Infrastructure: it’s all around us, and on the surface, maybe a bit mundane.
But look a bit closer and you'll see there's a fascinating world
Of ingenuity and engineering just below our noses.
I’m Grady and this is What’s that Infrastructure, where we divulge and discover the manmade
world around us.
For this first episode, I’m using some of my own photos, but my goal for this series
is to show your photos highlighting the abundance of interesting structures, systems, and utilities
that usually go unnoticed.
I’ll show how you can send in your photos at the end of the video.
Today we’re talking about transportation infrastructure, and I’ve taken some photos
of things that you might find interesting.
Here they are upfront if you want to take a guess before I say what they are.
This first one is an easy one - these are some photos I took of a sidewalk.
Notice the bumpy bricks on all of the ramps?
These are required on sidewalk ramps in the U.S. by the Americans with Disabilities Act,
but they’re not for traction like many people think.
These are called tactile paving, and their purpose is to help people with visual disabilities
delineate the boundary between sidewalk and road, detectable warnings for people who might
not otherwise be able to identify a potential hazard.
Tactile paving isn’t just found in the U.S. Lots of other countries have detectable warnings
for all kinds of hazards, including subway lines, steep grades, stairs, and of course,
road crossings.
They often have a contrasting color so they’re easy to identify, and many use a very recognizable
texture called truncated domes.
This next one is a little bit tougher.
This is a road sign I photographed while I was sitting at a red light.
Take a look at the bottom of the post.
There’s something interesting going on there.
This is a triangular slip base, one of many types of breakaway sign post systems.
In the U.S., signs located near the roadway are required to easily break away if struck
by a vehicle.
A lot of people think this is a cost saving measure, so a new sign can be easily installed
without digging a new hole.
But the real reason for the breakaway design is safety.
A well-anchored metal pole can be extremely dangerous during a high-speed car accident.
If an errant vehicle hits a sign that doesn’t break away, the narrow pole can pass through
most parts of a car like butter.
Engineers have found that it’s much safer for signs to easily break off when hit, getting
them out of the way of the accident before they can be a hazard.
This last one is something that may only be in Texas.
I’ve never seen it in another state.
This is a photo of an overpass bridge, but notice underneath the clearance height sign,
there’s some kind of galvanized bracket.
This is called a bridge protective assembly.
These are extremely common on bridges in Texas.
Their purpose is to protect the first beam from an over-height vehicle impact.
If a truck carrying something too tall tries to drive under a bridge, the impact can cause
serious problems.
Most concrete bridge beams have almost all of their reinforcing steel at the bottom.
If the reinforcement is damaged, the strength is significantly reduced.
So bridges with the highest potential to be impacted by an overheight vehicle usually
have some protection.
This bracket actually hangs from above with a layer of energy absorbing material between
it and the beam.
The goal is to reduce the vibration associated with an impact to hopefully minimize the damage
to the structure.
After a little research, I found that Texas is phasing out the bridge protective assembly
in favor a protective wrap of carbon fiber, which is apparently much more effective.
Do the bridges in your state or country have protection against over-height vehicle impacts.
Or do you have some other piece of infrastucture in your hometown that you think is unique
or interesting.
Maybe you walk by something every day and have just always wondered what it is.
I love infrastructure, and I want to show others how interesting it can be.
But, I need your help.
This series will be a lot more interesting and fun with your participation.
To share a photo with me, log on to my website at practical.engineering, click on the WTI
button, and fill out the form.
If I like your photo, I’ll send you a sticker, and I just might share it on the next episode
of What’s that Infrastructure.
Thank you for watching, and let me know what you think.