1, for small area concrete surface with pits:
First, chisel the pockmarked surface to a dense place, clean it with clear water, then spray water on the concrete surface with a watering can until it is saturated, and then evenly spread the prepared cement dry ash on the surface. This process should be repeated until all the defective places are covered with cement ash. After curing for 24 h, the cement ash protruding from the lining surface will be removed with trowel, and then the details will be repaired according to the method of plastering cement ash to ensure the smooth and dense concrete surface.
2. For large-area honeycomb exposure:
Chisel away concrete and protruding stones, which will not be lost at the honeycomb; Clean it with a wire brush, and sprinkle water to fully wet it. Repair it with fine stone concrete whose strength is one grade higher than that of the original concrete, and vibrate it carefully for compaction. Strengthen maintenance after repair, and smooth it with a grinding wheel after the maintenance period. Mix the cement slurry with white cement, and brush the pure slurry surface with paint brush.
3. For missing edges and corners:
Treatment scheme of local rotten corners and exposed tendons. First, clean up the loose stones and laitance around, then trim the steel bar, and then support the corner formwork for watering and wetting, and repair it with high-grade fine stone expansive commercial concrete.
4, the mouth of the cave:
Hole repair method: firstly, the loose part of the hole is chiseled to form a regular shape; Remove the dust and debris from the damaged area with a wire brush; Blow clean the repair surface with compressed air; Rinse the repair surface with water to make the concrete around the repair surface fully wet; Filling the selected repair materials, vibrating, compacting and smoothing; For maintenance.
5. Mould:
Firstly, the concrete in the swelling part of the formwork is chiseled away to repair the cement mortar with the same mixture ratio in concrete. After the repair, the maintenance was strengthened. After the curing period, it shall be polished with a grinding wheel, mixed with uniform cement, and brushed with pure cement slurry with a paint brush.
6. Exposure:
Generally, the repair is to delimit the area to be treated with a saw groove to form a neat and regular edge, and then use an impact tool to remove loose concrete within the treatment range. After the exposed steel bars on the surface are cleaned, the exposed steel bars shall be leveled with 1:2 or 1:2.5 cement mortar and carefully maintained. If the exposed reinforcement is deep, the weak concrete and protruding particles should be chiseled away, washed clean, filled with fine stone concrete with higher strength grade than the original, or repaired by shotcrete technology or pressure grouting technology, and carefully maintained.