(bright music)
- [Narrator] Rapid-setting hydraulic cement is being studied
to determine if it can be used as a solution
for structures in Texas.
This is very important
in components related to bridges and decks.
Researchers from the Texas Department of Transportation
and Texas State University perform tests
on various rapid cements,
identifying its durability and performance
to develop guidelines for implementation
on decks and bridge structures.
- So there are some specialty cements
called rapid-setting cements
that gain strength within hours,
so we're talking 3,000 PSI in three hours.
So imagine if you pour a column,
and you're waiting seven days to do something,
versus I pour it today,
tomorrow, I could strip forms and start a new process.
So the idea was how can we utilize these specialty cements
and more of the cast-in-place operations
and then bring in the precast bridge elements
to speed up the entire project as well.
- So we did both lab and field work,
and by field work, mostly what I mean by field work,
we essentially did a lot of concrete samples
that we exposed to real-world conditions,
not necessarily actual bridge structures
or going to actual job sites,
but we essentially exposed 'em outside
in the San Marcos, Texas environment.
We did a lot of tests in terms of performance,
specifically for durability,
and a lot of durability tests that are available today
that are standardized, are really intended
for the traditional Portland cement binder system.
- Some of the durability concerns were an issue.
And so through this project,
we learned that yes, that is a concern,
and so we need to be careful of where we use these
in certain applications.
And so, I think the durability, it's still new to us,
and so we need to continue learning.
And so this project really highlighted those aspects
of what we need to continue to research.
- The biggest benefit from this research
to the driving public, specifically,
is that I think we've been able to really give TxDOT
another tool in their toolbox.
So, while we still need, I think, more information,
more data to really be confident
about where these materials can be used,
there's definitely viable applications for them.
And being that they have these unique capabilities
and unique characteristics, so they have the ability
to generate strength much more quicker,
essentially turn around the construction over much faster,
and the driver, obviously, they're very happy
about when they can turn around
construction projects much faster.
- Our next step is to do some more long-term monitoring
of those durability specimens
that were fabricated during the research project.
So, they made concrete.
They'll set 'em in certain environments,
and then we'll monitor 'em and continue that work,
so we want to get, again, try to extrapolate
some longer durability, longer time periods
out this information or out those samples
so that way we can make better decisions of,
well, maybe these aren't good for a marine environment
or an area where deicing sauce will be used,
but maybe central Texas or something down in the valley
where we're not a very aggressive environment.
Maybe those would be the regions we would use these,
but some of these other locations,
we probably won't go there.
So, learning those durability performances
of these materials would help us make those decisions.
So I don't think we're quite yet on the implementation.
We still have a little bit more knowledge to gain
on some of those durability aspects.
- [Narrator] For more information
and to find the publication for this project,
please visit the TxDOT Research Library
at the link shown below.