Prestressed pipe pressure slurry vacuum grouting principle and preparation

Prestressed pipe pressure slurry vacuum grouting, the principle of vacuum grouting in grouting before first use vacuum pump suction prestressed duct in the air, make the vacuum inside the hole above 80%, and then at the other end of the tunnel grouting machine to greater than zero. 7 mpa positive pressure to press the prestressed pipe pressure slurry into prestressed channel. It is difficult to form bubbles; At the same time, due to the positive and negative pressure difference between the hole and grouting machine, greatly improving the hole grouting plumpness and compaction. In cement slurry, reduce the water cement ratio, added dedicated to add the seam an agent, to improve the fluidity of cement slurry, reduce the shrinkage of cement slurry. Second, the construction equipment in addition to the traditional grouting construction equipment, vacuum grouting also need the following equipment: 1, vacuum pump, pressure gauge and control panel; 2, pressure tanks, can be used as a protective barrier to prevent damage of slurry mixture into a vacuum pump and vacuum pump. 3, clean reinforced secrete water pipes, able to withstand greater pressure; 4, air valve and air tight anchor cap.