Worst Workmanship - Deficiencies - Terrible Detail (&/or interpretation) - Crazy Fixes - ETC... 2

[CELinOttawa]

In chatting on another thread, AELLC suggested this might be a fun topic. I agree.

I will get the ball rolling with the attached photo. This is meant to be a full moment, 25% shear, connection to an equal size embedded column as the base for a portal frame which supports 100% glass glazing. Warning: One cannot un-see such terrible work. Hide the kids.

 

[JAE]

Here's another one - a steel beam bearing condition that, well....could be OK. Just need to check the brick bearing.

 

[kingnero]

doesn't that beam bear on the wooden doorpost ? it must be, as those bricks have almost zero bearing strength. so it must be OK ...

 

[TehMightyEngineer]

Maybe they were planning to grout it in and forgot that step??

Maine EIT, Civil/Structural.

 

[JStephen]

A couple of stories, but short on pictures.

First off, I was out riding my bicycle a while back and went past this silo in the attached picture. That ridge about halfway up is an elephant's foot buckle, typically due to compressive loading. Either the silo was underdesigned, or not designed, or service was changed, who knows. Still in operation as far as I know.

Secondly, a story with no pictures. Quite a few years ago, a customer contacted us. They had two old molasses tanks that had been cut down, roughly 60' diameter x 40' shell height, and they wanted to rebuild those into one big flat-bottom silo roughly 60' diameter x 80' high. In theory, that part was simple enough. But, they also wanted to do all the withdrawal through a garage-door type opening at the bottom, using a front-end loader or equivalent. So I dutifully cranked out a design as best I could in the limited time available, which required a number of large stiffeners due to the eccentric loading, which also added a lot of cost to the project. To no one's surprise, we were high bidder on the job and the economy contractor down the road got the job. So several months went by and I happened to be driving down that way, and there was the silo, erected and in operation. And, up there at the top was a big ol' buckle in the shell plate. I guess as long as it didn't split down the side, they didn't care.

 

[dhengr]

JAE:
Notice that in your photo 9APR14, 13:26, there is already a black and white prestressing wire in place which must be part of their beam support system and design. They are obviously going to suspend this beam from the next level up, so the bearing area can breath.

 

[TehMightyEngineer]

dhengr: I thought to myself, "What? I don't remember seeing any strand, what is dhengr talking about [opens up picture again]-Ohhhhhhhhhh... now I get it. :

Maine EIT, Civil/Structural.

 

[dcarr82775]

Space between top of a drilled pier and bottom of a gradebeam. There were a few inches of mud and trash between them when we found them.

 

[CELinOttawa]

You're too picky Dcarr - Those rebar look like they'd have kL/r <= 200... *sarcastic smile*

 

[TLHS]

How does that last one even happen?

 

[CELinOttawa]

I've seen something similar following heavy rain on a messy site, BUT it does take talent at being slack & aweful.

 

[hokie66]

Looks like the grade beam was cast first, then the pile. The cutout in the form tube was for placing the pile concrete. The grouting never got done. A builder can think of a million ways to do it wrong.

 

[CELinOttawa]

And a gentle reminder: Once you've seen this kind of screw up, the courts have consistently found that YOU, as a Professional Engineer, are now responsible to ensure it doesn't happen again.

The "builder" as Hokie puts it is *not* at fault unless we catch them or they can be shown to disobey a specific order from an Engineer.

I've always found that completely mind-blowing and unbelievable.

 

[3DDave]

I don't have the pictures, but I'll try to paint one for you.

The state highway dept had in mind to fix a problem at an overpass, where the height was not to current Federal code. Since the overpassing road was a minor access problem, they decided to fix both at the same time. Two things had to happen - one was lowering the grade of the highway to provide more clearance, the other was replacing the overpass bridge with a wider one. If you haven't spotted the problem yet, I'll drop another hint. The highway has a slope.

Since you don't tear out a bridge after you do the nice highway, they did the overpass first. Since it was all under construction, why bother putting up new signage with the current actual measurement between the now wider-span bridge girders and the old not-yet-lowered highway surface?

The distance problem was clearly identified by a trucker who had a flatbed with a 10 foot diameter, 1/2 inch wall steel tube about 40 feet long. Given the limited amount of sideways bend in the bottom of the I-Beam it appeared that the truck went from 60mph to 0 mph over a distance of a few feet. Bad for the trucker, the load was apparently quite secure. It folded the bottom 12 inches of the I-beam about 45 degrees. I assume the load shifted a bit on the truck, but did not come loose.

Being the really smart guys they were, the bridge design had continuous I-beams cast into the concrete side walls, rather than being flanged and bolted, so there was no way to simply replace the beam. I think they just got on it with torches and beat it back into place.

Had the truck been only a few inches lower it would have cleared the final girder in the decreasing tapered distance. As I recall it was a mark only a foot wide.

I'm more negative about this particular project because it caused daily miles-long traffic back-ups every workday for almost 3 years with the goal of preventing traffic tie-ups that happened almost 5 times a year. Which still happened after the work was done.

 

[XR250]

I wonder if the project engineer got fired?

 

[ajh1]

In JAE's photo, I don't think that is prestressing wire. I think it is someone's jackleg attempt to do electrical wiring. Appears to be of the same quality as the beam support, which figures.

 

[CELinOttawa]

ajh1: It was a joke, I think...

 

[dcarr82775]

Hokie66,

Nope, the drilled pier was cast 1st, then the gradebeam. The sonotube was the repair contractor's as we were grouting the space solid after cleaning up the bars a bit more. Happened 4-5 locations that we know of on that project.

But fear not, I have the special inspector's reports that said all was well.

 

[CELinOttawa]

Lol... Love the comment about the special inspector!

I wonder if this means you can now no longer rely upon any of the inspector's reports? Anyone care to try on their "law" hat?

 

[kingnero]

Anyone care to try on their "law" hat?

whenever I see an engineer trying on his "law" hat, I run as fast as I can.
On the other side, I run as well when I see a lawyer trying on his "engineering" hat.

 

[3DDave]

A great read in repeated disaster - "To Engineer is Human"