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- [Voiceover] As traffic volumes increase everywhere
in Texas as the state's population increases,
TxDOT wants to determine
if innovative intersection alternatives are safer
than typical intersections.
To develop design guidance for TxDOT,
researchers with the Texas A&M Transportation Institute
have conducted an analysis
to determine the operational and safety benefits
of various intersection designs, including roundabouts.
- A roundabout as a circular intersection,
and they've been used nationwide and even worldwide,
but largely in urban and suburban locations
where speeds are already somewhat lower.
There is less known about how they operate
in rural locations with high speed approaches.
- I think it was important for this research specifically
to kind of quantify some of the really,
kind of the unknowns
that we've had when it comes to innovative intersections.
So, innovative intersections is a term that's been around
for a while and it covers a wide range
of nonstandard intersection designs,
where the goal has been to reduce the conflict points
and to reduce the severity of crashes that occur
at a typical four leg crossing intersection.
- There's another kind of broad category
of intersections called innovative intersections
or maybe alternative intersections.
We looked at different forms of those intersections.
One thing that they have in common is
that their design characteristics are tending
to accommodate left turn traffic
in different ways than a traditional intersection does.
And so again, those are being used
in a number of different locations around the country,
but they're not as commonly found in Texas.
And so TxDOT was interested
in ways that those might be used here
and how would we go about doing that?
- The researchers went to two sites
for roundabout data collection and then another two
or three sites, I believe, for the U-Turn data collection.
And then they looked at crash history of existing locations.
So, they pulled other state DOTs.
They found locations across the, you know,
the country that had been in place for
at least five or six years or more.
And so you're able to look
at the before and after crash data.
- We actually collected data
at these types of intersections,
both within Texas as well as outside of Texas.
With the field data that we collected,
we used that to develop micro simulation scenarios.
And then we tested a lot of additional scenarios
that don't exist in reality,
but a way to determine how to change different
design characteristics to see what works best.
Through our work, we have identified
that roundabouts in rural and rural locations
with high speed approaches can work in Texas.
The data indicate that they will perform properly
if they're designed to meet those conditions.
On the innovative intersection side,
they will work in Texas.
We're able to provide some guidelines for them to be used.
- This project makes Texas roads safer.
We have to apply the principles that we've kind of outlined
in the guidelines that the research has put together,
but ultimately, this project makes Texas roads safer.
- For more information
and to find the publications for this project,
please visit the TxDOT research library
at the link shown below.