Hello, everyone.

This is Enta.

Do you use Cantab?

Cantab

This product makes it easy to measure the chloride content in fresh concrete and fine aggregates.

The chloride ion concentration in concrete is generally considered to be 0.3 kg/m³ or less.

In short, if the concentration is any higher, the rebar in the concrete will corrode and expand,

This means that cracks may form in the concrete, and in the worst-case scenario, there is a possibility of structural collapse or mortar spalling.

Alkali-Aggregate Reaction It's a little different from (wiki).

For on-site spray-applied formwork, monitoring chloride levels on-site is a mandatory requirement.

At NEXCO and other organizations, grout and similar materials are also included in this category.

Measurement Method

So, how is this measured? Generally speaking,A product called Cantab We use it to take measurements, but

At first glance, this measurement method might be difficult for a layperson to understand.

That said, the measurement instructions are actually printed inside the Kantab box lol

First, prepare the test specimen (for the core). Next to it, stick the Cantab into the leftover mortar.
(As long as the mortar is to be used on-site, any method of procurement is acceptable.)

If you insert and remove it a few times, the moisture from the mortar will come out, and if you let it collect on the cotton wool at the bottom of the Cantab, it’ll be done faster lol.

Do not pour water into it from above at this time.

I can't get an accurate value.

↑ This is right after I stuck it in. This is what it looks like when I take it out of the aluminum bag.

If you leave it for about 10 minutes, the moisture will be drawn up to the top, andInk is leaking from the top side...Once it arrives, it's over.

Post-Measurement Processing

1. Be sure to thoroughly remove any ink and excess moisture.
　If you press down hard on the cotton pad with your fingernail, water will come out.

2. Please write the numbers 1 through 3 on the back of the Cantab. (It's okay to write them first.)

3. Please write the reading on the back of the form right there.
(The results will change slightly over time due to the remaining water. I know, lol.)
　When taking a photo, just record the values as they are at that moment; even if the results change over time, the photo will still be there, so it’s not a problem.
　The data from that time is important. (Since Cantab sometimes disappears before you know it.)
　For public corporations such as NEXCO, photography is always required at that time.

4. Please write the date on the original aluminum bag and store it there.

 

For now, that wraps up the Cantab measurements on site.

After that, I'll head home and get to work organizing my paperwork.

Cantab (Salinity Test) Low Concentration (12 packs of 3 test strips each)

Since the amount of spray-applied material used depends somewhat on the type of sand, I think it would be best to use high-quality river sand if possible.

As long as it's not sea sand, I don't think you need to worry too much about the salt content.

However, since there’s plenty of high-quality sea sand available these days, I don’t think it’s something to worry about.

By the way,Kantab is a low-concentration productSince we are using it,

If you can get a reading on the Cantab using a low-concentration solution, the salt content will definitely not exceed the limit.

If the reading is outside the measurement range (exceeds the reading for the cotton pad), it is considered a standard sample.

 

See you later.

A Few Tips for Measuring Salt Content