Using Crackamite: Hole Filling
Immediately after mixing the Crackamite powder into proper slurry, pre-drilled holes need to be filled with the Crackamite paste.
Filling of the holes with Crackamite
Please observe the following points while filling the pre-drilled holes with Crackamite:
- Crackamite should be poured into holes within 10 minutes after mixing with water. The Crackamite mixture may loose fluidity within 10 minutes of mixing and will become difficult to pour. Once its fluidity is gone, it should not be diluted by re-mixing with water, as its strength is reduced. Longer mixing time will cause blow-outs.
- Crackamite is best filled using a bucket with spout or funnel. For a horizontal hole use a grout pump. Drill horizontal holes with some slope to help in filling.
- Crackamite must be poured into every hole upto the brim.
- For a horizontal hole, the hole can be easily plugged with Crackamite as it reaches clay like consistency as it starts setting.
Use of polythene sack in hole
- If there is water in the hole, place a thin polythene sack equal to the hole diameter into the hole, insert a wooden rod into the bag and then fill Crackamite into the sack. Crackamite in the sack will displace the water in the hole. There is no change in the cracking strength by the use of this kind of sack.
- When there are many joints or large voids/holes in the material to be cracked or when Crackamite leaks from the hole, use the sack method.
- When a lot of the water in the Crackamite slurry is being absorbed into the material being cracked (for instance, a dry concrete), use the sack method or alternatively, spray water. However, in cold temperature, avoid pouring water as it may freeze in the hole.
- When the material to be cracked is immersed in water, use the sack method. Use a bucket or pump when filling the sack and then seal the sack from the top to avoid Crackamite slurry dilution. If there is no flow of water around the mouth of the holes, Crackamite may be directly poured into the holes using the pump. This should gently displace the water in the hole.
After Treatment
- DO NOT leave excess Crackamite slurry in the bucket as blow-outs may occur.
- Tamping with mortar or sand is not required after filling with Crackamite slurry. It is also not necessary to put any kind of restrictive cap. Just leave it as it is and wait until cracks initiate. Covering the filled hole with tarpaulin is desirable to avoid dilution of Crackamite slurry from external water source until cracking starts.
- Spraying the surface with water, after the cracks initiate, tends to increase the width of cracks and speeds up the cracking process.