Seismic Forces eccentricities X & Y directions

[Mohammed_Ata]

When i define seismic analysis type (equivalent lateral force method) , i want to define eccenticities in +X , -X direction with   eccentriciies  e=+5% & e=-5%

RSA should give me 4 cases :

1-  +X with e = +5%
2-  +X with e = -5%
1-  -X  with e = +5%
2-  -X  with e = -5%

but after determining the parameters of this , RSA defines also Y-direction .

This is shown in the screenshot , please see the cas name " ECC X-direction Y " , i only define x-direction !

[dimogrec · Accepted solution]

Mohammed, click on "Directions and Combinations" tab (it's over the "Definition of eccentrities" see left part of your image.) and change Direction Y from 1 to 0.

[Mohammed_Ata]

Thank you for reply , its ok .

In my Egyptian code , i should define Direction of forces with e = 5% and also -5 % in diection +X and also -X , then i have 4 cases for X-Direction and also 4 for Y-Direction !

do i have to define seismic analysis 4 times ? or there is a method to define all cases for once ?

thanks in advance .

[dimogrec]

In my previous answer I thought you needed only seismic force in X direction. (That's why I wrote you to set 0 value at Y direction)

In your image you have set ecc only in X direction, so Robot generates X and Y seismic cases with ecc in X (+X and -X)

If you set also eccentricity Y you will have all the seismic cases with their eccentricity by once (10 in total. 2 of them without eccentricity (seismic X , seismicY) and 8 with eccentricity)

Now I'm not familiar with your code,so I don't know if you have to combine them (for example SeismicX+0.3SeismicY+...)...