1. The grouting process plan shall include the following contents:
1) Determination of slurry mix ratio, grouting volume and pressure
2) Equipment for preparing and conveying slurry and its installation
3) Grouting process, grouting system and layout of grouting holes
2. Ensure that a stable and continuous slurry sleeve can be formed in the gap between the outer wall of the pipe and the soil during jacking
3. The selection, composition and technical index requirements of slurry materials shall be determined through field tests; for synchronous grouting at the tail of the pipe jacking machine, materials with relatively high viscosity, small water loss and good stability should preferably be selected; materials for supplementary grouting should preferably have low viscosity and good fluidity
4. Thixotropic slurry shall be stirred evenly and have the following properties:
1) It should be a colloidal liquid during conveying and grouting, with corresponding fluidity
2) After grouting and a certain standing time, it should be in a gelled state and have a certain consolidation strength
3) During pipe jacking, after the thixotropic slurry is disturbed and its gelled structure is destroyed, it should still be a colloidal liquid
4) Thixotropic slurry materials are harmless to the environment
5. Grouting holes should be continuously provided in several pipe sections following the tail of the pipe jacking machine
6. The principles of "combining synchronous grouting with supplementary grouting" and "grouting before jacking, grouting while jacking, and timely supplementary grouting" should be followed to formulate a reasonable grouting process
7. During construction, the viscosity, unit weight, pH value, grouting pressure and grouting volume of the thixotropic slurry should be tested.