Questionable Calculations 12

[Greatone76]

I have a situation where I’m monitoring a project as an owner’s rep. We have encountered a situation where the owner is requesting structural calculations to ensure an installation is acceptable. In doing this it has come to light in writing that the designers on this project took another project’s design documents and did not evaluate the original design. Along with that comment in writing when I reviewed the calculations produced I am seeing glaring errors in the calculations. I am asking about roof diaphragm blocking and the designer calculated the uplift forces on a truss and compared that reaction to the shear diaphragm capacity of plywood out of the code. They did not reduce the value from the table as required either. So I am seeing clear deficiencies in the small amount of calculations provided. I’m a licensed Structural Engineer in the state I’m working in. Knowing the Structural Engineering Statues in the state and knowing it is illegal to not evaluate a design you stamped for and seeing the glaring issues with fairly simple calculations…..

Do I have an obligation to report this to the state board as a complaint?

Can a complaint be made anonymously and are they reviewed in the same manor?

 

[manstrom]

You can probably file an anonymous compliant, but wouldn't you rather talk to the engineer and one engineer to another? Maybe they have done a thousand of these and don't need to check the roof diaphragm calcs.

There may be mitigating circumstances. Don't drag the guys name through the mud unless you've given them a chance to make things right themselves.

One thing I have learned is that if you are going to lay into someone, you better be damn sure that you are right.

When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.

-R. Buckminster Fuller

 

[WARose]

I agree with manstrom, especially if it hasn't been built yet: I'd try to resolve it with the EOR and fix it there rather than filing a complaint with the board. (You don't want to get a rep as someone who does that anyway when there are other avenues available.)

 

[graybeach]

I also agree with manstrom, and his advice is actually required in the ASCE code of ethics. That said, I work on the owner's side too and see egregious errors all the time. In 10 years of doing this, I haven't reported anyone to the board but probably should have in some cases.

 

[msquared48]

I agree too. Do not burn your bridges. Some day you may need the same consideration.

Mike McCann, PE, SE (WA)

 

[GeoPaveTraffic]

I agree with all of the above.

However, if the EOR doesn't provide an adequate response; then you have an obligation to file a report.

If we as engineers do not adequately police ourselves, then the politicians will.


Mike Lambert

 

[Greatone76]

The structure of the building is installed. These deficient calculations were the requested response from the EOR. They authorized changes that when I review make the building structural inadequate. That is why we requested calcs. In doing so we were essentially told they took a design and copied it without verifying the design. A structural engineer for the EOR company produced the calc comparing uplift against diaphragm capacity. Another engineer produced shear wall calcs that did not include the connection from the roof to the shear wall or the connection between the gable truss and the top of the stick built wall. A third engineer highered by the contractor produced connection Calcs between the roof and the shear wall and the gable truss and the stick built wall, but only produced Calcs for the out of plane loads. Meaning the direct wind pressure on the wall and ignored the in plane loads that are required to make these connections performs as the required shear wall. The shear loads are substantial and where I'm seeing no chance the installation is structurally adequate. The questionable and deficient Calcs are the response to the owners concerns. The typical project the cm does is heavy civil. The cm highers the designer. I'm assuming I have a situation where I have civil engineer versed in bridges and road loading stamping my project that happens to be standard wood buildings. In my opinion I feel I have the cardinal sin of professional engineering which is stamping something you are no qualified to design.

 

[woodman88]

Are you just looking at their calculations or have you calculated your own loads to check the connection? If you have done your own calculations do they meet the minimum requirements of the building code and current minimum engineering standards of the State?
What they have done may not be what you would have done. But you must look at what they could do before saying it does not work.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

 

[Greatone76]

They have single 16d toenailed nails at 24" o.c. Worth approx 92 pounds each meaning a shear capacity of 46 pounds per foot. The required shear load is at least 300 pounds per foot. We are talking connections that are no where close to being adequate for any reasonable required load between the roof and shear wall.

 

[WARose]

Even if it is built, I'd still give them an opportunity to fix it (it's up to the owner whether he will cover the costs or they will). And I wouldn't assume anything about the design engineer's background, it could be just a oversight on his part......just let him fix it first.

 

[msquared48]

Greatone76:

If this the nailing of the wall plate to the floor diaphragm, did the shear wall sheathing continue to the top of either the sill plate or wall double top plate below? If this is the case, then the 16d would have only to transfer the story shear, not the total shear.

Just a thought.

Mike McCann, PE, SE (WA)

 

[Greatone76]

The change that was approved was from a direct connection from the roof sheathing to the double top plate of a shear wall that continued up to the roof level. This is a one story building. Instead of this the truss manufacturer submitted a gable truss that came out presheathed. They also had the roof overhang cantilever sit on top of the gable truss. The cantilever pieces sitting on top of the gable truss are attached to the roof sheathing and then only attached to the gable truss with single nails in each member giving me the single toenails at 24 in o.c. Also because the gable truss came out with sheathing the sheathing is broken between the gable truss and the top of the stick built wall, so the connection between the gable truss and the top of the stick built wall now becomes critical because the sheathing does not connect between the 2. They used more nails in this connection but I'm still seeing values that do not match the required loads there either.

 

[woodman88]

Could you give us a sketch of the detail?

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

 

[Triangled]

We of course do not have calcs in front of us, and, feeling sentiment expressed unanimously here and wondering why you don't talk to them?

Regarding your...".. capacity of 46 pounds per foot. The required shear load is at least 300 pounds per foot..."
What did they say?
a) "Yea, so what, we don't care."
b) "We disagree and here is why."
c) "omg, Thanks for catching that! We will rectify immediately!"
d) you haven't talked to them.

Regarding your... " Knowing the Structural Engineering Statues in the state and knowing it is illegal to .... " then you also where to find the answers to your a) "Do I have an obligation to report this to the state board as a complaint?" and b) "Can a complaint be made anonymously and are they reviewed in the same manor?"

Just curious as to what lies behind your wish for Anonymity, GreatOne ?

 

[Greatone76]

Attached is a quick sketch of the detail.

 

[Greatone76]

The CM is part of a large organization and the owner is part of a larger organization. I'm a contractor to the owner. I have no avenue to make the connection to the EOR. I've done my job in alerting to the owner to the problem. I've gone above and beyond using my structural knowledge to educate them on the severity of the situation. I'm a peon on this project that shouldn't have the education, background or professional liscene I have.

I don't want to report anyone anytime. But my concern is that I'm aware of a situation that appears to be a problem. I'm looking for some advice on how to proceed. I don't have a clear way to simply communicate with the engineer. I understand that would be the best and I believe the owner has asked the question and it is going back to the engineer. If and when it gets ignored I'm trying to figure out what I'm obligated to do and what I can do and what others would do.

 

[msquared48]

No vertical blocking at over framing?

No kickers at wall double top plate to roof?

Mike McCann, PE, SE (WA)

 

[Greatone76]

No blocking at the over framing. There is a single kicker at the middle of the wall.

 

[SLTA]

Is there a name on the stamp on the drawings? Get their contact info through the licensing board (readily available through my board, at least) and call the engineer directly. The owner may not realize that this actually matters, or care. Hopefully the engineer will.

If the engineer doesn't, then your status on the project doesn't matter at all; file a complaint with the board. Document all your attempts to get this issue fixed, and do the right thing.

Please remember: we're not all guys!

 

[dcarr82775]

For the love of God, call the darn engineer directly! Your avenue is called a telephone. I have done it a few times when I have no direct contractual relationship with the engineer.

Your concern appears warranted. By your sketch your primary concern is also easily fixed in 1 hour by a guy with a nail gun.