Here are a couple of surviving OV-20s from the original construction of this Boston freeway, or expressway or interstate or wherever it is called out here rather than in California lol. This is northbound I-93 just south of downtown Boston. Just after these OV-20s is the tunnel portion of I-93 that was built in the Big Dig project. I remember the old elevated road with OV-20s and Form 109s before the tunnel was built.
WOW!!! Ehh i typically call it either an interstate or the highway. I know Joe Maurath will be happy to hear there're still some left from before the Big Dig! Personally i don't know why they would want to build a tunnel under a river. It's just common sense to build a bridge.
Mike, we have the widest tunnel in the world in Baltimore MD. See here
It is not ALWAYS the best to just build a bridge.....sometimes it's better to do underground.....I think underground actually lasts longer.... Gallopin' Gertie plus nobody can jump out of a tunnel to kill themselves!
That bridge was obviously constructed very poorly. The big dig has had quite a few issues. It's probably spent more than half of it's life getting repairs. It's just more cost effective to build a bridge. We have many bridges here from the 50s that are still in okay condition.
And what if the tunnel caves in? that's worse than simply one person jumping off a bridge! On top of that, if a person wants to jump off a bridge, let them, but a tunnel caving in and washing out hundereds of people who didn't want to die would be way worse and that should not happen.
IMO, having tunnels that go under water is just a thing the state does for attention and something that the state does to brag about and nothing more.
Ahh Gallopin' Gertie IIRC it fell because the wind caused it to resonate at its natural frequency which caused it to break apart. TL/DR it had a design flaw.
Tunnels are usually used where a bridge would take up too much space, look ugly, or would block stuff like in a harbour or a canal for example. So it really depends on the situation whether a tunnel or bridge is better.
Yes, also bridges can collapse too......So Joe is really right about it....tunnels do have functions, Fort McHenry Tunnel has a lot of boats around the area so it is easier to have a tunnel.
Yep tunnels will work fine underwater if properly designed. The Big Dig project was just poorly engineered. Another issue is that several of the fluorescent lights rusted out and fell onto the pavement. The manufacturer of these fixtures no longer exists and the state DOT is unable to claim damages against that manufacturer. So many issues.
Joe, Fort McHenry Tunnel in Baltimore, dubbed the World Widest Tunnel, still has the fluroescent and installed in early to mid 80s!!!! Although there is a very very short section of test LEDs which are really dimming fast and been testing for 3 years so it looks like no LEDs anytime soon anyway.......
The older Tunnel the Harbor Tunnel used to have LPS but was recently changed with Icetrons, I think the same fixtures though!
I assume these have transformer bases for the ballasts right? I've never seen a transformer base in RI. It seems the remote ballasts were attatched to the side of the pole with a steel mounting plate. The poles on Rte 2 that Dave uploaded a week ago have the rusty plates on the pole so that it faces traffic when the pole is on the left side of the road.
Transformer bases are rare in Ontario too, I've only ever seen them in a few places, mostly parking lot lighting and those merc posttops in Niagara Falls. Most remote ballasts here were attached to the side of the pole, in fact some poles here still have their ballast cans.
Yes they have transformer bases, it seems many poles in MA have them. According to recent correspondence with Joe Maurath, nope these OV-20s don't work.
I only saw these two. I think there might be more of these old poles along the ramps on the I-90 Mass Turnpike but they now have LPS. I'm still surprised these poles are still standing. These OV-20 poles have rust running down the poles/transformer bases down onto the concrete foundations.
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It is not ALWAYS the best to just build a bridge.....sometimes it's better to do underground.....I think underground actually lasts longer.... Gallopin' Gertie plus nobody can jump out of a tunnel to kill themselves!
And what if the tunnel caves in? that's worse than simply one person jumping off a bridge! On top of that, if a person wants to jump off a bridge, let them, but a tunnel caving in and washing out hundereds of people who didn't want to die would be way worse and that should not happen.
IMO, having tunnels that go under water is just a thing the state does for attention and something that the state does to brag about and nothing more.
Tunnels are usually used where a bridge would take up too much space, look ugly, or would block stuff like in a harbour or a canal for example. So it really depends on the situation whether a tunnel or bridge is better.
The older Tunnel the Harbor Tunnel used to have LPS but was recently changed with Icetrons, I think the same fixtures though!