Unit conversion
Unit conversion
(OP)
Hi
I have a problem. I am modelling a concrete shell in SAP2000
I did it in (Tn, m) units; I have a moment resultant as follows:
"1.0373" I supouse (Tn-m)/m; when I convert this to (Kg,cm) I get "1037.3"
Didn't I have to find 1.0373*1000*100 (Kg-cm)/m.??
What exactly means, I really cannot figure it out.
Thank you for your time.
Regards.
I have a problem. I am modelling a concrete shell in SAP2000
I did it in (Tn, m) units; I have a moment resultant as follows:
"1.0373" I supouse (Tn-m)/m; when I convert this to (Kg,cm) I get "1037.3"
Didn't I have to find 1.0373*1000*100 (Kg-cm)/m.??
What exactly means, I really cannot figure it out.
Thank you for your time.
Regards.






RE: Unit conversion
If the units are kilogram-force and cm, then the moment should be given in kg-cm/cm
1.0373(tn-m/m)*1000*100/100 = 1037.3 kg-cm/cm
RE: Unit conversion
RE: Unit conversion
There is an unit kilogram force and the value is the same as the mass so the constant "g" is not missing.
RE: Unit conversion
[Tn]*[m]/[m]=[Tn]. But this is not a measurement unit for the moment. I can't understand what kind of distributed moment is this. My opinion is to consider the moment in Tn*m only, not in Tn*m/m.
Florian Smochina
RE: Unit conversion
If your moment is a moment per unit width of shell, as you have concluded, then you are starting with tonne*metres/metre. That is exactly the same as tonne*cm/cm, and the conversion to 1037.3 has given you kgf*cm/cm. (Essentially most formulae for moments in slabs and shells give you moments as force*length/length, and boil down to moments in units of force only).
ie the conversion result is in consistent units of kgf and cm.
If you want to mix your units of length, and work with kgf*cm/metre you must multiply by 1000 to get 1037300.
RE: Unit conversion
I think S2K transforms all the units, as well as:
internal forces (Tn/m) to (Kg/cm)
resultant moments (Tn*m/m) to (Kg*cm/cm)
and you maybe need (Kg*cm /m) to design so, it is ok
what austim says, but you must multiply by 100 to get
103730, because de Ton to Kg is already converted.
RE: Unit conversion
My only excuse is that in Aus no-one uses cm, and all conversions are from mm, so my 1000 went straight in out of habit
RE: Unit conversion
Therefore the second post by dlew is right.
RE: Unit conversion
Any way, that's how it should have been presented:
1.0373 Tn-m/m X 1000kg/Tn X 100cm/m X 1m/100cm=
1037.3 Kg-cm/cm
The meaning to the result is that the moment =
1037.3 Kg-cm per lineal centimeter
The lineal centimeter could be along the circumference of the shell that you are addressing. It could also be along the straigth length of a seam. I Just dont know because you did not state where that moment was calculated.
RE: Unit conversion
http://www.joshmadison.com/software/
josh@joshmadison.com
you'll find all quantities (masse, moment, pressure, ....)