay, the height of the enclosure is 2.5 m, and the inner part of the enclosure is impermeable with a special impermeable film.<br>Make sure that the vacuum pre-regulated is above 80 kPa for a period of time before covering the water. The water cover height is controlled at an average of 2.0 m, and the water cover height is not less than 70 days of regulatory time.

Combined preloading with water load<br>After vacuum preloading and pressure stabilization, the cofferdam shall be covered with water around the preloading area. The cofferdam shall be clay cofferdam with a height of 2.5m, and a special anti-seepage membrane shall be used inside the cofferdam to prevent seepage.<br>Before covering the water, make sure that the vacuum preloading is stable at 80 kPa for a period of time. The water cover height shall be controlled at an average of 2.0 m, and the stabilization time shall not be less than 70 days after reaching the water cover height.