Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

My boss says look the other way? 17

Status
Not open for further replies.

transmissiontowers

Structural
Jul 7, 2005
560
I am a structural engineer and have been working for over 30 years analyzing transmission towers and poles that support wire. My boss is an Electrical Engineer with a PE. His boss is a business major. The Vice President is a Mechanical Engineer.

The problem is the analysis of towers with a skewed wind angle. Due to geometry, a wind at an angle will produce maximum loads and cause leg failure. If the wind is only considered normal to the wires, the legs are OK.

Back in the old days, we did not have the software tools to consider skewed wind. With better PC's and better software, we can now analyze hundreds of wind angles and determine which wind angle will control.

My EE boss says it is a management decision of risk vs reward and it costs too much to fix the towers when adding more equipment to the tower. As a PE, I feel it is my duty to inform him that it is my opinion that the tower will fail if the wind hits the maximum design wind speed and at the most critical direction.

The NESC code we work under has some generic guidance that the wind at an oblique angle may cause higher loads. Guying the tower inline will help brace it and reduce the leg loads to acceptable levels, but it costs more and the construction folks don't like to do it and are concerned with trucks running into the guy wires.

I have been told to ignore the oblique wind direction and allow the extra equipment to be installed on the towers. I have a few options:
1) State my concerns to the manager and let him decide
2) Run the oblique wind cases and note the failures, then run the normal wind case and note the loads and write a note in the file that the tower will fail in the right conditions.
3) Prepare a letter and have it signed by the EE and his boss that they are aware that the tower may fail.
4) Report my EE boss to the State Board of Registration for ethics violations.

Is it ethical for the EE to order me to look the other way?

_____________________________________
I have been called "A storehouse of worthless information" many times.
 
Replies continue below

Recommended for you

If the modern analysis methods you're using are generally recognized and accepted among peers in your dicipline then you're pretty much going to have to take it to the next level, particularly if you are a licensed PE.

In Texas and Colorado the fundamental basis for licensing is for the PROTECTING THE PUBLIC. You could be held liable if you don't. I'd pick through the respective engineering LAWS and quote chapter and verse but that would take too long. The wording is there though; think wistle blower protection laws.

You've probably already thought beyond the just a tower failure clear though to the guy on the operating table with his chest spread open when the lights go out (no UPS).

Check your engineering law; it should describe the necessary action you should take. Start documenting everything (gotta love email) but make sure your analysis is valide. How likely is the bad wind angle? Too bad the NESC code isn't less generic.

Go option 2 just to be sure then go back to your immediate supervisor and keep climbing until you have no recorse but to contact your state board.
 
Now that the geenie is out of the bottle i dont think you have any choise to to refuse to stamp the documents (or however this works in the US).

If it is a management decision then it shouldnt be your name on the documents - because im pretty sure that they wont remember the details if an accident should occur and your name is on the document.

Best regards

Morten
 
If your calculations indicate it will fail, then you have no choice but to document the findings and report it to management.

What is the wind and angle that will cause failure? What is the likelyhood of it occuring?

Greg Lamberson
Consultant - Upstream Energy
Website:
 
Good topic.

Risk vs. Reward: An analysis needs to be done to find out what the likelihood of that particular wind angle is. If the risk is within acceptable limits, then fine, but it is a management decision. You have done your due diligence and I agree with dtn, document EVERYTHING. Take copies of emails home, print them, put them in a safe, whatever you have to do to protect yourself.

I also agree with Morten, stamping drawings (i.e. taking responsibility) is a personal decision. Anyone can direct an engineer to stamp something, but the engineer has the right to refuse - without punishment. It has to be right.

In your case, if the management is satisfied with the risks, then that is their decision and someone else should stamp the drawings who is comfortable. It is tricky to balance financial obligations with safety. While I sympathize with your management, safety should always be a prime consideration.

I assume that they have listened to your concerns and reviewed the calculations. Hopefully it is not a case of them immediately dismissing it.

 
Citing Texas "Law" purely as an example:

137.55 ENGINEERS SHALL PROTECT THE PUBLIC
(c) Engineers shall first notify involved parties of ANY engineering decisions or practices that might endanger the health, safety, property or welfare of the public. When, in an engineer's judgement, any risk to the public remains unresolved, that engineer shall report any fraud, gross negligence, incompetence, midconduct, unethical or illegal conduct to the board or to proper civil or criminal authorities.
 
I think one of the issues here is the question of what are the governing codes?

Does the IBC incorporate by reference the TIA/EIA standards for example, or do any state or US regulations specify transmission tower design? If there are regulations in force and stamped calcs or drawings need to be submitted to a reviewing authority, then in my opinion the design needs to meet these design requirements. If there aren't specific legal codes but there are applicable industry standards then you and your company would have to defend, if there was a failure, why generally accepted engineering practice was not followed.

Regards,
-Mike
 
And that's the point I was making, I agree with sdl, if it is a 1,000 year occurrence that would cause a failure and you are looking at a 100 yr occurence (only an example) for the design, then it is a management decision.

Assuming it is a management decision, then a risk assessment should be undertaken. You mention the guys may cause a risk, all of that should be part of the equation.

Greg Lamberson
Consultant - Upstream Energy
Website:
 
I think Mike has identified the issue correctly. A risk vs. reward analysis is appropriate only if the there are no regulations, codes, or industry standards that apply. If there is a design standard, then the design should be evaluated on that basis, either yes it does meet the standard or no it doesn't.

If you sign and stamp an inadequate design as the engineer in charge, you will be held responsible and no memos or letters to management will absolve you.

If there is no required design criteria, then you should calculate the wind speeds and directions that the structure will support and include that information on the plans that you sign. Then management could dexide whether or not to go ahead with construction.
 
With 30 years in the business, let's assume transmissiontowers knows what he or she is doing. If he didn't, he wouldn't be a PE and still be in that field.

The question originally asked is a matter of ethics, not of his analysis method or approach. We've all offered our heads-up on being sure there's really a problem. Now, let's deal with the issue as presented, there's a problem.
 
Didn't want to give too much personal data but I am in Texas and a PE. I don't stamp drawings or calcs since the work is done for a large Electric Utility for internal use. We are adding PCS antennas to the top of our towers to generate revenue for the corporation and I have to analyze the tower for the extra loads. Lattice towers that are rectangular based have a problem with the narrow face not having sufficient leg spacing to resist a wind load on the wide face. There is a critical wind angle that produces maximum leg compression.

Back in the old days when it took days to calculate one load case and do an analysis by hand, we did not consider the wind at skewed angles because it was so calculation intensive. With modern software I can run 100 wind directions all around the tower in a few minutes.

We work under the NESC code book which has a few vague statements that an oblique wind may cause higher loads. With the ability to study the phenomenon in detail, I feel it is prudent to blow the wind all around and see which case is worst then strengthen the tower as required by replacing members or guying inline.

A few years ago, we had convinced the boss's boss that it was prudent to consider oblique wind but he transferred somewhere else and we now have a BA in charge and my EE boss wants to stop using oblique wind.

AFA risk, we design for a 50 year return period storm per NESC and just assume the wind direction can be anything possible.

I'm hoping that I can convince the managers that it is still prudent to blow the wind at oblique angles.

Thanks for the replies.

_____________________________________
I have been called "A storehouse of worthless information" many times.
 
If I were involved with this, I would inform the EE that with current improved methods of analyzing the system that it fails with the addition of new equipment and that a consequence of the new equipment that it requires modification. I would also ask him if the equipment be modified so that it works?

You should be confident of your analysis and suggest that you would be pleased if someone else review your findings. If you simply pass the problem on to others, you could still be unethical and also liable. If you refuse to seal or sign off on the design and someone else does, you can still be liable... If the design only marginally fails, then it is an engineering judgement if the possiblilty of failure is acceptable.

What is the EE's reason for suggesting that it is acceptable? Modification of something due to a change should be fairly common. Does it open another can of worms? I would approach the EE (It might be that he's EE and doesn't have an appreciation for the structural problem.) and let him know that the system is unsafe explaining to him why (if it is) and that for ethical and legal reasons, the problem must be addressed and that he should move the problem upward to the ME.
 
I preface this with I'm not a structurual engineer so I don't know the depth of the calculation issues and their relationship to "will if fall down", but I will comment on the chain of command and lack of action.

Engineers are employed to bring technical issues to the fore when the situation warrents it. This seems like the time! If your bosses don't want to get into this critical problem then you need to find someone who understand the scope of the problem. As you mount more of the PCS units the probability that one of the towers experience a problem will go up greatly.

I have been to Federal Court over a business matter, trust me it's not fun. Ask you bosses if you can check the findings with the company legal department and the general insurance provider for some feedback. If it is OK with them then you will let it go. Of course this will not occur with either of these groups. Also ask you bosses to sign off on you analysis and have them direct you to other "more important" work.

Maybe this will call them (your bosses) to act on what I feel is a very, very critical engineering discovery. This is not an easy spot for a moral person to be in. Good Luck.

jck26
 
"NOTE: Under the extreme wind conditions of Rule 250C, an oblique wind may require greater structural
strength than that computed by Rules 252B and 252C."

I suppose it might be possible to misconstrue the "may" above, but to me it is pretty clear they intend for you to build for the worst case. If you really see two interpretations, please contact IEEE for a formal interpretation.

Please note utility commissions try to make penalties high enough that compliance is cost effective. Are you really quibbling over the cost of guying? Guy markers will lessen the truck incidences. See 217C.
 
The EE boss is hanging his decision on the fact that we have analyzed and built these towers for 40 years and have not had widespread failures during hurricane wind events, but my point is we have not had a major storm hit with the PCS sites installed. Plus the fact that he will retire within a year or 2 and leave the mess behind for others to deal with.

The section 252D you cited above is the section that I interpret to mean I must consider wind at an angle. I am on ASCE committees with the people that write these sections of the NESC and the phrase you quoted has been in the code since 1977. The code is not a design standard but is a public safety code and has words that say in effect that I must design the structure to withstand all expected loadings.

I think I'll prepare a paper and note my assumptions and interpretations and present it to management. I am the highest ranking structural engineer at the company with bosses having EE's and BA's.



_____________________________________
I have been called "A storehouse of worthless information" many times.
 
star for transmissiontowers. your last post is taking your years of experience and using them to protect your company and the public. keep up the good work.

ZCP
 
transmissiontowers:

I am another that does not have an appreciation for the calculations and work involved (i.e. I am one of those idiots who hopes the bridge stays up when I drive on it). What I do have an appreciation for is our obligation: moral, legal AND ethical to do everything in our power to protect ourselves and others from harm.

Adding to the towers as "a revenue generator" is a change to the design and requires the due diligence you are talking about. It also sounds like it is not on every tower so I can't see the cost impact being that significant (compared to all towers).

Safety is being compromised for the sake of economics and should not be acceptable to anyone.

If it were me (thank you it is not), I would follow the suggestions of dik and approach him in a way that will help him understand. I come from an electrical and instrumentation background, so I cannot understand the technical issue without guidance. What are the costs? What are the schedule impacts? How much will the extra work increase the return on investment?

I will leave it with this comment:

BP at Texas City never had a serious problem before they killed 15 people. We simply cannot rely on past history as an indicator of our safety record. It deserves a pat on the back if it is good and lessons learned if it is less than desirable but that is all.
 
Years ago I was working on a safety issue for a piece of portable equipment that would fold up to be transported down the highway. As I was working on this the general manager walked in to see what I was doing. He became upset that I was adding cost to the equipment and said that I might as well just go out and tape dollar bills to machine. He mentioned that we had only one fatality with our equipment and that there are always risks. Out of disgust I found another job and left the company before the project was finished. I found out much later that the first machine built collapsed right where I thought it would when they pulled it out of the parking lot. Thankfully no one was injured. Of course the general manager blamed it on a poor design by engineering.

So transmissiontowers gets a star from me for his concern for public safety. Hopefully he can resolve this satisfactorily.

Regards,
-Mike
 
Since you have about 30 years experience, what method do you use for analyzing transmission towers? What frame progra? Is there a standard for loading/design? Is there an on line *.pdf file?

Dik
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor