1. First, remove the loosened aggregates and concrete particles from the affected surface by using a wire brush and a chipping hammer.
2. Clean the surface thoroughly with a brush to remove finer particles and then wash the surface with water.
3. Let the surface to dry well and apply Chemi-fix glue on the area.
4. Now mix the concrete grout with white cement and add required amount of water ( as per the specification recommended by the manufacturer).
5. Then pour/paste the mixture in the affected area to fill it completely. In case of large honeycomb, the concrete mixture should be poured after creating a pocket.
6. Remove the formwork after 12 hours and then cure it well.