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旧 2009-09-07, 11:25 PM   #1
huangyhg
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默认 cheating on retaining wall calcs

cheating on retaining wall calcs
i am planchecking some plans for various sized retaining walls. the engineer is using enercalc. the first thing i wondered is if the walls will need special inspection, so i looked down at the masonry data and saw that "no" has been handwritten. however, the engineer also included the wall diagram graphic, which says "spc insp" right on it. i noticed that this has happened on almost every wall. then i looked more closely, and on some of the taller walls the rebar sizes have also been handwritten, and this time the engineer corrected on the graphic too.
obviously this is unethical. is it something that i should report?

i am missing your point. can you be more specific? who is making the corrections? and where are the corrections are being made? are you a building official? if not, in what capacity are you checking the plans? are you doing a peer review? there ethical issues here on your end depending on your answer.
aci 530 mandates that all inspection be inspected. ubc, as i recall, left it up to the designer. i think not inspecting masonry is a mistake and it can yield some conservative designs that cost clients more.
please elaborate
i work for a private company that contracts with various jurisdictions to do plan checking on small to medium projects.
the designing engineer has provided a set of calculations with the drawings, and he is using enercalc for the retaining wall calculations. he has input his wall data and in most cases he has needed the increased stress values you get when you have the masonry specially inspected to make the walls work. enercalc then notes that he is using special inspection values, and he has whited out the word "yes" - meaning he needs special inspection - and handwritten "no".
these are not corrections - these are building department submitted plans and calculations.
i know that owners and builders are always pressuring engineers to avoid requiring special inspection, so i am can see why this guy altered the calculations - in fact, now that i've looked at the walls and run some numbers, it appears that he has also altered some (not all) of the reinforcing size and spacing such that the walls work without special inspection. why he didn't just rerun the walls and print out new calculations, i don't know. however, i also agree with you that not using inspection drastically increases the amount of reinforcing needed and often forces the use of 12" masonry where 8" would work with inspection.
i see your quandary. a few comments -
whatever you do, do it in writing. document what happens. produce those written documents with extreme care, potentially with advice from the city attorney.
generally, public entities have little choice in reporting unethical behavior, potentially dangerous designs or drawings that are so wrong that their production is a prima facie indication that the engineer who signed and sealed the drawing(s) is not competent. this would apply to your firm's assignment. however, ...
the issue of unethical behavior is tough to prove. if you can demonstrate that the design - as presented - requires special inspection in order to be accepted under the applicable building code(s), then you might have him on both the competency and/or ethics issues. but you will have to use the design method assumed by the applicable code as well as any other generally accepted design methods to demonstrate the error. most state boards won't do this - the complainant must provide it.
i think your first step is to contact the engineer and ask him to come by to discuss the matter. ask him to explain the changes, and to provide hand calculations to you to back them up. if he "arches his back", you have little choice but to file a complaint. if he can demonstrate the basis for his changes - and they are reasonable - you have avoided an unnecessary conflict.
the third scenario is thornier: what if he "confesses his sins" and asks to be permitted to withdraw the drawings from consideration? i don't think you can ethically permit that, but you need to check with the city attorney (also on contract?) and someone with your state board.
good luck, and let us know what happens -
burnaway - what is the city building code?
well, i read your elaboration and i read focht3 "s response. i really like his suggestion to invite the engineer and discuss with him the situation. i think he may have an answer that might satisfy your concern. if not, i would elevate the issue to the proper authorities.
we as engineers must place and make the public safety paramount in our practice. i can understand a minor mistake and oversight; but never a deliberate one!
good luck
generally in a submission the engineer should state why changes were made if documents allow the reviewer to be in doubt. i am sure that there is a reason for his/her modifications. as pointed out, there is a need to contact the engineer and give the opportunity to explain the situation. if there is need to correct then the opportunity should be provided as well. computer generated designs do not necessarily cover all situations. i am not sure of the program quoted but very often modifications are required to correlate with experience and reality.
you said you ran some numbers. was this done using the same program. is the program the acceptable standard within this practice. if so then there could be a different outlook. anyhow talk first.

i'm sorry - but i would be pleased if someone would define what is meant by special inspections! sometimes with computer programmes, they have a mind of their own in the notes - the author of the programme might want to limit his liability so he "special inspects" everything even should it not really be required. you need to get a handle on this too - i.e., the limitations of the programme. i applaud the point that it would be prudent to call the designer and ask him about the design - in general, not necessary to try to stick him on this point. properly handled, it will come out in your overall discussion anyway - and you should state your concern. without all the details and what a special inspection really means, perhaps the designer used the programme and decided that, in his considered opinion, the programme's requirement was not applicable in this case. perhaps. it is something to keep in mind.
oops - and by the way, "cheating on retaining wall calcs" might not have been a professional heading. you are calling the kettle black without even knowing if anything has ever been cooked in it.
"special inspection" was first called for in the ubc (i think) some 20 or 30 years ago; i've been aware of it for at least 15 or 16 years. cmu walls and drilled pier foundations are the most common elements that require special inspection (in my experience.) basically, the building code mandates inspection by a qualified independent third party, with reports provided to the building official as well as the owner and contractor. it beats the pants off the "let the owner/builder do what they want" system that i am currently dealing with -
while the heading isn't one i would have chosen, it certainly got my attention. perhaps the simple addition of punctuation - a "?" - at the end of the sentence would have avoided the potential for misunderstanding. and let's remember that burnawayfff"> is a relatively new, inexperienced
thanks focht3 - guess what the building code requires is what i consider normal inspection - having a qualified soils engineer inspect the soils (preferrably the geotech on record). as i deal/dealt with mainly heavy civil works (steel mills, refineries, etc.) it goes without saying that inspections that are considered "special" are actually expected .
i wasn't trying to be harsh on the title. it is attention grabbing, but . . . and, yeah, there really is a god (or diety whichever way you choose!!).
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