Recent content by DENSAL55

masomenos Using special joint such we have describe by giving the offsets for joints one by one, for this purpose need a lot of time. Especialy when we have a complex or a big structure.

masomenos Say "Note that you don't have to divide the frame, you can draw special joints using the 'snap to line' or offset options" I do not understand ?

To confirm what i said before, you can see that Etabs use the Story shears value to calculate oveturning moment Mx and My. at differents levels and at the base of the structure.this overall moments is equivalents in value to those you obtain by the equivalent static case using story shears.

It's what i say .A combination or SRSS give always an absolute value and we can't use this result for a calculation of slabe fondation or beam fondation it can't give the overturning effect . So we can use an equivalent static model by using story shears applied as static forces.

it's depend on the meshing of your shell element.If the number of elemnts shell is high the distrubution is more correct.You must divide your beam into the same number of elements as your shell elements.So it work together.

To impose a displacement to some selected nodes? Select joint go to assign > joint load >displacement.

There is anothere way to solve this problem.Make spectrale analysis then take sheare story result and there position, and make a static analysis with the previous sheare story as static force in the new analysis at there respective position, the reaction given at the base of the structure is...

exporting spectral analysis results from Etabs to Safe for slab foundation analysis or beam foundations analysis has no sens because results given by spectral analysis are always in absolute value this means that they are always positive or if multiply by -1 always negative.And by this way it...

The local axes shown is the default one for the input section properties you have defined.If you want anothere one you must select the frames you want to change the direction > assign >local axe then you input the new value of angle.

Yes it will calculate the self weight of all object if the option in mass source are checked.

you can take reactions at supports which are multiply by (-1) and apply them at there position on the beam.the value of spring stiffness which modelise soil must be multiply by the width of fondation (beam). the precision of calcul depend on the number of division of beam. anothere way is to...

- x3 represente the variation of thickness of slab from midplan of slab to the point where the stress is calculated .

in the case of slab it is not so simple, because we have many type of stress S11=F11/th-(12*M11/thb^3)*x3. S22=F22/th-(12*M22/thb^3)*x3. S12=F12/th-(12*M12/thb^3)*x3 etc... x3 represente the variation of thickness of slab. to obtain M11,M22 etc... we must integrate the stress...

See in "CSI Analysis Reference Manual Page 144 " *Internal Force and Stress Output* The Shell element internal forces (also called stress resultants) are the forces and moments that result from integrating the stresses over the element thickness.....etc

... and for point support we must multiply the value by the two plane dimenssion and we have force/lenght.