huangyhg

contract issues - structural steel connection design in the
i am located in the midwest (new madrid fault zone).....an area that is relatively new to serious seismic design. on several projects we have fallen into the scope of the aisc seismic provisions. because our industry here is set up in a way that is not conducive for the eor to design lateral force resisting system connections, the connection design responsibility is forwarded on to the fabricator. bottom line, the eor is not given enough time and/or fee to do connection design. it it becoming more and more common that fabricators are coming back during the project demanding more money (hundreds of thousands of dollars) because the connections geomectrically dont work, they didnt budget large connections, or they just make up excuses to cover their losses.
we have tried several ways to make it clear to the fabricators that the connections will be larger than normal, and that the seismic provisions are to be followed. but it still ends up that the fabricator claims that he/she cannot properly bid the connections because it takes the technical experience of an engineer to do so.
has anyone else run into this problem and how have you remedied it? anything to put on the contract documents? any good published information out there? i assume this problem extends over to the east coast.
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i perform this exact connection design for fabricators. the ones who have done these types of jobs before know what to expect and bid it accordingly. the ones that don't research the matter, discuss it with us, and determine how much to include in their bid for connection design (usually we submit to them a bid for connection design, with estimated gusset plate thicknesses, brace reinforcement plates, etc).
a good set of drawings will indicate the seismic requirements. they'll also show details with large gusset plates, bend lines, brace reinforcement, etc. an experienced fabricator and connection engineer should be able to bid these projects accurately.
as far as communicating this to the fabricator, the only thing i can think of is to make specific mention of the seismic requirements and show some details that truly represent the larger connections that will be required.
similar issues in my area (oklahoma). however, i've increased fees as needed to cover the connection designs and seismic analsyis. explained to clients that code changes for seismic design increased my scope of work and it takes more effort to do the engineering. told several clients that i can do the design now or they can pay more to have the fabricator pay another engineer to do work i have to review. some grumbling at first until they realized they would be paying two engineers to essentially do the work of one. it might take time, but you should be able to convince clients to give you the time and fee to do connection designs.
unfortunately we are the little e in an a/e firm, therefore its much more difficult to convey these structural issues to the clients. the architects (ones who usually deal with clients) tend to agree to anything and everything the clients demand...including outrageous deadlines and barebone fees. telling them that it will take the engineers more time and money will be nearly impossible. i think the only way to change the situation is for me to quit and change companies
it feels like the more typical connection details we put on the drawing, the more problems we get...the fabricators tend to look at them as set in stone. when the fabricator's engineer turns around and tells them the connection cant work exactly as the detail shows it, they proceed with a change order.
you have to make the point that the detail is schematic only, just to show intent, and that connection design shall be performed by the fabricator and sealed by a licensed engineer, etc......
the beefed-up seismic connections would be quite a shock to the contractor/fabricator/detailer if they weren't shown on the drawings, so to keep from surprising anyone (and incurring extra costs), i think you have to show some sort of typical detail.
doing connection design, we see drawings from engineers all over the country. this is pretty standard practice, and an experienced fabricator shouldn't be surprised by this.
loui1....one of the most significant problems we face today as engineers is the erosion of respect for what we do. part of this comes from others not understanding what we do and its importance in the whole scheme of things, but most of it comes from within. we are our own worst enemy.
i would suggest that you take a stand with your firm and get what's necessary to do a proper design. you've already laid out the case (change orders/claims). if they are unwilling to listen, then yes, it's time for you to move on. you're in a situation that could easily attempt to compromise your integrity and that of the engineering profession.
i dont think that we are our own worst enemy. i feel the problem lies in the fact we have no unified entity representing the profession that takes a strong enough stand on certain issues. it feels like we're a broken flock of sheep meandering around the contryside. the profession is asking us to act as individuals to change the industry, which is just ludicrus when you look at our salaries. i know i dont have the monetary luxury of risking my job. what ever happened to "strength in numbers"? each state has its own structural engineers group that kindof tries to organize us locally but doesnt always have the necessary clout, and asce seems to be too broad to represent us well....the reason why i toss the weekly asce "come join us for $200" mailing.
that's beside the point. i was just looking for ideas of what to put on the contract documents to avoid these change orders. it appears we're doing all that we can do at the moment in the current situation.
as far as documents go, you would have to put on all forces that the fabricator is to design to and combinations, thereof. in addition, you should clearly note that the fabricator is responsible for the design and procurement of a registered engineer to undertake the connection design and that no additional fees will be entertained in the design of same. you should also show typical details of the various types of connections required for the various conditions.
as far as being our own worst enemies, i think the thought comes from the idea that i can design something for a cheaper price than ron can and i'm prepared to do this (not serious, ron). this, in my opinion, has caused the decline in the quality of trades available, too; contractors cannot afford to hire quality people. in our environs, a real estate agent can make more money selling a building than the engineer that designed the building.
dik
i think it is irresponsible for any eor to pass on the lateral design of a building to the fabricator. the lateral bracing system of a building involves multipe elements, metal deck, elevator shafts, braced frames, rigid frames and foundations. also the building geometry has a huge effect on the bracing systems.
when a job gets to a fabricator the above items are already established. this may result in a geometry which may makes it difficult or almost impossible to design the connections. when a fabricator encounters this problem he doesn't have the option of adding another frame, increasing the column or beam size, ect.
unless the eor has atleast done some preliminary designs on the critical connections to verify that they workable and reasonable, he may be creating a problem that can't be solved by the fabricator. a problem which could be avoided if anticipated by the engineer, who can adjust elements before the job is bid.
a simple example is an engineer who decides to pin the base of all columns. i have dealt with wood jobs where the engineer designed all column bases as pins and assumed that the wood beams and columns where acting as rigid frames to resist the lateral load. on one job i indicated to the engineer that i could develop fixity at the top of the columns but that the architect and owner would not be happy with the amount of steel required to solve the problem.

rarswc, we're not passing on the "lateral design of a building" to the fabricator. the lateral force resisiting system should always be called out on the plans. we're talking about the design of connections of these elements. if you've ever gone through the design of a seismic brace connection, you know it's quite a lengthy process, and the cost to do that is rarely included in the engineer of record's fee.
the lateral design is not just the members. the lateral design is also the connections of those members.
indeed, i recall edward phrang once spoke at a seminar on the hyatt regency disaster in kansas city in the 70's and his concluding remarks were something like: "we engineeers need to get past this notion that we are designers of frame members that just happen to be connected. we should rather think of our structures as a multitude of connections linked together by

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