{"id":4476,"date":"2017-09-12T08:00:30","date_gmt":"2017-09-11T23:00:30","guid":{"rendered":"https:\/\/norimen.net\/wordpress\/?p=4476"},"modified":"2026-05-17T06:39:04","modified_gmt":"2026-05-16T21:39:04","slug":"introduction-to-ground-anchor-head-treatment","status":"publish","type":"post","link":"https:\/\/norimen.net\/en\/ground-anchor-head-treatment-intro\/","title":{"rendered":"Head Treatment for Ground Anchor Construction"},"content":{"rendered":"

Hello, everyone.<\/p>\n

This is Enta.<\/p>\n

Today I took a little trip out of town and came to Yamanashi.<\/p>\n

It's been a while since I've been to Yamanashi.<\/p>\n

It reminds me of a time long ago when we used the large-diameter all-casing method (Benoto piles) in \u014ctsuki City, Yamanashi Prefecture.<\/p>\n

\"\"<\/p>\n

Back then, I was stuck at the emergency response site for the Chuetsu-Oki Earthquake in Niigata Prefecture for about eight months, andI've gained a strange sense of confidence.<\/strong><\/span>That's right.<\/p>\n

During the day, I oversee the installation of anchor bolts while simultaneously supervising the sprayed mortar work next to me and managing the formwork above.<\/p>\n

It was quite a feat to install rock bolts on the sprayed mortar surface from evening until late at night, wasn't it? lol<\/p>\n

I suppose this is what people commonly refer to as a \u201cblack company,\u201d but back then, everyone around me was working just as hard under the same conditions.<\/p>\n

In short, the people working to open up isolated roads, those working to prevent further collapse of the damaged slopes, and the earthwork crews.<\/p>\n

Everyone was working together, wasn't it? Haha<\/p>\n

My first trip to Yamanashi Prefecture was right after I finished some emergency construction work.<\/p>\n

I remember it well\u2014spending a leisurely time there at Benoto-bashira, in a prefecture I was visiting for the first time.<\/p>\n

When I think of Yamanashi, I picture a laid-back atmosphere. (laughs)<\/p>\n

So, the thing that really surprised me was Koma District! Kyo-ma? Gun?<\/p>\n

\"Wow, that's one crazy name!!\"<\/p>\n

But it's the same name as the main character in that \"Bari Bari\" legend. Haha.<\/p>\n

\"\"<\/p>\n

That really brings back memories, lol.<\/p>\n

\n

But that's beside the point.<\/p>\n

 <\/p>\n

The Key to Head Processing<\/h3>\n

During the second half of the ground anchor installer certification renewal training held the other day, regarding the method for treating the head...<\/p>\n

There was one thing I was told to make sure I did properly.<\/p>\n

I didn't know that either.<\/p>\n

\"\"<\/p>\n

Place materials such as waterproofing compounds, expanding agents, or foam rubber and polyurethane foam\u2014which act as rust inhibitors\u2014behind the anchor head.<\/p>\n

\"\"<\/p>\n

I applied rust-preventive oil to the head cap.<\/p>\n

\"\"<\/p>\n

I closed the cap.<\/p>\n

That won't do!<\/strong><\/span><\/p>\n

The problem is that the rust-preventive oil apparently doesn't adhere well to the anchor head, wedges, or PC steel strands.<\/p>\n

\"\"<\/p>\n

If it doesn't bond properly, it will rust in a few years, which makes it extremely dangerous.<\/p>\n

So,You need to make sure to color in the area indicated by the arrow thoroughly.<\/span><\/strong><\/span>That's right.<\/p>\n

Apparently, even in the worst-case scenario\u2014if there\u2019s no rust-preventative oil in the head cap\u2014as long as the head itself is thoroughly coated, the anchor head won\u2019t rust.
\n(Please make sure to fill the cap all the way, too.)<\/p>\n

It turns out that just a little thoughtfulness is the key to making things work in the long run.<\/p>\n

Things You Must Never Do When Treating the Head<\/h3>\n

This actually surprised me, too, but,<\/p>\n

If the anchor is not treated at the head on the same day after it has been tensioned and set,<\/span><\/strong><\/span><\/p>\n

There are contractors who handle all the head-related work in one go at the end.<\/span><\/strong><\/span>That's right.<\/p>\n

This, at least,Things You Must Not Do<\/span><\/strong><\/span>That's it.<\/p>\n

It is an absolute prerequisite that head treatment be performed on the same day as the tension procedure.<\/p>\n

That's because it's guaranteed to rust within a few hours.<\/p>\n

The material used for anchor heads and the like is commonly referred to as \"raw material\"; it is simply cut-out iron in its natural state.<\/p>\n

Oxidation begins immediately upon contact with oxygen.<\/p>\n

If you don't have time and absolutely have to come back another day, just apply some grease before you leave, and you'll be fine.<\/p>\n

However, if there is a risk of rain, you'll need to wrap it in plastic sheeting or tape.<\/p>\n

That just goes to show how important it is to protect anchor heads from rust.<\/p>\n

\"\"<\/p>\n

This kind of thing is absolutely unacceptable.<\/p>\n

At this point, you'll need to scrub it with a wire brush.<\/p>\n

However, it's already too late, and applying rust-preventative oil on top of this won't stop the rust from spreading.<\/p>\n

Please be very careful.<\/span><\/strong><\/span><\/p>\n

 <\/p>\n

See you later.<\/p>\n

I can't stress this enough: This is how you handle the head of a ground anchor!<\/a><\/p><\/blockquote>\n