[TowerTalk] Concrete with air.

[J.G.Castellano]

Thanks Kelly and Hank for your replies.

73,
Julio VE3FH

----- Original Message ----- 
From: kr7x at comcast.net
To: J.G.Castellano ; towertalk at contesting.com
Sent: Wed, Oct 10, 2007 11:18
Subject: Re: [TowerTalk] Concrete with air.


Julio:

What they are suggesting is higher strength concrete 25Mpa which is about
3600 psi. The air is air entrainment. 5% is the value you should look for.
This will improve the conrete's durability especially freeze-thaw
durability. I know you VE3's live in the temperate zone but every little bit
helps. Mpa is the abbreviation for Mega-Pascals the metric measure of
pressure or in this case force per unit area.

Regards
Lonberg Design Group, Ltd.
H. Lonberg, P.E., S.E., PEng.
President

-------------- Original message -------------- 
From: "J.G.Castellano" <caste at sympatico.ca>

> Hello,
>
> I am installing a Trylon tower and the foundation drawing calls for
3,000PSI
> concrete (20MPa), when I explained what I was doing one of the concrete
> companies recommended 25Mpa with air. Can someone please explain what is
the
> difference.
>
> 73,
> Julio VE3FH
>