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Failures due to Inadequate/Improper Inspections
- Thread starter Ripz
- Start date
JedClampett
Structural
Since every failure has a set of root causes, you probably could justify listing any major failure (Hyatt Regency, American Flight 191, etc.) that were not strictly due to bad design as having an inspection component. (Although probably less at the Hyatt, as they did install to approved shop drawings)
But it's very seldom as simple as just blaming poor inspection, either. How about the installer who got it wrong? You can't necessarily always inspect away bad work.
But it's very seldom as simple as just blaming poor inspection, either. How about the installer who got it wrong? You can't necessarily always inspect away bad work.
As with many other types of production/fabrication, waiting for a final test (inspection) is often too late and too little. Certainly, in the electronics world, at final test, much of the system is no longer observable or testable. Likewise, in buildings, unless you perform some sort of destructive testing or inspection, much of the building is not inspectable.
The more spectacular a failure, the more likely it is that a chain of mistakes was involved. NASA's infamous Mars orbiter with the units mismatch error was later determined to have thrown clues that something was wrong from the very first course correction on the way to Mars. Every course correction executed was not as predicted by the flight models, yet, no one bothered to investigate. There should have been catch points in the interface control document (ICD) that were missed. No one tested, or checked test results, during ground testing.
TTFN
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Need help writing a question or understanding a reply? forum1529
The more spectacular a failure, the more likely it is that a chain of mistakes was involved. NASA's infamous Mars orbiter with the units mismatch error was later determined to have thrown clues that something was wrong from the very first course correction on the way to Mars. Every course correction executed was not as predicted by the flight models, yet, no one bothered to investigate. There should have been catch points in the interface control document (ICD) that were missed. No one tested, or checked test results, during ground testing.
TTFN
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Need help writing a question or understanding a reply? forum1529
msquared48
Structural
I can think of several in countries outside of the US where payoffs and bribes are commonly used to grease the wheels. Not that that doesn't occur here...
Mike McCann
MMC Engineering
Mike McCann
MMC Engineering
- Thread starter
- #5
Ripz,
I am probably nitpicking here, but...
"Inadequate/improper inspection/integrity practices" ought to not the primary cause of any failure. The failures are caused by sloppy work, bad materials, and unforseen conditions. Inspection would have caught a lot of this stuff. Insisting on minimal qualifications for the people doing the work would have prevented some of it, with or without inspection.
--
JHG
I am probably nitpicking here, but...
"Inadequate/improper inspection/integrity practices" ought to not the primary cause of any failure. The failures are caused by sloppy work, bad materials, and unforseen conditions. Inspection would have caught a lot of this stuff. Insisting on minimal qualifications for the people doing the work would have prevented some of it, with or without inspection.
--
JHG
I seem to recall hearing about the big hotel/casino in Las Vegas that was finally demolished (I think)- and one of the major issues was incorrect placement of rebar, which was not caught by the inspectors. Don't recall the name of the place.
There was a 15-story or so condo down in Corpus Christi or maybe Padre Island that was demolished in a similar fiasco, but I'm think that was soil movement problems there.
In both cases, nobody was hurt, so it was a business disaster but not front page news other than locally.
There was a 15-story or so condo down in Corpus Christi or maybe Padre Island that was demolished in a similar fiasco, but I'm think that was soil movement problems there.
In both cases, nobody was hurt, so it was a business disaster but not front page news other than locally.
JedClampett
Structural
JStephen, you're correct that inspections were a factor. But so was expedited design, rushed construction and a drastic change in the economics of the project. One issue that's come up recently is that the stirrups were too long to fit in the slab, the contractor cut them off to fit, and the hooks that the development depended were removed.
See thread507-305791 for some links and discussion.
See thread507-305791 for some links and discussion.
The Harmon Tower is still standing at the moment. Looks like now they will demolish it piece by piece, rather than imploding it.
The major issue was the core coupling beams.
The major issue was the core coupling beams.
- Moderator
- #10
How about shoddy inspections of existing structures that fail to assess the effects of aging, or premature corrosion?
Two people died and 20 others were hurt when part of the roof of the Algo Center Mall in Elliot Lake caved in on June 23rd of last year. But while the country was consumed by the story of the rescue and recovery effort, problems with how the mall was built remained untold, until now.
20+ Year old mall.
Maclean‘s Senior Writer Michael Friscolanti says the original architect of the mall tried to convince the developer not to put rooftop parking over the stores but his concerns were ignored.
“He told the developers numerous times, ‘I don’t think this is a good idea, I think we need to perhaps come up with a solution, perhaps underground parking, perhaps a parking garage on the side the building,’” Friscolanti explains.
.............................
Friscolanti also found the engineer who oversaw the mall’s structural design didn’t exactly have a sterling reputation.
“After this mall was built in the ’90s, he was pulled in front of the regulating body for engineers in Ontario and had his license revoked for two jobs that he did. ................."
The engineering firm that inspected the Algo Centre mall just 10 weeks before the roof caved in declaring it “structurally sound” was also disciplined by regulators and was preparing to close down.
Cass posted in The Pub a while back an issue with an inspection which did damage to a roof membrane leading to subsequent water damage.
There have been numerous bridge collapses when in routine inspections were either omitted, failed to identify issues or issues found in inspections were not addressed.
Not quite the same as construction inspection shortcomings, but inspection issues nonetheless.
Bill
--------------------
"Why not the best?"
Jimmy Carter
Two people died and 20 others were hurt when part of the roof of the Algo Center Mall in Elliot Lake caved in on June 23rd of last year. But while the country was consumed by the story of the rescue and recovery effort, problems with how the mall was built remained untold, until now.
20+ Year old mall.
Maclean‘s Senior Writer Michael Friscolanti says the original architect of the mall tried to convince the developer not to put rooftop parking over the stores but his concerns were ignored.
“He told the developers numerous times, ‘I don’t think this is a good idea, I think we need to perhaps come up with a solution, perhaps underground parking, perhaps a parking garage on the side the building,’” Friscolanti explains.
.............................
Friscolanti also found the engineer who oversaw the mall’s structural design didn’t exactly have a sterling reputation.
“After this mall was built in the ’90s, he was pulled in front of the regulating body for engineers in Ontario and had his license revoked for two jobs that he did. ................."
The engineering firm that inspected the Algo Centre mall just 10 weeks before the roof caved in declaring it “structurally sound” was also disciplined by regulators and was preparing to close down.
Cass posted in The Pub a while back an issue with an inspection which did damage to a roof membrane leading to subsequent water damage.
There have been numerous bridge collapses when in routine inspections were either omitted, failed to identify issues or issues found in inspections were not addressed.
Not quite the same as construction inspection shortcomings, but inspection issues nonetheless.
Bill
--------------------
"Why not the best?"
Jimmy Carter
"There have been numerous bridge collapses when in routine inspections were either omitted, failed to identify issues or issues found in inspections were not addressed."
The 'gusset' panel failure on the Minneapolis Interstate bridge. Decades of data showing a steady corrosion rate [due to pidgeon poop?] and areas where the thickness was HALF GONE. Started out at 3/4", last measurement [that MN DOT admits to] had areas at 3/8". Further, the original design of this box-girder truss bridge was done 'by hand' just prior to computers for engineers and scientific calculaters. The Minnesota DOT couldn't be bothered to recheck this fracture critical area of their bridge when truss software became widely available. I believe the computer calc's came out to 1-1/8" required thickness, vs. the hand-calc'd 3/4". But 3/4" would have held the load, with a reduced safety factor.
[RANT]
Steel bridges in general are a MAJOR sore spot for me. The morons at DOT's all want to make everything a major project, including chipping off peeling paint and doing spot-touchups of those chipped places. When you force a simple 3-man job - chipper/painter in bosun's chair, helper, boss - to become a $200K contract, nobody can figure how to fix the rusty spots. The navy's of the world have proven that with regular chipping & painting, steel structures last 'forever' in corrosive environments. And some navys have also proven that 'benign neglect' of paint will cause major, relentless, and rapid failures of those steel structures. Concrete is a lousy bridge material, but if you're too stupid/lazy/'politically adept' to fix the paint, concrete beats steel.
[/RANT]
The 'gusset' panel failure on the Minneapolis Interstate bridge. Decades of data showing a steady corrosion rate [due to pidgeon poop?] and areas where the thickness was HALF GONE. Started out at 3/4", last measurement [that MN DOT admits to] had areas at 3/8". Further, the original design of this box-girder truss bridge was done 'by hand' just prior to computers for engineers and scientific calculaters. The Minnesota DOT couldn't be bothered to recheck this fracture critical area of their bridge when truss software became widely available. I believe the computer calc's came out to 1-1/8" required thickness, vs. the hand-calc'd 3/4". But 3/4" would have held the load, with a reduced safety factor.
[RANT]
Steel bridges in general are a MAJOR sore spot for me. The morons at DOT's all want to make everything a major project, including chipping off peeling paint and doing spot-touchups of those chipped places. When you force a simple 3-man job - chipper/painter in bosun's chair, helper, boss - to become a $200K contract, nobody can figure how to fix the rusty spots. The navy's of the world have proven that with regular chipping & painting, steel structures last 'forever' in corrosive environments. And some navys have also proven that 'benign neglect' of paint will cause major, relentless, and rapid failures of those steel structures. Concrete is a lousy bridge material, but if you're too stupid/lazy/'politically adept' to fix the paint, concrete beats steel.
[/RANT]
TXStructural
Structural
Duwe, the MN bridge was originally built with the wrong thickness gusset plates on one end because of what amounts to a scrivener's error in the original CDs. The smaller plate proved adequate until it did not (unbalanced construction loads, age, fatigue, wear, corrosion...)
And as a forensic engineer I know is fond of saying, "gravity is the cause of most failures". Drawoh has it right, it is not a lack of inspection that causes failures, just like a headache is not caused by a lack of aspirin.
We should be cautious about how we phrase our public comments, and fixing how we think about these things is a good start. Inspections and other construction quality control measures are important in avoiding construction defects, but the principle responsibility rests with the construction company and those individuals doing the work. Shoddy workmanship cannot be tolerated at any level.
Also, designs which are unnecessarily complicated and do not consider constructability are just as responsible for these problems as the construction itself.
And as a forensic engineer I know is fond of saying, "gravity is the cause of most failures". Drawoh has it right, it is not a lack of inspection that causes failures, just like a headache is not caused by a lack of aspirin.
We should be cautious about how we phrase our public comments, and fixing how we think about these things is a good start. Inspections and other construction quality control measures are important in avoiding construction defects, but the principle responsibility rests with the construction company and those individuals doing the work. Shoddy workmanship cannot be tolerated at any level.
Also, designs which are unnecessarily complicated and do not consider constructability are just as responsible for these problems as the construction itself.
"The morons at DOT's all want to make everything a major project, including chipping off peeling paint and doing spot-touchups of those chipped places. When you force a simple 3-man job - chipper/painter in bosun's chair, helper, boss - to become a $200K contract, nobody can figure how to fix the rusty spots. "
DOTs don't make the laws and policies for procurement; it's a political tool, so every $200K contract is because there is/was political capital to be spent.
Of course, the "hand calcs" were probably done by the nephew of the cousin of the ..., which was so much better than it is now.
TTFN
faq731-376
Need help writing a question or understanding a reply? forum1529
DOTs don't make the laws and policies for procurement; it's a political tool, so every $200K contract is because there is/was political capital to be spent.
Of course, the "hand calcs" were probably done by the nephew of the cousin of the ..., which was so much better than it is now.
TTFN
faq731-376
Need help writing a question or understanding a reply? forum1529
- Thread starter
- #14
There will always be cost considerations and compromises made of this.
Simple example. We can use Carbon Steel to transport Fuel, because it's corrosion rate is low. But everything corrodes, so we get around this by having Inspections done routinely to determine the rate of corrosion and the likely remaining life to plan for intervention.
Sure, you can replace with Stainless Steel and not have to worry about this, but the fact is, cost plays a considerable factor in most decisions, and using Carbon Steel for fuel is not a poor practice, but the inspections are necessary.
Should inspections fail to detect corrosion that led to a hole that led to a fire; we can't now say that the designers were at fault for using Carbon Steel when Stainless Steel would have been better?
Simple example. We can use Carbon Steel to transport Fuel, because it's corrosion rate is low. But everything corrodes, so we get around this by having Inspections done routinely to determine the rate of corrosion and the likely remaining life to plan for intervention.
Sure, you can replace with Stainless Steel and not have to worry about this, but the fact is, cost plays a considerable factor in most decisions, and using Carbon Steel for fuel is not a poor practice, but the inspections are necessary.
Should inspections fail to detect corrosion that led to a hole that led to a fire; we can't now say that the designers were at fault for using Carbon Steel when Stainless Steel would have been better?
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