Welding steel cable? 1

[SteelPE]

I have to go look at a job tomorrow where a client just had a horizontal cable rail installed on his deck. He stepped on one of the cables (I have no idea why) and it broke. He doesn't have confidence in the system anymore and he us bringing me in to look at it. He is saying that the ends of the cable are welded to a nut at each end and I'm wondering if welding steel cable like this is even possible w/o causing a problem? I know they make special adjustable ends for these systems, why one was not used i do not know.

FYI, I did not design the original system and I am being brought in after the face.

 

[racookpe1978]

I suspect also that the "protesting" engineer (not a "testing engineer") stepped on the lower cable and bounced a few times.

Also, it is possible (probable) that the cable was over-tightened to appear straight, rather than only tightened enough. At low angles of deflection, you need a lot of pre-tension to be straight under load. But above comments are correct, you really do need to start with a reputable "cable-handrail" supplier first.

 

[zcp]

Suggest you follow up and make sure it is removed and the contractor does not just provide a 'deduct' for it. Due diligence / safety of the public. Just email them until you get confirmation it has been changed.

ZCP

http://www.phoenix-engineer.com

 

[SteelPE]

The items are in the process of being removed and the client would like me to make another visit to the site once everything is complete but..... How can I be held responsible if I was only asked to give my opinion on the existing cables? I provided my report saying that the cables did not meet code and they needed to make accommodations to correct the issues. I was not asked to come up with a repair. I gave my report to the owner, if the owner decided to do nothing I would think he would be held responsible as he did not follow the direction of the engineered he hired to review the item.

As a side note, I spoke to the owners rep the other day and they were granted occupancy by the city (a very large city) with the cables in their existing condition. Don't know why the city inspector didn't say anything.

 

[zcp]

You turn it into the next phase of work with a scope/schedule/cost to handle new design and coming out to see if it was installed per the design!

ZCP

http://www.phoenix-engineer.com

 

[dhengr]

SteelPE:
I don’t usually carry the water for the local building officials or code officials, but if it doesn’t look like an absolute piece of junk, they might overlook it, if they don’t have the negative inclinations about these systems that I mentioned in my earlier post. It looked about like the typical installation of this type of product, and that’s as far as they took it. They probably don’t test every connection to just short of failure; they probably don’t check the dia. of all the nails in the building, or the thickness of all the plumbing fittings etc., either. I’m more upset with them, that they think they should have my every calculation, design sketch and project note for their files. Two thirds of those people can’t interpret or understand them anyway, and I’m not in the business of giving plan checkers a short course in Structural Engineering and then answering their questions on minutia; but now they are their in the public domain for some hungry attorney to check and see if I dotted my I’s and crossed my tees, never mind the general correctness and completeness of my design. They don’t have a right to my inter-office memos, e-mails and love letters during the duration of that project either. Most of the time (many times) the project problem is the fault of someone other than the EOR, and it shouldn’t be so easy to fault the engineers because he left a calc. step out during his design, despite the fact that the calc. is basically correct. They are damn sure to keep us (P.E.s) responsible, we are the easiest target, they know they can get something out of our insurance. Other designers get off with a ‘please quit doing that kind of work and getting caught doing it.’ This poor product, intentional deception, should fall right back on the builder and the railing installer. If they provide a cheap product or system which doesn’t work, it is their fault, not mine, not your’s, because I happened to walk by the site one day, and I’m a P.E.