Hello, everyone.

This is Enta.

Spring has already arrived in the Tokai region.

But I can't go without wearing underwear under my pants (lol)

I used to make fun of them, but now I feel a bit chilly if I don't wear them.

Are you wearing underwear?

---

But that's beside the point.

Manual Drilling and Grout Injection for Self-Drilling Rock Bolts

There aren't many photos showing the drilling and grouting process for self-drilling rock bolts, are there?

So, I went out and took some photos!

We don't do this kind of work very often here either, so I figured if I missed this chance, I wouldn't be able to take any photos.

*For the retaining wall, holes are first drilled using a standard rock drill, and self-drilling bolts are then inserted into those holes.
(Drilling through a retaining wall on your own takes a long time.)

Attach a shank rod for a rock drill to the self-drilling rock bolt.

We will attach a rock drill to this shank rod.

That completes the setup, so we'll start drilling.

Since each one is 500 mm long this time, I'll keep adding more as I finish each one.

Use a coupler to top it off.

Next, I installed the shank rod and drilled the hole.

The key to drilling is to thoroughly scoop out the Kriko (drilling slime).

Doing so will ensure a clean drill hole.

Since this is intended for use in mountains where the borehole walls are not self-supporting, if the inner borehole walls continue to collapse and are discharged,

It’s actually quite common for the hole to get bigger.

Once the drilling is complete, the grouting begins.

Since there's not much this time, I'm going for a "picnic?" or "cherry blossom viewing" vibe with this setup, lol.

Since there are five bags of cement, this should be enough.

The mixer is manual, and the pump is a Peko-Pon. It's a diaphragm pump.

Yamada Corporation, Inc.

Use compressed air to force the grout through.

For self-drilling rock boltsInjection AdapterSet it up and inject it.

You cannot perform self-perforation without an injection adapter. (It’s not impossible, but it’s very difficult.)

Since the pressure is low this time, I'm using a standard air hose to fill it.

With standard grout pumps, it is dangerous to use anything other than a pressure-resistant hose.

Grout is injected through the center hole of the self-drilling rock bolt, and it is forced out from the tip and rises upward.

Since there's a bit of pressure, even if you stop it as soon as you see it, it will still rise all the way to the top.

At this point, moving the self-drilling rock bolt slightly up, down, left, and right to allow it to settle will ensure a secure bond with the grout.

In particular, if the borehole wall is not self-supporting, adhesion to the surrounding soil is a concern, so please ensure it is thoroughly compacted.

It's a small thing, but it's important, so please give it a try.

It’s fine even if I don’t let it overflow, but it just keeps coming out on its own even when I stop it (lol).

If possible, it’s best not to let it flow, as it will get dirty.

That's it.

I stuck a piece of Styrofoam in the tip, but it kept coming out from the inside due to the internal pressure, so I sealed it.

After that, fill in the gaps once it has hardened, attach the pressure plate, and you're done.

 

This is probably the first article in the world to go into this much detail about hand-drilled self-tapping rock bolts, right? lol

Please wait until the pressure plate is installed.

 

See you later.