how to repair structural cracks in concrete
1.how to repair structural cracks in concrete?
1)Identifying: Select area need to be repaired.
2)Cleaning:Clean out crushed stone, dust etc cleanly within area need to be repaired by high pressure blower gun.
3)Washing:Thoroughly wash area need to be repaired cleanly by high pressure water gun,
It should rush mud out from operation surface when wash. .
4)Wetting: After wash cleanly by water,it should keep water in operation surface for a period time.
Fully wetting operation surface, until it is no longer seep water.
5)Cleaning: Clean water out from operation surface by high pressure blower gun.(If have water,it will seriously affect material adhesive property,compressive strength and beauty)
6)Adding water: Mix SC type concrete repair material and water then stir, effect is best when water added 17%-18%.
7)Mixing: It must fully stir evenly when stir by vertical mixer.
8)Paving:Pour mixed repair material to operation surface need repair, flattening by darby immediately.
2.Repair effect of structural cracks in concrete:
1)Beautiful,small color difference,Joint tightly after repair
2)Fast setting,1 hour open to traffic after repaired, reduce traffic jams.
3)High adhesion strength, high compressive & flexural. Good toughness
4)Impact resistance strength is more than 5 times of normal concrete.
5)Waterproof anti-freeze,heat expansion and cold contraction is nearly same. Service life is much longer.
3.Testing data to repair concrete structure crack:
Test items | Unit | Technical requirement | Test result | Individual conclusion | |
Setting time | Initial setting | Min | ≥20 | 25 | Meet requirement |
Final setting | ≤60 | 35 | |||
Compressive strength | 4h | Mpa | ≥20 | 33.0 | Meet requirement |
1d | ≥40 | 66.1 | |||
28d | ≥50 | 90.5 | |||
Pull strength | 28d | Mpa | ≥2.0 | 2.8 | Meet requirement |
Expansion rate | 28d | / | 0.00%-0.1% | 0.01% | Meet requirement |
