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RE: Partially rigid connection design

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Dear Bills,

Thanks for your comments. I hope we hand-in-hand find practical solutions
for completing projects within given schedules and budgets.

On this very engineering list, I really do not like to go philosophical, but
there seems to be no choice left.

>I am not saying that good research is not a worthwhile endeavor. What I am
>saying is that I believe there are three elements/phases of engineering:
>
>1. The science of engineering-Testing, research, development of algorithms,
>etc.
>2. The art of engineering-Extrapolating the testing, research, etc. to "real
>world" problems
>3. The business of engineering-The act of performing the above within
>contractual budgets and schedules.


Well, given your definitions, I can claim I advocate your item 2, while
I watch for objectives in 3 for the sake of my client as long as my
professional responsiblity is not sacrificed for the budget and schedules. 

Bill, in my humble opinion, we, as engineers have to know the potential
technical problems that a simple but fast design may cause, and make our
client aware of significance of doing a more refined analysis/design
approach. Then present the facts about time,cost and risk issues involving
various design approaches to the client and give them the benefit of
choosing what they pay for and what they get. 

However, this is not easily achievable if we, ourselves, cannot appreciate
technical problems arising from simple and fast track designs, on one side
and facing, on the other side, the pressure from our client to finish the
job ASAP at the lowest cost. If we cannot convince ourselves that there is a
problem, and when we do not know how long it takes and what it takes to
solve it, spending a minute doing any thing beyond what a fast track design
seems nothing but waste of time and resourses. 

I do not suggest here that engineers must become researchers, and
investigate thouroughly before design and detail things, for projects would
never get completed. However, I think they should be aware of the results of
research and apply them in practice whenever applicable, rather than
regarding them as prure sience, i.e good food for thought but no practical
applications for years!.

As for our semi-rigid connections, many works have been done for years
(1936-now). There are various databases and programs available which can be
used by engineers today. I am not suggesting here that as of tomorrow we
must design all our frame with semi-rigid connections. One must justify the
time and costs involved, and know what is there to gain from making an extra
effort of design semi-rigid connections. Its design and use may be well
justified for some projects. My personal opinion is, a semi-rigid frame may
be a bit lighter, and cheaper than a regular frame. And I agree with you is
you say this may not overal justify its use, as it takes longer to design.
However, from seismic performance point of view, semi-rigids are more
reliable than rigid connections, and their analysis and design may well be
justified. 

Remember, our rigid conections are not 100% rigid either. In fact, the past
practice made them behave more like stiff-brittle connections! I hope we do
not design and detail our connections exactly the same way as we did before
Northridge EQ, just to complete the job within time and the budget! So,an
acceptable rigid connection must be carefully designed too.


>It would be irresponsible to be spending time on one element while being
>paid to do another. IMO, a lot of code documents appear that they were
>prepared ignoring the consequences of item 3.

Code requiremens have been prepared to ensure safety of public who has no
technical knowledge to check adequacy of engineers' designs. While public
does spend money and want the work done fast, must be made aware of the
risks through advice and opinion of knowledgable and caring engineers in
charge. 

We have duty to our clients to tell them what is good for them, what are the
risks, what are the costs and where they should expect us to spend their
money, becuase we have the technical knowledge. Then, they can choose
whatever they want us to do with their money.  Do I sound too honest! 

Best regards,


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                  |                                          |
                   \               Majid Sarraf             /
                    \             Ph.D Candidate           /
                     \   Department of Civil Engineering  /
                      |        University of Ottawa      |
                      |           Ottawa, Ontario        |
                      |            Canada K1N 6N5        |
                      |   Tel:(613) 562-5800 Ext. 6159   |
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