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旧 2009-09-15, 05:51 PM   #1
huangyhg
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默认 relevancy of code date-opinions sough

relevancy of code date-opinions sought
background:
united states project, texas, along the gulf coast. a public works project for the local municipality was started in 1999 and then "put on the shelf" by the municipality (for various reasons unrelated to engineering that i will not get into) while the project was at a 70-80 % level of completion. it was restarted in late 2000 with the municipality demanding 100% (not final) submittal within a couple of months (very very little money for restart-up). at the end of 2 months drawings were stamped 100% whether they were or not and submitted to municipality for final review and comment. the project was once again shelved after submittal. now in 3rd quarter of 2004 the project is once again re-starting, probably actually start in november (+/-). we are to submit a proposal for re-starting and completing the project. this would be fees associated with restarting a shelved project and does not include any original design fees (not that there is any money left.) initial phase of project is approx. 3 million dollars. i'm purposely not giving out specific details, sorry.
my question:
as the structural eor i designed for the latest codes at the commencement of the project in 1999. codes used: local building code sbcci 1997 (it just ref. the other codes), asce 7-95 (didn't have 1999), aci 318-99 & 530-99, aisc-lrfd 2nd. ed. (1995), and aisi-cold formed steel design, 1996. would you estimate hours based on redesigning/checking original design for the latest design codes? or, would you assume the codes used at the time are relevant and no need to check for code difference? i think all of the current codes are 2002 except the local code now ibc 2003. ibc ref. the other aformentioned codes but no dates.
if the project was completed in 1999 and the local municipality waited to start construction, i see no reason why they would come back to the engineer to verify design was still applicable. i don't believe they are under any obligation to check with the engineers and i know of no requirement from the state board requiring that the latest codes be used in all designs. but, to me it would be good engineering practice to verify code changes wouldn't affect the design, on the other hand would 5 years really make a difference? you see where i'm going with this...baffling.
thanks for your time.
vq

you have to design the project for the code that is current at the time of submission for building permit. the governing agency (city or county) reviews submissions relative to the currently active code, not some code applicable in the past.
so your fee should be based on a re-design / re-check of all relevent code provisions in the new code.
ibc 2003 does reference dates on the associated reference documents - see chapter 35 in the ibc for the relevent editions of aci 318, asce 7, etc.
you have an professional obligation to check and re-design by the latest code. if the latest code requires larger member sizes, then you are obliged to indicate that on the construction documents. if the latest code requires smaller
jike,
since i have a "professional obligation" to design by the latest code, do i go back to all my previous designs in my life and tell the owners that i have to check that previous designs meet the latest codes? and if the latest codes mean larger beams is my design inadequate? who says i have an obligation to use the latest codes? i guess the building codes as jae pointed out but, i could see the municipality saying no to current codes to save money.
i have an obligation to provide my client a safe economical design that also protects me from the unknowns in construction and from the unknowns of this litigious society.
i know it sounds like i'm arguing jike but it's more a rationalization. does 5 years really change a design? i look at 50 year old structures that have survived several hurricanes which makes me stop and think about codes and there 3 year cycles that they all seem to be going to. it feels more like a fleecing by codes writers than a necessity.
jae,
thanks for pointing out ch. 35, i missed the obvious.
vq
there is a decided difference between a building that exists versus one that is still being designed.
otherwise, you would logically be able to argue that you should be allowed to design to a code that existed 100 years ago, because you can find a building from that time that still stands. that argument is completely fallacious.
the fact that the customer will incur additional cost because they were inept in managing the project is not your problem. had they completed the project on schedule, the structure would be grandfathered into the existing code.
and yes, 5 years can make a difference. just consider what was required prior to any number of building disasters and that required immediately afterwards.
ttfn
your obligation is only to the project that is still in the design phase, not to older projects that have been designed and built under previous "governing" codes. your obligation is to design your current project by the current "governing" code, which may or may not be the "latest" code.
as jae said, the governing building code usually references the particular addition that you need to use for aci, asce, etc.
i certainly think that the changes to the various codes over the years have affected the designs. a few of the ones that come to mind are asce 7 wind, asce snow drifting, the 1/3 increase, the new load combinations, the masonry rebar laps per ibc, etc.
compare the damage to structures designed and built in florida before hurricane andrew and those after. how about northridge? i am sure there are many other examples also.
thanks for all you comments and taking the time to respond. i'm sure everyone is busy and i appreciate the time you took.
the 50 year old building...bad bad example. i'd never design to an old code. sorry for that one. in a seismic area i see 5 years making a difference. in wind design the big change is using the use of 3 second gust which has been around for several code versions. the calculation of pressures is primarily the same but the wind speed maps have changed.
but, i don't consider 1 or 2 code revisions to be old and as you pointed out jike there are many municipal communities (building divisions) not using the latest codes. if the latest version of a code was a must would not aci, aisc, sate agencies, etc. require/insist engineers use the latest.
the question in my mind is, will a slightly older code version make a difference and cause failure and i can't see that it will.
i ask myself;
1)will the building fail by using slightly older code? no
2)will it save the client money by staying with the older code and assuming the client says in writing to use the older codes? yes, in engineering fees
my goal is always to provide the client with a good safe economical design that will withstand the loads imposed and provide a good service life. ultimately i see no reason to ask the client to spend additional money because of a change in code in this area at this particular time and i haven't seen a valid reason to lead my to any other conclusion.
yes there are advances in codes, yes there are disasters, and yes we try to meet those disasters with changes in codes but from a wind standpoint, i think the changes in design as a result of a hurricane like andrew (aug. 1992) in florida are primarily design/construction detail changes following load paths and adequate connection/restraint design/check.
am i a bad engineer for asking this question or having this opinion? i hope not.
thanks guys for your time.
vq
in this situation i agree with vq, perhaps if you also place the applicable codes in the general notes, it would help with future modifications to the structure and thus no confusion, while also allowing permit people (albeit at a late stage) to check if it is acceptable, thus if it comes back to the owner, then there is a legitimate reason for redesign and checks.
regards
vod
when you submit your proposal you could state that your fee is based on the original design and codes and that review to the current codes would either need to be negotiated or you could give a fee as a supplement should your client elect to go with the review of the newer code versus the as-designed code. judging by your comments it sounds as if you are not sure what the relevant changes to the codes are and how (much) their changes affect your design? your client probably does not know either but they are looking to the professionals to tell them.
ultimately you and we are in business to make money while at the same time ensuring the life and safety of the general public that utilize our products/structures. you need to do some research to determine what impact the new code has on your design: either buy the new code(s) and review by chapter, and/or talk to your associates in other firms that have become familiar with the newer code. if i was your client i would look more favorably on your services if you told me straight up that it would cost $x to review for the newer code and that you did anticipate what the impact the newer code requirements will have on the design; both from an engineer's fee and potentially construction costs.
code compliant design is "point in time" specific. it is not retro-active unless more than a certain percentage of the project is to be revised, reconstructed or added. that percentage is usually 25% but can vary by jurisdiction. that only applies to projects that are being constructed or are already built.
as jae said, you must design for current code and therefore must review old design and upgrade as necessary. also, don't be shy about asking for compensation for this. you've been made to jump through hoops for this project and now it's time to stop giving away your services and ask for appropriate compensation. if a lawyer were providing his services on a project that had this happen, you can bet he'd charge for all review, checking current statutes for applicability and any other legal stuff he could throw in. and he'd get it!......i assume that since 1999 your rates have increased as well. make sure that gets covered!
some clarification. it's a municipal client and they or an entity within governs the local codes. if the client agrees to not update design to current local requirements they would likely have to do it in agreement with building code division.
once again, why not maintain the original design codes? because the codes changed doesn't seem to be a valid reason to spend the money. to design per the current governing codes is a nice linear and simple answer but i question my motives for picking the easy answer. there is engineering judgment involved and i want to make a good valid and justified decision. is my design invalidated by the latest code just because it hasn't been built yet? my answer to that is no. so then how do i justify asking the client to pay me more money to update the design if i can't justify it with sound reasons.
ron, i don't see a structural reason why i "must design for current code" as you stated. if i started a design right now, i would use the current codes. i have used valid codes and design procedures and as i stated above i can't see the design invalidated by an update in code. you could throw liability into the mix but with no national code body requiring/demanding that i always use the latest code and knowing that in this application the design is structurally sound as is, i don't see the "must" justified.
i'll likely present 2 options to the client at current dollars. any design package would state design codes and dates on general notes sheets. i have no doubt that my company does expect full compensation for having to pick-up this project years later, now will they get it that's another story.
once again i can't stress enough my appreciation for everyone's input.
thanks,
vq
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