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Structural Abuse

Structural Abuse

Structural Abuse

(OP)
Just thought this was an interesting topic.

When have you seen the builder effectively violate the structural integrity of your design because of a clash with services e.t.c.

Here is a good (meaning bad) example:

http://www.dbp.org.uk/cs/DBP00042.pdf

RE: Structural Abuse

I saw something just like that once in, of all places, San Francisco.  A cross brace in a building was cut through (completely) to accommodate a pipe.  Built in the 1950's the building apparently stood fine through numerous seismic events until late 1990's when we discovered it.

 

RE: Structural Abuse

Just like it writes:
"Never over estimate people inteligence - some people are stupid"

RE: Structural Abuse

Obviously the guy who cut it knew he was doing.  The structure is still standing smile.  That is crazy.

Never, but never question engineer's judgement

RE: Structural Abuse

Over the years, we have encountered some pretty silly things:

Cutting out of the webs of a bar joist to pass ductwork thru it.

Cutting of a beam to run ductwork and then replacing the beam with jogging the beam around the ductwork in plan (one continuous beam... like a crankshaft in plan)

Removal of bracing

RE: Structural Abuse

Thats just plain stupidity !

The guy who did that should be sacked immediately!

RE: Structural Abuse

Hey, some perfectly qualified engineer might have spent hours analyzing that beam and discerned that it COULD be cut like that without a loss of integrity.

RE: Structural Abuse

JStephen-

That's a column (sic) not a beam :)

RE: Structural Abuse

I doubt that very much !

RE: Structural Abuse

(OP)
Anyone else have some good examples? Some good ones regarding cantilevers are mentioned in the aisc site fixes lecture.

RE: Structural Abuse

Those are the kind of thing resident consultant engineers, or any one assigned to supervise the structures during construction or when any adjustment to buildings are done need to look at.

Let us engineers open our eyes and see beyond beyond that!

 

Practicing engineering is hard than studying it!!!

RE: Structural Abuse

(OP)
Godfrey,

For sure! Our lecturers used to say to us that we will only learn 10% of what we need to know at university the rest on the job. I agree with them.

You never stop learning.

RE: Structural Abuse

"That's a column (sic) not a beam :) "

You are correct.  Referring to the 9th AISC, I should have said "member" or "element" or "shape" rather than beam.  I find "American Standard  beams" used and find "Stuctural tees are obtained by splitting the webs of various beams" and a mention of "beam webs" but otherwise don't see the word used in a general sense.

RE: Structural Abuse

That is not a column nor a beam!!  It is a valve protector!

Never, but never question engineer's judgement

RE: Structural Abuse

I've seen MANY of these (including the one the OP highlighted) and they always drive me nuts.

Here's a picture taken by a co-worker, Matt Hamilton, on a jobsite visit a few months back.  I love the fact that this pipe had to go precisely where there happened to be a gap in the web doubler plates - the absolute weakest section of the column.



If you "heard" it on the internet, it's guilty until proven innocent. - DCS

RE: Structural Abuse

swearingen - looks like its been there a while with all that rust.

 

RE: Structural Abuse

At least they left the flange in position on that one.

RE: Structural Abuse

(OP)
At least that second one may have kept 40% of the original capacity, rather than about 4% for the first one!

RE: Structural Abuse

Here's an experience I had:

The owner of a new 5 story high end residential building was issued a stop order for failing to collect construction trash in a dumpster  every day.

When additional inspectors came to the site with copies of the approved plans, they realized that the structural system that was approved by the Structural Bureau, was not what was actually built. The contractor thought that it was OK to replace precast concrete planks bearing on masonry walls, with a steel frame, beams and columns and cip concrete slab that he sized and built according to "his experience". A lot of scary detailing was also found.

RE: Structural Abuse

That contractor should have been jailed.

RE: Structural Abuse

A long time ago I had an architect ask if they could cut a 22" hole in a 20" deep concrete beam.  Honest to God he did!

RE: Structural Abuse

(OP)
classic luvit!

RE: Structural Abuse

I once heard from a guy who sold insurance about a claim he went on. It seems that when some guys in a garage couldn't use the full travel of their lift, they cut out the bottom chords of the joists to get more room.  
The roof was somewhat saggy.

RE: Structural Abuse

JKWO5

Thats a beauty, I'll remeber that one too !

RE: Structural Abuse

Consider the current thread in view of this one over in the Boiler and Pressure Vessel forum:
http://www.eng-tips.com/viewthread.cfm?qid=225000&page=1

Basically, the question is whether repads need to be provided under connection clips all the time.  The answer is no, but some just do it anyway.  But this kind of thinking gets applied to other things as well.  So we'll commonly see pipe supports specified at a maximum spacing of 5' or 8' or some other arbitrary number regardless of strength/design considerations.  So there is in fact a distinct possibility that in the original photo, the entire support may be superflous, and was furnished because someone just felt it ought to be there, and couldn't be persuaded otherwise, stress or no stress.

RE: Structural Abuse

Good engineering practice means designing some robustness into the structure. We know that over the 50 year life it is going to end up carrying more than the 2 - 3" compressed air lines it started with.
It's also likely to have minimum maintenance and an average of 2.4 hits from a 20 ton forklift.

RE: Structural Abuse

I was thinking about starting a new thread about something i thought it was stupid, but since i saw and read this thread i will place my question here.

I work on a construction company in Nicaragua, a client who is going to be in charge of building a road called us and said he needed a temporary storage/work shop facility, following their ideas we ended with this (pic 1). They think its too expensive for a temporary construction (its going to last until they finish the road, about 20Km). Now they want something like the sketch on pic 2. The two boxes you see are containers, they are thinking of using them as office's and as a warehouse, they want me to place the truss over the container, i'm not sure if this can be done (probably it has been done before, somewhere), my major concerns are overturning moments(the horizontal reaction of the truss is right around 6 tons and the vertical reaction is around 2 tons) and the anchorage on the containers steel sheet, i fear it might tear. I designed a structure (pic 3) to substitute the containers as structural elements, but they still want to use the containers as columns, they really don't want to spend enough money on this warehouse.

I need some help with this. Thanks.

RE: Structural Abuse

Further to Jed's saggy roof story.  Back at University our lecturer relayed a tale about an equally stupid person.

This chap lived in a run of the mill english detached house (brick walls, timber roof truss).  He was apparently an avid wood working fan and decided he wanted his own workshop, but lacked the space to put one in.  So, he decided he would use his attic.

He installed a pedestal drill, lathe and belt sander.  And to improve the working area he cut out the chords in truss.

This may be an urban legend, but snopes came up empty.

RE: Structural Abuse

(OP)
aapl2k7,

You need to start a new thread to ask this question as it is completely unrelated to the original topic.

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