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RE: question my authority???!

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Yes, I have seen a contractor question the thickness of a wall that was to
thin.  He said it needed to be at least 18" thick not 12".  The engineer's
response was that "I analyzed it using the computer and the computer said it
was ok".  I got involved after the fact to re-analyze the wall because it
deflected and cracked.  It ended up in court.  The engineer calculated the
loads incorrectly and when checking the deflection used Igross and not
Icracked.  When using Icracked the deflections calculated were similar to
those measured in the field.

We have contractors (few) that will ask us to review a design because they
think it is not adequate.  When those contractors question my design, I
listen.

For what it is worth.  There are good contractors out there that know more
than I about getting things built right.

Gary W. Loomis, P.E., Senior Structural Engineering
Master Engineers and Designers, Inc.

-----Original Message-----
From: Gary L. Hodgson and Assoc. [mailto:ghodgson(--nospam--at)bellnet.ca] 
Sent: Monday, November 05, 2007 7:45 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: question my authority???!

This reminds of the time a customer came into my office yelling that I 
had cost him money as the footings were way over in size. I let him vent 
and then asked him how he knew the footings were over.  At first he 
wouldn't say but then he said the concrete ready-mix driver had told 
him.  Of course, everyone knows all these drivers have to have a degree 
in engineering.
Gary

Andrew Kester, PE wrote:
> Scott actually brings up a good topic, and all good jokes aside, I 
> think he needs to address this to the owner or client expeditiously 
> before the owner thinks he is an overdesigner. Many owners/developers 
> only care about the bottom line, and if they get a permit and C.O. 
> they assume all is well. Anything over that is just 
> overly-conservative engineering to them, and that can cost you 
> business. I am NOT always sure of the best way to handle these things, 
> but trying to speak directly with your architect or owner and explain 
> that you perform your analysis and calculations to the latest code 
> standards, and that you would gladly review an alternative design and 
> calculations by another engineer.
>  
> If this is during the design stage or prior to groundbreaking, you can 
> say "Well, let me review our numbers and drawings to make sure that 
> there was not a miscalculation or drafting error", and do just that. 
> We all make mistakes, sometimes it happens in the drafting stage, or 
> you fill out your footing schedule wrong or put the wrong footing mark 
> on the plans. Even if you are 100% sure and you simply look at your 
> drawings and say to yourself, "Man, I am so right" and call the 
> architect back and say you double checked but you believe your design 
> is to code, then you did your job and you will look better.
>  
> I would like to hear from our seasoned vets on this issue because as a 
> young small firm owner I need to have some options ready to save face 
> with owners and clients.
>  
> We have had this happen usually from a contractor who says one of the 
> following, or a combination of them, and many times not to us but to 
> the owner or architect:
> -We have never done it this way and I have been doing this for XXXX years
> -Engineer B down the street does it this way and he says it is fine
> -This is a complete waste and overdesign and is costing the owner lots 
> of money (which if I could save I would not return the money but 
> pocket it)
>  
> We had a single story retail building with a large covered canopy over 
> near the coast, and it was CMU with some CIP concrete arched beams. 
> Some contractor sub, probably slow from work due to the slow down in 
> residential/condo work, promised he could do the walls ALL in CIP 
> concrete rather than CMU cheaper than CMU (seems crazy to me, but 
> maybe he was really slow or had lots of forms and good subs). We get 
> an Ad Serv to redesign the walls, and the contractor flips out when he 
> gets our drawings as "we put way too much rebar in the walls and he 
> always does them with X amount and the engineer down the street does 
> it this way."
>  
> Now the walls were single story and the design was not governed by 
> strength but by ACI vertical and horizontal min reinforcement. We 
> copied that section of the ACI along with some simple hand calcs 
> showing why we could not space the bars and use the size he wanted to 
> use, and the owner saw this as well. After a pow-wow they dropped the 
> guy and went back to CMU. I am sure he made a promise he could not 
> deliver, and I do believe that another engineer does it that way 
> incorrectly (like 24" o.c. and #3 bars). Most of our plans reviewers 
> will pass anything with a PE seal on it....
>  
>  On a side note, in this instance, I have to think that the ACI max 
> spacing seems a bit too strict for a single story, lightly loaded 
> wall, when you can reinforce 8" CMU with #5 @ 48" o.c. , while I 
> believe off the top of my head we were limited to 18" o.c. for 
> concrete. I am sure it can be explained but it is odd that weaker CMU 
> requires much less reinforcement in the vertical direction....
>  
>  
>  
> Andrew Kester, PE
> Principal/Project Manager
> ADK Structural Engineering, PLLC
> 1510 E Colonial Ave., Suite 301
> Orlando, FL 32803
>

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