Methodology of Concrete Repair Work

What is Concrete Repair?

• Concrete repair is the process of fixing a hardened concrete surface that over time has lost the ability to hold the binding concrete materials together due to damage or environmental exposure. Concrete repair is appropriate for cracks, physical impacts, chipped out surfaces or surface scaling

1. Method of Repair the Bug holes & Plucked surface

1. Outline the surface defect with a 10 to 20mm-deep saw cut.
2. Remove defective concrete down to sound concrete.
3. When chipping, leave chipped edges perpendicular to surface or slightly undercut. Do not feather edges.
4. Clean substrate and remove all loose material, dust, etc.
5. Prepare cream of approved repairing material as specified in the material data sheet.
6. Strike off mortar, leaving the patch slightly higher than the surrounding surface to compensate for shrinkage.
7. Leave the patch undisturbed for 1 hour, then finish to match the texture of the surrounding concrete.
8. Keep the patch damp for 7 days.

2. Method of Repair the Bulging

1. The surface shall be identified and marked for the repair.
2. The bulging area shall be cut with cutter in plumb and align vertical. The depth of shall be min 10mm from required finished surface of concrete.
3. The identified area shall be cleaned for delaminated, weak & damaged concrete.
4. The surface shall be cleaned for dust, loose & other materials affecting the proper bond.
5. The surface shall be uniformly hacked to obtain adequate key.
6. Concrete surface shall be washed with clean water.
7. The surface shall be thoroughly dampened.
8. Approved bonding agent shall be prepared as per the datasheet and shall be applied by brush.
9. Then repair mortar Renderoc HsXtra or as per site specific High Strength Shrinkage compensated material shall be prepared and applied by mason trowel.
10. Surface shall be uniformly and smoothly finished.
11. Curing shall be done by curing compound or site specific.

3. Method of Repair the Honeycombs

1. Remove loose particles and clean the surface properly
2. Follow the procedure for mixing as per manufacturer
3. Apply rusticide if any steel exposed
4. Apply Nitobond AR
5. Fill with mixed past and finish with trowel
6. Curing by at least minimum 3 Days

4. Method of Repair the slab surface crack

1. All area to be repaired shall be marked out
2. The entire length of the crack to be notched out “V” shape at about 3 to 6mm deep.
3. Apply and finish by non-shrink polymer modified mortar mortar (ex-Fosroc Conbextra GP2, Renderoc FC / SIKA CRACK SIL / EMMACO R307).
4. Let the compound cure as directed / as specified in TDS.
5. Do pond test for 48 hrs. to check water tightness of slab. Ponding thickness 3’’.
6. If the crack is more than 1mm wide, need to consult with structural consultant for repaired methodology with appropriate root cause.