Plugging Construction Technology

Construction Procedure

Look for cracks: for wet base, clean the water first; For dry base, clean surface dust. Look for cracks and mark along the seam with a pencil or chalk.

Drilling holes: According to the thickness of the concrete structure, about 50-150mm away from the crack, cross drilling holes on both sides along the direction of the crack. The diameter of the 14mm drilling hole should be crossed with the fracture section at 45°-70°, and the cross should be in the 1/2 range of the middle of the structure.

Buried water sealing needle: bury and tighten with tools to ensure that the rubber part of the needle and the hole wall are absolutely matched, otherwise it is easy to cause slipping when tightening.

Precautions Before Construction

◆ First of all, the crack should be analyzed, and cored according to the different width and length of the crack to determine the development law of the crack depth.

◆If the surface is not easy to dry, it can be dried by blowtorch, and if there is water in the crack, it can be found immediately to improve efficiency.

Crack Repair

◆ The grouting slurry should be poured from the bottom up on the structure facade. When the slurry emerges from the crack, it should be stopped immediately and carried forward successively. In the process of grouting, if the slurry has filled the adjacent needle position, it can be jumped without note: if it is found that there are still cracks extending at both ends of the crack after grouting, or there are cracks crossing with it, re-grouting.

◆In order to fill the crack completely with grout, secondary grouting should be performed before the grout sets.

Precautions for Grouting

★ When a needle is injected for a long time (about 5 minutes), the slurry still does not emerge from the crack, should be stopped perfusion, interval after a period of time, if still not filled should check whether the drilling and buried pipeline cross, whether there are holes in the structure.

★ Perfusion should be closely focused on the working pressure gauge of the perfusion machine, such as exceeding the rated pressure (45Mpa or more), should be stopped after the shutdown, if the pressure is still high, should check whether the drilling and crack completely cross, drilling depth is greater than half of the structure thickness.

Crack Repair Inspection

The cracks that have been repaired are cored by drilling machine after 3 months. The test result should be that the concrete surface is smooth and dense, and the slurry is all filled with cracks, and the concrete strength and compressive test is carried out on the core sample to achieve the original design value.