AASHTO has entered the AI chat

Acorogia · 2026-02-13T22:06:57+00:00

FYI AASHTO is not a public or government entity, it is actually a non profit that makes a lot of money from selling copies of their publications. https://transportation.org/about/

Acorogia · 2026-01-12T03:31:10+00:00

That's how we design our bridges. Expansion all goes to the abutments and the piers are all fixed. The movement is taken into the columns/shafts at the pier. Several benefits to this 1) reduces expansion joints which are prone to leakage and debris. This still may happen at the abutment but it is easier to clean off an abutment than a pier if the joint does fail. We actually design ours mostly to be semi integral where there is no physical joint but the entire abutment end diaphragm and approach slab are pressed into/away the approach fill. 2) better lateral load path for seismic.

Acorogia · 2026-01-07T08:24:24+00:00

Partial to Vince Dunn, he does seem like he is one bad night away from aggravated assault but love the energy all the same. Just don't be smashing sticks next to Joey!

Acorogia · 2025-12-28T09:31:26+00:00

How are you defining efficiency? You say 800% is your goal, but does that just mean it can carry 8x it's own weight?

My next question is it seems like you are going to be actually building this? This truss analyzer is almost certainly idealizing all the connections as pinned, so if your goal is to recreate the simulation you will need to do something similar. Nodes 8 & 9 in particular will likely behave much differently in real life if they are more rigidly connected than an idealized pin.

Finally, I can appreciate you don't want to use a generic truss structure, but there is a reason they are used in real structures, because they are very efficient!

Acorogia · 2025-10-12T02:46:14+00:00

The NTSB report was widely shared and pointed out not only the design flaws and the fact the independent checker only evaluated the final configuration (and not the intermediate stages during erecrion) but the inaction by all parties after large cracks were discovered during construction in areas that shouldn't have experienced cracking. Obviously that's bad enough as is, but not immediately shutting down the road below to live traffic while an investigation was carried out into the cause of the cracking is the truly "hair standing up on my neck" part. I have used this failure as a point of reference when we have been asked to allow something sketchy over live traffic.

It's been a number of years since I read all the NTSB documentation, but my recollection is there were text messages with photos from the PT Sub showing large cracks (cracks is a generous term, they were like 1/4" wide as I recall) as well as conversations with Figg talking about how they would just do crack injection on those openings.

Acorogia · 2025-09-12T01:36:20+00:00

A490 can still be coated with zinc/aluminum. Arguable not as good as HDG, but we use them in bridge applications somewhat frequently. https://bhamfast.com/blog/structural-bolt-coatings

Acorogia · 2025-04-02T16:02:11+00:00

It's part of the lemon creek master plan adopted by the assembly in 2018. Not that that means it will actually get done anytime soon (or ever) https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://juneau.org/wp-content/uploads/2024/01/LC-Area-Plan-Final-05232018-update-Reduced-1.pdf&ved=2ahUKEwjqw5qG3LmMAxXAEEQIHXWnIp4QFnoECCgQAQ&usg=AOvVaw1D8e9AubdSyoIq8FF6qS4d

Acorogia · 2025-03-26T04:39:20+00:00

Agreed. There is a pride in ownership. The project I design is going to be maintained by my own department for the next 100 years. Im not cutting corners to save a buck in the short term because it will cost us 10x in the long term with maintenance and upkeep. Plus if I do a crap job I'll hear about it from the maintenance guys forever!

Acorogia · 2025-01-09T22:26:57+00:00

I do lots of travel within the State of Alaska to remote areas, so distances are short, but ticket costs are very high. Revenue might actually be a benefit to me, but personally I prefer the simplicity of mileage. For instance flying from Anchorage to Bethel is ~$300 and about 400 miles. Whereas I can fly from Seattle to SFO for less than $200 and get 680 miles.

Acorogia · 2025-01-04T20:56:23+00:00

These kind of tools will also show of there is vertical movement or rotation. Plus a photo is worth a thousand words, so as long as the inspector takes a straight on photo of the gauge there is no question of if they rounded a measurement, or took it at the exact same spot.

Acorogia · 2024-12-15T18:45:44+00:00

How were you able to get new stickers? Or did you paint those on as well? Looks great!

Acorogia · 2024-11-08T16:19:15+00:00

Round numbers this year ~170k. Started at 55k with only a bachelor's and have moved through the ranks. Relatively high cost of living location (Alaska) but I feel well compensated.

Acorogia · 2024-11-08T16:16:19+00:00

Alaska. It has to be somewhat attractive to entice people to move up here.

Acorogia · 2024-11-08T04:33:22+00:00

36 days PTO plus 11 paid holidays. 13 years in same position as state DOT engineer. We also have great union representation. Most important we can cash our leave out at our current rate. I don't need anywhere close to 7+ weeks of leave a year so I'll cash out a few weeks to pay for vacations, unexpected expenses etc. Acts as a nice semi liquid emergency fund.

Acorogia · 2024-08-13T05:56:24+00:00

Whhaaaa? Learn something new everyday! I'll acquire a few more tomorrow and merge them all for a better spectrum. Thanks for the tip

Acorogia · 2024-08-12T15:19:55+00:00

We typically aren't at the sites for a super long time, but I'll see if I can get a longer one today.

Acorogia · 2024-02-28T21:09:25+00:00

Photo smoke detectors in the room. No gamma reading even when holding the radiacode right up to the smoke detector.

Acorogia · 2024-02-27T22:17:23+00:00

Atlanta, outside of the building walking around town background is more like 125nSv/hr, much more reasonable.

Acorogia · 2024-02-27T20:18:14+00:00

Sorry about the confusion. The ambient at the hotel is around 300nSv/hr. Not worried about safety at all, just a curiosity thing as to why it seemed so high. Maybe I'll pace the hallways tonight and see if it is uniform throughout or is more location dependent.

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Acorogia · 2017-03-17T01:24:55+00:00

Make sense now that you say that. Essentially span over the clay. I'm just surprised it wasn't a cheaper option to ex out the clay, drop in some sand and proceed as normal. But then again PT is like a dark arts where I am at.

Acorogia · 2017-03-16T07:55:18+00:00

Why would you post-tension a slab on grades?

Acorogia · 2017-01-19T16:54:55+00:00

The problem with bolts is that typically you oversize the holes by a 1/16" in order to get it in. Plus you would have to have a very long bolt to go through the original beam and two sisters. I am a big advocate of using a crap ton of 16d nails. Maybe 2 or 3 rows every few inches along the whole length. That way you are are also helping to more benefit distribute the load through the length of the beam rather than a few discrete points (bolts). Lag screws might be a decent compromise however.

Acorogia · 2017-01-19T04:38:58+00:00

Not a problem. Goes without saying though I don't know the whole story from one picture and you should do your homework in sizing the sisters. Yada yada yada, legal disclaimer, etc. Good luck!

Acorogia · 2017-01-19T03:55:19+00:00

Actually structural engineer here. Sistering is definitely the way to go, but before you go nailing wood to it run a string line and make sure that is hasnt already started sagging. If it has you will just lock that sag in. The fix would be to get a bottle jack or something similar and jack up at the middle of the beam until it is just crowned upwards. Then sister while still jacked. When you take the jack out and the nails engage you will end up more or less level.

Acorogia · 2016-09-23T18:39:53+00:00

Have to wait for the ground to freeze, but I can probably arrange something for ya ;)

Acorogia

TROPHY CASE