1 surface coating method
Polyurethane and epoxy resin are commonly used as surface coatings for cracks in shear walls. Here, taking epoxy mortar as an example, the construction points can be roughly divided into the following two points: ① Clean up the dust and residue on both sides of the crack surface of shear wall within the range of 150mm, and keep its surface dry; (2) Brush epoxy resin slurry repeatedly along the crack, and brush it every 4 meters or so until the thickness of the brush coating reaches 65438 0 mm. ..
2 grouting method
When grouting method is used, the commonly used materials are mainly epoxy resin, water-soluble polyurethane, methyl acrylate and so on. When using epoxy resin for construction, the construction points can be divided into the following points: ① Clean the crack surface first. Different from the above two cleaning methods, in addition to cleaning dust and residue, you should also dip alcohol, beard and acetone along the 25m range on both sides of the crack with a brush. (2) To bury the grouting nozzle, drilling may be better. If the crack width is greater than 1mm, the embedding distance is 35 ~ 50cm；; If the crack width is less than 1mm, the grouting nozzle spacing should be about 80cm, and there should be slurry inlet nozzle, exhaust nozzle and slurry outlet nozzle. (3) When sealing the cracks of each grouting nozzle with epoxy resin cement, if the cracks run through, they should also be sealed with epoxy resin cement. At the same time, after the cracks are closed, an air compression test should be conducted to check their tightness; (4) When grouting, the top-down grouting method should be adopted. When the next pulp discharge nozzle discharges pulp, the rotary core valve should be closed in time, and the pulp discharge nozzle is the next pulp inlet nozzle to take care of the circulating operation. If the slurry suction rate is less than 0, 1l/min during this process, the grouting should be stopped after injecting 1i, and the slurry inlet rotary core valve should be closed. After the initial setting of cement slurry in the crack is completed, the grouting nozzle can be removed and its position can be blocked with epoxy mortar.