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RE: Cement Certifications/C1157

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Bill,

We have specified C1157 on a few projects.  It is new.  What I meant by more
options is that you can specify low heat or moderate heat along with
moderate sulfate resistance or high early or any combination.  The lack of
restrictions allows a practice that already happens.  In order to get better
sulfate resistance and to lower the heat of hydration, companies have been
grinding ash with the portland.  It is not a true ASTM C150 when they do
that, but the cement performs better.

I am not too troubled by Section 1.5.  It does not say the "engineer" is
responsible.  It states that the "user of this standard" is responsible for
... safety and health...  It is just an attempt to shield the ASTM.  By the
specifier requiring the "user" to be responsible the user then becomes the
contractor, ready mix supplier, or whomever uses the ASTM specification.

The ready mix people aren't too thrilled with the idea of more storage bins,
but the cement suppliers like the additional latitude for larger projects.
I also like the additional latitude.

Regards,
Harold Sprague


> -----Original Message-----
> From:	Sherman, William [SMTP:ShermanWC(--nospam--at)cdm.com]
> Sent:	Friday, October 13, 2000 8:49 AM
> To:	'seaint(--nospam--at)seaint.org'
> Subject:	RE: Cement Certifications/C1157
> 
> Harold Sprague wrote:
> 
> > The best option is to drop the C150 all together and switch 
> > to the C1157 specification and performance specify the cement.  There
> are 
> > a lot more options in the C1157 as opposed to the C150.  You can fine 
> > tune the heat of hydration performance aspect.
> 
> Harold, I have only recently become familiar with the C1157 standard and I
> am 
> confused with how it offers "a lot more options" than C150. Regarding heat
> of 
> hydration, both specs seem to have similar limits for low or moderate heat
> of 
> hydration cements. I don't see many more options for the engineer just
> more 
> options for the supplier, since C1157 states "there are no restrictions on
> the 
> composition of the cement or its constituents". 
> 
> Have you or other engineers on the listserver specified this cement yet?
> While 
> "performance standards" make sense for some things, I have trouble with
> the
> idea 
> of not having any restrictions on composition of a product with such a
> long
> history 
> of use and development. This standard also places responsibility on the
> engineer for 
> "safety and health practices" and "regulatory limitations" when using this
> cement.
> It would seem the engineer is buying into a lot of liability.
> 
> Frankly, I find this standard just plain "scary".  
>