Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Match Temperature curing

[Subject Prev][Subject Next][Thread Prev][Thread Next]
It's true that for mass foundation construction MTC may not be warranted however
there are instances where the cycle time is crucial in order for a section to be
loaded at a "mature" age( relatively young). Surely the curing and strength of
cubes need to be accurately determined particularly in element where a large
difference in equivalent volume/thickness between the cast section and the test
cubes exist. Question is, how do you monitor and control the temperature of the
samples to mimic temperature of the section. ?

Regards
KHOpt
CEng

Harold Sprague wrote:

> Match temperature curing is often specified for field cast concrete in which
> the temperature of the samples (cubes or cylinders) are kept at the same
> temperature as the concrete section that was cast.  Curing and strength are
> time and temperature dependent.
>
> Match temperature curing is best accomplished by covering and placing the
> samples near the concrete section that was placed.  If cold temperatures are
> anticipated, the samples should be placed under the same blanket to more
> accurately mimic the curing temperature (trapped heat of hydration) of the
> concrete section.
>
> But often, construction operations preclude this practice.  In that case the
> temperatures of the samples should be monitored and controlled to mimic the
> temperature of the section.
>
> The primary issue is curing retardation and slow strength gain due to cold
> weather.  If the temperatures are moderate and the concrete is not that
> critical (foundations), it is generally not worth the effort.
>
> Depending on the cement content, forms (insulation factor), the size and
> shape of the section (thermal mass); the thermal gradient within the section
> can vary by more than 50 degrees.  Sometimes we delude ourselves.
>
> Match temperature curing is not always accurate or necessary.
>
> Regards,
> Harold Sprague
> The Neenan Company
>
> -----Original Message-----
> From: Kho Poh Teck [mailto:ptkho(--nospam--at)pc.jaring.my]
> Sent: Sunday, September 20, 1998 4:59 AM
> To: 'seaint(--nospam--at)seaint.org'
> Subject: Match Temperature curing
>
> Can anyone let me know what is "match temperature curing" for concrete?
> I do not think it's merely having test cubes cured on site condition to
> simulate the actual element in question. If not, how would one know
> exactly the maturity of concrete .
>
> Thanks in advance
>
> KHO PT
> CEng
>
>