Hello, everyone.
This is Enta.
先日から少し暖かくなってきました。
That said, it's still cold on set, lol.
Things are going to stay hectic for a little while longer, so please take care, everyone!
But that's beside the point.
This time, we'll be covering grouting in anchor work.
The grouting of the anchor bolts is the most important part, but,
That isEnsure that the anchoring section is constructed as an anchoring structureSince it won't function as an anchor unless you do this,
It's really important. Well, that goes without saying, right? (laughs)
Drilling Complete
↓
Inner Casing Recovery
↓
Anchor Text Insertion+Inserting the Injection Hose
↓
Injection
That is the procedure.
What's the most important thing here!?
That's the last injection.
Be sure to inject the material at the deepest point (bottom) of the anchor borehole....and so on.
For example, if the borehole length is 15 meters at a borehole angle of 30 degrees downward, injection begins at 0 meters (with the bottom of the borehole at 0).
That said, since it’s difficult to discharge the cement slurry if the injection hose is positioned at 0 m, we raise it about 10 cm before injecting.
There are no particular issues with anchors that come with an injection hose.
If you inject from the bottom, the drilling fluid accumulated inside the casing will gush out of the top!
Most of the grout returns to the casing, but once a few casings are removed, it seeps into cracks within the borehole.
It may come loose.
If the casing comes out even when it has been inserted to the full depth of the borehole, you should consider using a packer or similar device.
Since cement slurry has a higher specific gravity than water, it can be used as a substitute for water.
Commonly known asReplacement Injectionis what they say.
Continue injecting this water until it has completely turned into cement slurry.
That completes the injection.
If you release air from the inner casing when drilling is complete to flush out the water from the borehole all at once, you’ll need less water.
The one thing you absolutely must not do is,Injecting around the mouthThat's it.
"Cement slurry has a high specific gravity, so it sinks to the bottom."
"There's no water inside the outer casing hole."
などと言うあほ職人がいますが、No way! Absolutely not!!!
If you pour it in from the top, it will definitely get diluted. Even from a physical standpoint, it will get diluted!
It's not a matter of specific gravity or anything like that.
You can't trust your gut feeling more than anything else, so please be careful!
Civil engineers work with numbers, after all, lol.
To avoid having to redo the work if it comes loose when under tension.
If it still comes loose, this indicates a problem with the design or the bonding layer, so we will need to discuss this with the client.
Let’s ensure the anchor body is properly set by carefully injecting cement slurry!!
See you later.
