In-situ stiffness and mass
post
The question here is how many methods available to evaluate in-situ
stiffness and mass of well constructed structres and solids. Stiffness is
the most important property to analyze structural response. We use
theoretical expressions of stiffness and mass to simulate and design
structures. The problem is, after structure has been well constructed in
position, what an actual stiffness (or mass) is. Theoretical expression of
stiffness fails to answer the question. We need a method to evaluate in-situ
stiffness and mass.
Furthermore, material could be deteriorated, and structure could be damaged.
How could we know, in advance, if an aging or repaired structure is safe to
a forseen impact or use. We need to evaluate in-situ stiffness and mass.
The site, www.equation.com, presents a tool, code name JUNE5, for evaulation
of in-situ stiffness and mass. As stated previously, how many methods are
available (or proposed) for evaluation of in-situ stiffness and mass? Could
we discuss the issue? Thank you.
Anonymous #1
Greg Locock
> x-posting.
>
> The question here is how many methods available to evaluate in-situ
> stiffness and mass of well constructed structres and solids.
1 : Experimental modal analysis
Cheers
Greg Locock
Anonymous #1
"Greg Locock" <gregl...@yahoo.com.au> wrote in message
news:Xns9A7E6975E65B877...@211.29.133.50...
>
> Cheers
>
> Greg Locock
Are there any links to have more information on the analysis?
Kind Regards
Greg Locock
Anonymous #1
>
>
> 1 : Experimental modal analysis
>
> Cheers
>
> Greg Locock
Thanx for the response.
I googled it, and I did find applications of experimental modal analysis to
nondestructive evaluation, i.e., an attempt to locate damages or others.
However, I could not find anything that evaluates in-situ [K] and [M] of a
well-constructed structure. If you have links, is it possible to post them?
Thanks.
Anony
>
> wiki
Links to evaluation of in-situ stiffness and mass are welcome. Thank you.
It seems Equation Solution (http://www.Equation.com) jumps ahead. The
following is a link for evaluation of in-situ stiffness and mass
http://www.equation.com/servlet/equation.cmd?call=june5
Greg Locock
Can you explain why the method you propose is superior to experimental
modal analysis?
Anony
>
> Can you explain why the method you propose is superior to experimental
> modal analysis?
>
You did not post a specific question. I am not sure if I provide the answer
you are looking for.
Based on the links I googled on the internet, experimental modal analysis
compares test results to check if the structural properties have a
significant change so as to locate damages. The mothod I introduce evaluates
in-situ stiffness and mass. It seems there is no other method that could
evaluate in-situ stiffness and mass. Stiffness and mass, we apply to analyze
structures, are calculated by theoretical formulation. The actual stiffness
and mass are different from the theoretical expression. Material could be
deteriorated or aging, and structure could be damaged. Apparently, we need
in-situ stiffness and mass to monitor structural condition. However, we
never developed a method that could evaluate in-situ stiffness and mass. The
method I introduce is for evaluation of in-situ stiffness and mass.
Experimental modal analysis is proposed to locate damages by comparing test
results. What is the definition of damage? A change in structural property
is not necessary a damage. Can we say a structure is damaged if the
structure can safely respond to all foreseen impacts, even the structure has
a change in structural properties? If we have in-situ stiffness and mass,
that could be evaluated at any time when necessary, to analyze a structure,
we can see in advance whether a structure is safe to a foreseen use or
impact.
As stated at the beginning, I am not sure which specific question you ask.
In-situ stiffness and mass have other applicatins.
Is it the time for us to consider how to evaluate in-situ stiffness and
mass? The following is a link that introces a method for evaluation of