1, base treatment: For the cast-in-place concrete wall, due to the floor, materials, isolation agent and other reasons, the flatness of the wall is poor, and there are often phenomena such as porosity, honeycomb, pits, unsmooth angle of yin and yang, arching and so on. Therefore, it is required that the convex parts should be polished and leveled, and the concave parts should be filled and filled. For precast concrete floor slab and slab joint base, it must be painted by special person with wire brush to remove impurities such as floating sand, bumps and dust on the surface. The grey surface of cement mortar paper reinforcement requires the surface base to be dry, solid and clean (no floating soil and oil stain).

2. Repair at the grass-roots level: After the joints of concrete roof panels are cleaned, the gypsum putty shall be leveled and compacted with a steel scraper for the parts with large defects such as honeycomb, and leveled horizontally (the top surface with smooth surface can be leveled). The proportion (weight ratio) of gypsum putty is gypsum: emulsion: cellulose aqueous solution (concentration 5%) = 100: 5 ~ 6: 60. Brush caustic soda solution: brush twice with 5% caustic soda solution and once with 10% concentration. Rinse with clear water immediately after brushing, and then proceed to the next process after drying.

3. Coating adhesive (juice slurry): Before scraping putty, spray a layer of adhesive, which must be uniform. The proportion (weight ratio) of non-leakage adhesive is clear water: emulsion = 100: 15 ~ 20. Scraping putty: Scrape putty back and forth with a steel scraper. Pay attention to the top, bottom, left and right. The space between the two scrapers should be clean, and floating putty is not allowed. When scraping putty, it is necessary to prevent it from being stained with or mixed with sand. The proportion (weight ratio) of white putty is: white powder: talcum powder: cellulose solution (concentration 5%): emulsion = 60: 4o: 75: 2 ~ 4.

4. Repair and polishing: After scraping the putty for the first time, the parts that have been repaired first should be re-inspected. If there is any problem, the collapsed part should be repaired and leveled with putty. After the putty is dry, it should be polished, smoothed and swept with sandpaper.

5. putty survival: scrape the white putty twice, and scrape it again after the first putty is dry. It is generally required to survive at least twice. It is required that the surface is not only flat, but also uniform in texture and texture, otherwise it is easy to have inconsistent colors and affect the decoration effect.