tag:blogger.com,1999:blog-5862444008740250372.post3644908127649399859..comments2024-02-01T04:37:41.878-05:00Comments on Cap'n Transit Rides Again: The Tappan Zee Bridge is NOT structurally deficientCap'n Transithttp://www.blogger.com/profile/17057887736728828646noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-5862444008740250372.post-8513983596059545202012-09-20T17:05:19.105-04:002012-09-20T17:05:19.105-04:00Here's the link, Cap'n. I'm near a lo...Here's the link, Cap'n. I'm near a local bridge on Ashford Avenue in Ardsley that is considered Structurally Deficient. After the category, there is a number rating. I thought this list had the TZ Bridge, but now I can't find it. Must be confusing the two bridges.<br /><br />https://www.dot.ny.gov/main/bridgedata/repository/WestchesterBridgeData.pdfThe Amateur Transporterhttps://www.blogger.com/profile/11004281174306673509noreply@blogger.comtag:blogger.com,1999:blog-5862444008740250372.post-33238026103866458662012-09-19T22:16:12.777-04:002012-09-19T22:16:12.777-04:00Wouldn't it still be cheaper to move the bridg...Wouldn't it still be cheaper to move the bridge to the south or north end of the Tappan Zee? Even *with* the new roadway construction involved?<br /><br />Sigh. The bridge is in a *stupid* location.neroden@gmailhttps://www.blogger.com/profile/07475686367097445497noreply@blogger.comtag:blogger.com,1999:blog-5862444008740250372.post-77651477621585291192012-09-19T09:15:03.688-04:002012-09-19T09:15:03.688-04:00Thanks, guys! I updated the post to clarify the d...Thanks, guys! I updated the post to clarify the differences between "structurally deficient," "fracture critical" and seismically unfit.<br /><br />Alex, I'm not saying the Tappan Zee should stay, I'm saying it should be torn down. But even if it is seismically retrofitted, that would be cheaper than replacing it, and even if it's replaced, there are cheaper replacement options.<br /><br />Amateur, as I understand it, a bridge can have humungous car-sized holes all over its roadway and still not be considered structurally deficient. I don't know what the number ratings mean, but if you post a link I'll take a look.Cap'n Transithttps://www.blogger.com/profile/17057887736728828646noreply@blogger.comtag:blogger.com,1999:blog-5862444008740250372.post-18062382925293559572012-09-18T13:59:42.977-04:002012-09-18T13:59:42.977-04:00Cap'n: My head is spinning as much as the spin...Cap'n: My head is spinning as much as the spin on the pro-bridge twitter feed. Maybe we need some engineering help:<br /><br />1. What is "fracture-critical"?<br />2. How can a bridge that is not "structurally deficient" be "fracture-critical"?<br />3. There seems to be a number rating in addition to the structural deficient and functionally obsolete category. What is this?<br />4. To @AlexB's comment, what is the formula used to determine whether or not to replace a bridge based on seismic loads?<br /><br />People also tell stories about chunks of bridges falling off. Can these things (like a hole in the roadway) and still have a bridge not be structurally deficient?<br /><br />Thanks for your help on this.The Amateur Transporterhttps://www.blogger.com/profile/11004281174306673509noreply@blogger.comtag:blogger.com,1999:blog-5862444008740250372.post-31256721936387493752012-09-18T11:42:49.206-04:002012-09-18T11:42:49.206-04:00I understand that you are taking issue with the pa...I understand that you are taking issue with the particulars of word choice here and the distinction is important. That being said, whether it’s functionally obsolete or structurally deficient, neither of these things is good. I do not think it was originally designed properly for seismic (earthquake) loads. While this is not as important as if the bridge were in California, New York is seismically active and this bridge has a higher chance of structurally failing in an earthquake than a new bridge. Just because the bridge is perfectly safe to drive on during a normal day doesn’t mean we shouldn’t replace it with something safer. If Cuomo’s plan were changed and the existing Tappan Zee stays, it would have to undergo a huge retrofit that would be much more intensive than replacing the suspension cables on the GWB.AlexBhttps://www.blogger.com/profile/08641696582734014602noreply@blogger.com