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Eartquake analysis
Hi
When I was going through few research articles related to earthquake analysis, they say: A compuetr code was developed where in which the eartquake input will be in either accelerogram or a displacement time history, digitized in in the appropriate format. What does it mean? Doest it mean that in studying simulation of seismic analysis we need to load that code as input? How to get an idea about that codes? Where to get? How to use?
Please help.........
Thanks in advance........
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Take a look at
Take a look at this
http://opensees.berkeley.edu/index.php
Might be what you were mentioning.
Yes........good response. It
Yes........good response. It is usefull for me..Thanks a lot
The same I was expecting
The same I was expecting using MATLAB.........
FEM
Hi all.........
I am working on Sloshing problem. I was going through one journal on Sloshing. Here in the problem FEM and BEM are both combined and applied. Liquid in cylindrical tank is discretized using FEM. And to evaluate the sloshing pressure and displacement BEM is applied. In BEM only those nodes which are on the surface(free surface and surface of liquid in contact with walls of cylinder) are considered. For dynamic analysis of this problem one needs to calculate free surface mass matrix and surface stiffness matrix. The matrix is given as follows:
M = (1/g)∑Mm ; where sum is from 1 to n, the number of free surface elements.
Mm is element mass matrix
And is given by Mm =∫ NTmN mds Integration is over EB2
where EB2 is the free surface elements areas and 'T' represents the transpose of the matrix.
Liquid is in cylinder and axisymmetric case is considered. For free surface two nodes i and j are considered. And:
r = local co-ordinates for free surface boundary element
R(r) = radius to any point r between node i and j
L = length of the elements
Transformations are written as:
R(r) = [ 1-r/L r/L] EQ(2)
ds = R(r)drdθ EQ(3)
thus N = [ 1-r/L r/L]cosθ EQ(4)
on substituting Eq(3) and EQ(4) in to EQ(1), we get
Mm = ∫({1-r/L r/L}T[ 1-r/L r/L ]R(r)dr EQ(5)
where Integration is from 0 to L;
Well now my problem is how we can evaluate the integral in EQ(5). The first two matrices can be multiplied to get 2X2 matrix, but later , on substituting R(r) the matrices are not compatible for multiplication….....
Please help I am struck up with this problem since a month. I am new to FEM. Trying to learn.
Thanks in advance
Inspiration and genius--one and the same. _______________________________________ http://sites.google.com/site/kolukulasivasrinivas/ ---------------------------------------------------------------------- Siva Srinivas Kolukula Junior Research Fellow