Need a solid fill material between concrete and aluminum 3

[bcavender]

On a poured concrete job, there was a form problem that left a real uneven bottom to a 3’ rectangular opening. The metal to go in is already fabbed. This leaves a space that varies from nil to about 3/8”. This space is subject to long term water splashing, but not under high pressure.

The goal here is to find a material that cans stand some water movement and adhere somewhat to the concrete substrate, but holds together as a solid and doesn’t get eaten away over time.

I’m not experienced enough to say that a thin layer of plain mortar would last for a long time, especially w temp variations from -10F to 90s.

Can anyone suggest an approach or product that would be good to use in this situation?

All comments welcome!
Best regards,
B

 

[TugboatEng]

Because your gap varies to nearly 0 I recommend a 100% solids epoxy with low enough viscosity that it can be poured. 100% solids is necessary so it does not shrink as it cures or it may separate from the concrete. Epoxy products are going to average around $1 USD per cubic inch so I recommend filling as much with sand as possible before pouring the epoxy. For deep pouring with sand you're going to need to do layers. Without sand this could be done with a single pour as the space is thin and heat generation should not be a problem.

 

[bcavender]

Tug,
I like the sound of that!!!

Will research. Thank you for the assist!
B

 

[dik]

You don't want anything with a high pH in contact with the aluminum.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[bcavender]

dik,

Your quote from Coates seems more spot on every day. I was thinking that if all this mess was simply random stupidity, without malice, half of the events would be positive for people.

Anyway,

Epoxy’s ph is 12-13. I had not got around to thoughts of corrosion. With its advantages, possibly I could still use it with some nature of barrier?

Good catch, thank you!!!
B

 

[TugboatEng]

The high pH of epoxy is only temporary. The hardener is caustic. Once cured epoxy is inert.

 

[dik]

That was a quote from my son... I liked it so much, I actually paid him a stipend for permission to use it. Totally homeschooled to a Grade 13, honours English level.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[bcavender]

Dik,

My search shows epoxy fully cured in seven days. We can work that in.

Appreciate all the good assistance!!!
B

 

[dik]

Thanks Tug, it wasn't the pH of the epoxy... it was a caution in case cementitious material was used.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[dik]

@bcavender... totally off topic...

There was a recent obituary regarding someone that died in the Okanagan, BC and published by Amanda Denis, in Sudbury, Ontario. The estranged father was a miserable sod... The obit started, “I am pleased to announce...After suffering multiple strokes, one thankfully leaving him unable to speak, the abusive, narcissistic absentee father/husband/brother/son finally kicked the bucket... Because he treated people with disdain, there will be no service.” (Real obit, not a hoax). I thought it was exceptional, and sent my son a copy.

His reply, “De mortuis nil nisi bonum...but I never really believed in that saying, and the guy sounds like he was a proper bastard”, reflects his classical education.

https://www.cbc.ca/listen/live-radi...woman-pulled-punches-writing-fathers-obituary

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[EdStainless]

For many epoxy's (and other adhesives also) there are metal specific primer treatments.
There are often just a thin brush on coat to assist bonding.
Ask you adhesive supplier about the Al surface preparation requirements.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[bcavender]

Ed,
Will do.
Thanks!
B

 

[bcavender]

Dik,
My Mother (half a century ago told me, "Never ever speak the words that you can't take back."

That has served me well in the long run, but it does cause blood pressure spikes.

Your son is keeping it classy.
B