Recent content by Alireza1945

For an unconfined aquifer , we have this pde for the water table position , of course after making the Boussinesq somehow linear : ∂²(h²)∕∂x² + ∂²(h²)∕∂y² = (2s/k ) ∂h/∂t - 2N/k N and K and S are constants . would u tell me what type mathematically it is ? this equation , in respect to h^2...

How about editing and importing from Excel ?! maybe im confusing Etabs with Sap...cause i learned Sap mostly and been told Etabs is the simple one .... anyhow...i liked the way i could bring anything from Excel into SAP especially for long lasting entries :)

I even cannot show or Edit load combos in a chart or Excel....what is with this version ?!!

I have a problem with Show Table command in Etabs 2015 , it is not like older versions for me... i mean i cant find the option for show table....like we could choose load combos and selection only and .... where is it in Etabs 2015 ? help me out guys ~

oh , by the way , for frame transformation to spring , i know nothing about it , i have to read about it first , tnx for mentioning ))

first , thanks for your attention ! and time ! umm , as the specifications tell me , in the NS direction my lateral bearing system is moment frame , yeah , but that is not the case for the EW directiom , i assumed that bracing system will act on that direction only , and frame is simple ...

yeah , i am doing hand cal instead of letting Etabs ... , i like to understand things , i really have no experience , okay , i will attach the actual plan here : http://files.engineering.com/getfile.aspx?folder=2bdfc061-b7e8-4b56-bb46-1948ba98fb61&file=Untitled.jpg

jayrod12@ thanks , i neglected it so far , but it produces a great deal of eccentricity , and torsion , as u said , KootK@ i dont get you , by fictional frames ,, i mean , i only need to calculate in NS direction , and in that direction under E and F we have only one column , do u mean i add...

OKey-doke , and yeah , this question is well defined under seismology , i dont know why .... here is the pic : http://files.engineering.com/getfile.aspx?folder=afce5ffd-5e11-4695-9125-9feeb14cc4ce&file=asa.png

I have posted same problem in Seismology department here , but i think i explained in a not clear way , i got no reply ,, well , the problem is , i am calculating lateral stiffness for frames , steel frames , and to reach story lateral stiffness and CR point . problem is , i have an oblique...

For calculating the center of rigidity of a floor system , i know that i have to first find the rigidity of frames in horizontal and vertical direction , but now i am confronted with something that im not capable to understand and calculate , i will attach the columns plan here in this post ...

Yeah , that is a real good command , useful , i will check it with masspprop too , again tnx )

Thank you , for your guide and help . i really needed to know if surplus calculations are wrong are just to be more accurate , i was in doubt , , and by surplus i meant walls )) okey-doke !

you know , when i talk with friends , they just tell me that , forget about walls , and this half height difference in first floor , they can be neglected , no big difference in CM happens , ... but i dont like to neglect , and about these partitions , why is that they say use uniform load ...

I know it seems very elementary , but i have problem and doubts , well i want to know , when im going to calculate center of mass in each floor , without any software , should i calculate the weight of walls ? walls at perimeter and partitions ? and what about that half of the height of walls...