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RE: ASCE 07

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Bill,

I believe that we are witnessing a knee-jerk response by adding everything
to the code that can be calculated in a new way.  The safety of the
constructed product is the only criteria that should matter to the design
engineer.  As I said before, if you want to write a book on what you think
is a better way to analyze or design something you are welcome to do so and
it may be useful to those who read it.  But that is your way and not
necessarily the way other engineers view the problem. That type of material
should not be in the code if it does not improve safety by correcting a
problem that actually exists other than in the imagination of the writer.

Computers calculate numbers - they do not design structures; and, the
methods that they use to calculate are what the programmers put into them.
The building code is being crammed with factors and numbers that can be
easily utilized by your computer but which do not necessarily lead to a
safer structure. A 99.99% correct calculation on 50% of the actual problem
is still only 50%. Do most of the code changes lead to a better
understanding of the entire set of conditions that the structure encounters
or do they just lead to nicer calculations of that part that is being
considered?  Is it very important that you use an R factor of 3.5 rather
than 4.0?  The computer can use either but does that result in a safer
structure?

There was a quotation on Albert Einstein's desk that read "Not everything
that can be counted counts, and not everything that counts can be counted"
Unless the engineer is cognizant and familiar with what happens to actual
constructed structures in the field, they can be easily led to think that a
new, more complicated, method of calculation is that which is most
important. It is not.

My concern is that the grossly expanded size and complexity of the building
code makes it appear more important to count, to ever increasing accuracy,
all of the clever ways of counting that are added to it, while losing sight
of whether that increased counting actually improves the constructed
structure.

Research is important and it has its proper place.  However, the building
code should not be viewed as a research tool, and if it is made into one, it
will be useless as to its real intent of ensuring safer structures through
design by practicing engineers.

That is why I asked those questions.

Richard Hess, S.E.

-----Original Message-----
From: Bill Polhemus [mailto:bill(--nospam--at)polhemus.cc] 
Sent: Monday, July 11, 2011 11:21 AM
To: <seaint(--nospam--at)seaint.org>
Subject: Re: ASCE 07

Richard, all I'm suggesting is that we estimate forces for our work.
Certainly we may do so in any number of ways, but we've agreed (or at least
conceded) that we're going to adhere to this particular standard. 

I had a professor who had strong opinions about analysis and design some of
which were at odds with the conventional wisdom - including what was
published in the design codes. In many instances his objections were strong
enough that he felt compelled to do things differently in his own work. 

I'm not sure what the ramifications are. Certainly we cannot ignore the
potential for involuntary interaction with the distinguished members of our
fine legal community. 

I suppose that if you believe some other methodology to be more correct, or
sufficiently rigorous while at the same time easier to use, one might feel
justified in going that direction.  

My own opinion is that things are certainly much easier to implement in this
age of cheap and powerful computing. Simple hand methods are always welcome
as a sanity check. 

I'm not sure that we are really so constrained in our procedures by the
continued advancement of knowledge that a wholesale rebellion is warranted,
however. I think the knee-jerk response AGAINST code revisions is no more
rational than comprehensive revision "just because we can."

William L. Polhemus, Jr. P.E.
Via iPhone 4

On Jul 11, 2011, at 12:49 PM, "Richard Hess" <RLHess(--nospam--at)HessEng.com> wrote:

> Hello Bill,
> 
> I believe that "the way things are done" should refer to the constructed
> structure, not to some clever new research into the "nature" of a force.
> 
> Richard Hess, S.E.
> 
> -----Original Message-----
> From: Bill Polhemus [mailto:bill(--nospam--at)polhemus.cc] 
> Sent: Thursday, July 07, 2011 11:49 AM
> To: <seaint(--nospam--at)seaint.org>
> Subject: Re: ASCE 07
> 
> ASCE 7 is not a materials design code. It is agnostic regarding
definitions
> of things like "failure."
> 
> It is a code that defines the criteria for estimating or approximating
> design-level loads. The changes incorporate the progression of
understanding
> of the loading phenomenon. 
> 
> For example, there has been a lot of research into the nature of how wind
> interacts with the surfaces of bodies to generate loads on those surfaces.
> ASCE 7-10 incorporates the more recent understanding. 
> 
> EDITORIAL NOTE: I have always been somewhat at a loss to explain why so
many
> of my colleagues resist and are quite frankly militant against changes to
> the way things are done. 
> 
> I suppose you could use the old ANSI A58.1 code for loading if it makes
you
> feel more comfortable...as long as "nothing bad happens."
> 
> And I guess you could insist on having all your kids' tonsils removed as
> well. 
> 
> William L. Polhemus, Jr. P.E.
> Via iPhone 4
> 
> On Jul 7, 2011, at 1:26 PM, "Richard Hess" <RLHess(--nospam--at)HessEng.com> wrote:
> 
>> Questions:    
>> 
>> 1.  How many of the changes are due to actual failures in the field of
>> structures properly designed by previous editions?
> 
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