Here in Georgia, sometimes the bridge rails will have the year the bridge was built engraved in the concrete.
https://www.google.com/maps/@33.9653001,-84.2647152,3a,75y,326.04h,73.62t/data=!3m6!1e1!3m4!1sSGOx1YmSdj-rCF2L0NWLkw!2e0!7i16384!8i8192?entry=ttu (https://www.google.com/maps/@33.9653001,-84.2647152,3a,75y,326.04h,73.62t/data=!3m6!1e1!3m4!1sSGOx1YmSdj-rCF2L0NWLkw!2e0!7i16384!8i8192?entry=ttu)
I've been using the satellite archives to date bridges from historical aerials. But I like to guess their build date when I first see them without looking.
It seems that bridges that have the greenish tints on their girders were built in the late 70s/early 80s
https://www.google.com/maps/@33.7644197,-84.4930203,3a,75y,18.47h,96.54t/data=!3m7!1e1!3m5!1sSpYtniw7gn_lUiwGTh6vmg!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DSpYtniw7gn_lUiwGTh6vmg%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D318.40076%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?entry=ttu (https://www.google.com/maps/@33.7644197,-84.4930203,3a,75y,18.47h,96.54t/data=!3m7!1e1!3m5!1sSpYtniw7gn_lUiwGTh6vmg!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DSpYtniw7gn_lUiwGTh6vmg%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D318.40076%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?entry=ttu)
Bridges that have piped railing are usually (not always) early 1970s and earlier.
https://www.google.com/maps/@33.5572336,-84.592127,3a,75y,28.92h,93.7t/data=!3m7!1e1!3m5!1sNpTHfnldjncBVSw7k8JwZA!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DNpTHfnldjncBVSw7k8JwZA%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D88.16121%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?entry=ttu (https://www.google.com/maps/@33.5572336,-84.592127,3a,75y,28.92h,93.7t/data=!3m7!1e1!3m5!1sNpTHfnldjncBVSw7k8JwZA!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DNpTHfnldjncBVSw7k8JwZA%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D88.16121%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?entry=ttu)
What are some giveaway characteristics that you can spot on a bridge and tell automatically when it was built?
South Carolina has also done this consistently with their bridge parapets since at least the 1930's, and I've noticed this a few times in Alabama as well but it's not consistent. If you travel the circa mid-80's constructed section of I-65 north of Birmingham, specifically around Kimberly and Morris, the bridge parapets will have one year on the right side (either 1986 or 1987) and a different year on the left side when it was widened to six lanes (can't remember if it was late 90's or early 00's).
Quote from: Georgia Guardrail on December 11, 2023, 07:29:12 PM
Dating a Bridge
Compliments and flowers are always nice.
If we're talking about the year the bridge was built written somewhere, Timnath has one (https://www.google.com/maps/@40.523121,-104.9867052,3a,24.7y,333.11h,91.63t/data=!3m6!1e1!3m4!1sTB7eqwZ3lGy8VH86S8OQSA!2e0!7i16384!8i8192?entry=ttu).
Is it a bridge with benefits? :hmm: :hmm:
Have you tried Bridges Only?
Last time I dated a bridge, I walked out on her.
I dated a bridge named Galloping Gertie once, but God that was such a wild ride I had to bail on her.
I had a fling with this bridge (https://img-aws.ehowcdn.com/700x/www.onlyinyourstate.com/wp-content/uploads/2018/11/4088200850_5ee9a1007a_b.jpg) in my younger SC days but had to break it off...she was a bit of a swinger and opened herself up to far more people than me and it was causing truss issues.
Check out the size of these DDs.
https://maps.app.goo.gl/9Yg1BfngNFUPVzyg6
https://maps.app.goo.gl/DBKVBcFC5w427iUS7
https://maps.app.goo.gl/mqrTfYMvKzqQesmp6
I could ride them All. Day. Long.
I went out to dinner with the VA-230 Conway River Bridge. She was quite scenic. My next date with her should go better.
I tried to date a bridge. She wasn't confrontational because she literally took the high road over everything in her way.
I tried to, but she had truss issues.
Once you get over the pier pressure, asking a bridge on a date is easy.
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
I was told that I needed to be less rigid if I wanted things to last.
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Quote from: Max Rockatansky on December 13, 2023, 08:46:54 AM
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Would she give you a suspension?
Quote from: Big John on December 13, 2023, 08:55:11 AM
Quote from: Max Rockatansky on December 13, 2023, 08:46:54 AM
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Would she give you a suspension?
Probably worse, she certainly isn't a swing span.
Quote from: Max Rockatansky on December 13, 2023, 09:19:45 AM
Quote from: Big John on December 13, 2023, 08:55:11 AM
Quote from: Max Rockatansky on December 13, 2023, 08:46:54 AM
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Would she give you a suspension?
Probably worse, she certainly isn't a swing span.
When my lovely bridge found out I'd paid a toll elsewhere, she became cross and decked me.
Quote from: formulanone on December 13, 2023, 09:35:32 AM
Quote from: Max Rockatansky on December 13, 2023, 09:19:45 AM
Quote from: Big John on December 13, 2023, 08:55:11 AM
Quote from: Max Rockatansky on December 13, 2023, 08:46:54 AM
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Would she give you a suspension?
Probably worse, she certainly isn't a swing span.
When my lovely bridge found out I'd paid a toll elsewhere, she became cross and decked me.
Would she be willing to have a three span?
Quote from: jeffandnicole on December 13, 2023, 09:54:18 AM
Quote from: formulanone on December 13, 2023, 09:35:32 AM
Quote from: Max Rockatansky on December 13, 2023, 09:19:45 AM
Quote from: Big John on December 13, 2023, 08:55:11 AM
Quote from: Max Rockatansky on December 13, 2023, 08:46:54 AM
Quote from: Great Lakes Roads on December 13, 2023, 02:16:16 AM
Quote from: Big John on December 12, 2023, 09:38:04 PM
Quote from: formulanone on December 12, 2023, 09:23:25 PM
Once you get over the pier pressure, asking a bridge on a date is easy.
I was told to get bent.
And I was told to pay a toll... :-D
When I'm out of town sometimes I pay for a bridge. My wife would probably be angry if she ever found out.
Would she give you a suspension?
Probably worse, she certainly isn't a swing span.
When my lovely bridge found out I'd paid a toll elsewhere, she became cross and decked me.
Would she be willing to have a three span?
Nope, cantilever.
I prefer camelback but, for the sake of my wooden kingpost, its application is limited to short spans.
Quote from: kphoger on December 14, 2023, 01:08:46 PM
I prefer camelback but, for the sake of my wooden kingpost, its application is limited to short spans.
Nobody wants to hear about your cocker spandrel.
Don't talk about your unit.
Quote from: Big John on December 14, 2023, 05:22:03 PM
Don't talk about your unit.
As discussed in the Metrication thread, smaller units can be more useful.
Quote from: kphoger on December 15, 2023, 10:44:25 AM
Quote from: Big John on December 14, 2023, 05:22:03 PM
Don't talk about your unit.
As discussed in the Metrication thread, smaller units can be more useful.
It's not the size of the unit that counts, it's how you use it.
Quote from: Max Rockatansky on December 15, 2023, 11:22:38 AM
It's not the size of the unit that counts, it's how you use it.
Wait, are we talking about something other than decimals now?
Quote from: kphoger on December 15, 2023, 11:39:22 AM
Quote from: Max Rockatansky on December 15, 2023, 11:22:38 AM
It's not the size of the unit that counts, it's how you use it.
Wait, are we talking about something other than decimals now?
The Arch.
Quote from: wriddle082 on December 11, 2023, 08:00:48 PM
South Carolina has also done this consistently with their bridge parapets since at least the 1930's, and I've noticed this a few times in Alabama as well but it's not consistent. If you travel the circa mid-80's constructed section of I-65 north of Birmingham, specifically around Kimberly and Morris, the bridge parapets will have one year on the right side (either 1986 or 1987) and a different year on the left side when it was widened to six lanes (can't remember if it was late 90's or early 00's).
Getting slightly back on (the intended) topic, I think ALDOT started casting the dates into the railings of their bridges in the 1970s, when they switched to Jersey-style barriers, as the earliest I've seen a year was from sometime in the 70s in the rural parts of eastern Colbert County, I'd have to go find it again.
The older bridges (with the older styles of railings) don't seem to have typically featured the years on them. Some old railroad overpasses did, however.
EDIT: Here's the bridge I was thinking about. (https://www.google.com/maps/@34.769368,-87.4180091,3a,75y,252.95h,73.74t/data=!3m6!1e1!3m4!1s75EYnoF6xg38C5_PDCSQuA!2e0!7i16384!8i8192?entry=ttu) You can see the 1979 year cast onto the railing.
Quote from: Georgia Guardrail on December 11, 2023, 07:29:12 PM
What are some giveaway characteristics that you can spot on a bridge and tell automatically when it was built?
I'm not well-traveled enough to say it definitively, but I think Georgia's one of the easiest states for what you're talking about, at least in the pre-Jersey barrier era. Distinctive guardrails are the main reason-- there's the move away from concrete stringers to steel, but that's a redundant factor.
Arkansas typically puts mini-plaques on the railing heads of bridges. I've seen them stamped into the Jersey rail of Louisiana bridges. But Texas is hit or miss.
NJ has been doing it since the 30s. They also used to imprint the highway number on the opposite side, which now means a much of bridges have mismatched numbers. https://maps.app.goo.gl/QMMx24nPCRVZet4D8
Bridges built in the 60s and 70s I'm pretty sure used poor quality concrete for the dates so now wherever the date is supposed to be there's just a hole. Can't find any now on gsv but they exist.
Now they imprint the date into jersey barrier.
https://maps.app.goo.gl/q2SBBSxC8VnGkc9y6
I've actually seen them put future years on bridges, like 2024 on a bridge in 2023