column design -modulus problem

[egoze]

i am do a design for a column 

and a have a problen how to let robot take the young modulus of concrete and steel ? you can see in the pic ..

i have anther point 

why robot in design of column taking Bdns =1.0 every time 

and as you know sir it very importent factor in   design equation of  column results

i find it 0.50 and he took it 1.0 i need from him to calculated as what it is.  

thank you

egoze

 you can check the pic & file please

[Artur.Kosakowski]

The RC Design modules calculate values of E based on values of concrete resistance according to the formula from the selected RC design code. The parameters of steel are taken from the reinforcement bar database.

The live load you defined is the long term one with B-1 the same as the dead load

if you change your live load to the short term:

then

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[egoze]

hiiii 

thank you sir 

what do you mean by ..

The RC Design modules calculate values of E based on values of concrete resistance according to the formula from the selected RC design code..

so thee is no relation between the young modulus of concrete which i definef it from 

tools -job perefrance -materail ..etc

i difened it to be 24855.61 Mpa   not  26521.33 Mpa

 ok

now what is the furmula from where i got it  ? i use E = 4700*(fc`)^0.5

how can i change 26521.33 Mpa to be 24855.61 Mpa  

Can you show me how to to fixed it  ,or where can find the formule in robot   

thank you 

egoze

[Artur.Kosakowski]

For ACI 318

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[egoze]

excactly 

my problem  in this eqaution 4700(fc)^0.5   ...> 4700  or ( 4743.077  )  comes when we use wc=2300kg/cm2  which means evry times i conseder the wc to be 2300kg/cm2

thank you sir 🙂

i have still small point 

ise moment of inertia of steel in robot 

the formula of Ise

  i used 25 mm as main bar 

              10 mm as transfer 

              4 cm cover 

Regards

egoze

[Artur.Kosakowski · Accepted solution]

my problem  in this eqaution 4700(fc)^0.5   ...> 4700  or ( 4743.077  )  comes when we use wc=2300kg/cm2  which means evry times i conseder the wc to be 2300kg/cm2

Robot calculates Ec according to the yellow formula when wc is smaller than 160lb/ft3 and according to the red one when wc is larger than this value.

i have still small point 

ise moment of inertia of steel in robot 

the formula of Ise

  i used 25 mm as main bar 

              10 mm as transfer 

              4 cm cover 

Robot uses the exact positions of rebars. I the case as below the distance from the bottom edge to the middle rebar is 40 + 10 + 12.5 = 62.5mm whereas to the corner one is 55.6 + 12.5 = 67.1mm 

 If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[egoze]

thank you but i was asking for Ise  

[egoze]

hi 

robot is using eq (10-14)  to find  EI in ACI code

how robot fid Ise 

Thank you

Attachment

[egoze]

hi im looking to hear from you soon

thank you

egoze