I could not agree more. I used to build what I now design and have found both engineers and mechanics who are incapable of performing their assigned jobs if there is not someone there to hold their hands. The bigger the project or organization, the more likely these guys are to slip through the system and ride their way to retirement on other people's coat tails.
There were two additonal factors not noted above: 1) In the construction, the two rods were offset in a common block instead of inline. Then the load was side thrust as well as tension pull. 2) The people on the catwalks were dancing. Therefore when keeping time with the music all dancers feet were impacting at one time which greatly increased the dynamic load. Anyone who has ever marched across a suspended bridge understands the meaning of this and knows why the Rout Step command was issued, Once the bridge was crossed evryone was again put in cadence.
I have worked on both sides of this problem, as both a field technician and as a registered professional engineer.
This problem cuts both ways. Experienced field installers know that there are some engineers who rarely get away from their cubicles. These installers don't have time to get in to a war of words with someone who doesn't know the situation on the ground; so they deviate from the design.
This is why we have "As-Built" Drawings.
Sometimes, however, the installer did not understand what the Engineer was asking for. It used to be that a phone call from the job site was expensive. Well, that's no longer true. I always recommend communications. If the installer didn't plan a few phone calls in the schedule for the work they bid, that's their own fault.
RPCY, the original design wasn't even marginal; it was able to hold only 60% of the minimim load required by the city building code. The bad choice for redesign meant the 4th floor structure would hold only 30% of the load required by the city building code.
The original design wasn't strong enough, required rediculous threaded lengths, and was poorly considered because the rods passed through the welded joint of two C-channels (making a rectangular tube).
The deformations of the 4th floor beams is just plain scary.
My experiences with assorted contract installers have mostly been negative. Some of them got all of the connections correct but wasted huge amounts of wire, others have made errors in labeling wires, so that each end had a different number, one time a panelman skipped one terminal, and so half the wires were one terminal over from where they should have been.
I have been fortunate that when it came to working on live systems I was able to do that myself, since I could move a bit slower and be more careful than the people eager to finish and leave for the next job.
Fire panels are unique in that they are indeed supervised, and that does add a requirement to accomodate the supervisory function. Mostly that calls for careful attention to polarities and diode directions, so it is not hard, but tedious.
Interesting comment about Ft. Hood. The last company I worked for got the contract for some expensive custom products (to protect the guilty, I won't say what) that were going onto some buildings that were being decomissioned. I got the job to do the design work and enjoyed it. But I had to demonstrate that it would work before the Army Corps of Engineers would allow us to install. While they were in our prototype lab, I asked what I thought was an innocent question, "Why were they installing this very expensive equipment on buildings that wouldn't be used." They glared at me and said they had budget money to use up.
As an aside about the Army Corps of Engineers, I had found a substantial technical flaw in their standard bid document for our type of products. I wrote a letter to Huntsville, AL (pre-email days) detailing the problem. About a month later, I received a letter back stating that I was correct and they would update their documentation. Eight years later, when I left the company, we were still getting the erroneous bid requests.
THE FIRST THING I SUGGEST IS THAT YOU FIND OUT IF THE CONTRACTOR IA LICENSED AND CERTIFIED TO WORK ON FIRE ALARM/RELEASING PANELS. REQUIRED IN MOST STATES. A RANK BEGINNER SHOULD KNOW THAT ANY INPUT "ABORT" IS LOOKING FOR A CONTACT CLOSURE AND OPERATES IN THE MICRO OR MILIAMP REMGE. BY TIEING IT TO THE NOTIFICATION CIRCUIT YOU ARE DUMPING 1 AMP IN TO THE CIRCUIT. SO FAR AS INDICATED YOU HAVE BEEN LUCKY THAT THE ELECTRONICS HAVE NOT BEEN FRIED. FOR THE SAKE OF YOUR LIABILITY ON THIS PROJECT YOU SHOULD COMPLETELY TEST PANEL WHEN THE PROJECT IS DONE.
You're thinking of the Hyatt Regency walkway collapse in Kansas City MO, 1981. The original engineer's design was workable but marginal, calling for two suspended catwalks to be suspended from the same 40-ft threaded rods. When the builder got to that part of the construction, he balked at threading nuts and washers 20 feet onto each rod, so he made what he thought was a reasonable compromise: he'd use two 20 foot rods instead of one 40 foot rod. The top catwalk would hang from the ceiling, and the bottom catwalk would hang from the top catwalk. He ran this proposed change past the inspectors, the chief project engineer, and a few others, and they all approved the change. I use this example sometimes when talking to validation crews, because you don't have to know anything about civil engineering to realize that if the joints where the top catwalk transfers its load to the rod was workable in the original design, you now have two catwalks hanging from that stress point. Nobody seemed to realize this. And even at twice the weight, the joint held when first constructed. It was only when the catwalk was filled with holiday revelers that the joint finally failed, crashing the lower catwalk to the ground, and the upper one pancaking onto it. The contractor's original bonehead error managed to sneak by several other engineers and get approved. It is not clear that the original architect/engineer was ever consulted on this change -- you'd think that if anyone would have picked up on this gaffe, it would have been him/her.
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