Plastic Modules Z with two different Fy
Plastic Modules Z with two different Fy
(OP)
For a given build up section with different Fy for each plate , I have the following questions:
1- To calc. PNA , The area * Fy above PNA = area * Fy below PNA.
2- To Calc Z ,sum off all (individual area* (distance form CG of each elemant to PNA))above and below the the PNA.
3- Mp = Z * Fy ( Fy= 50 ksi or 36 ksi based on the element location in the build up section)
Is this correct?
1- To calc. PNA , The area * Fy above PNA = area * Fy below PNA.
2- To Calc Z ,sum off all (individual area* (distance form CG of each elemant to PNA))above and below the the PNA.
3- Mp = Z * Fy ( Fy= 50 ksi or 36 ksi based on the element location in the build up section)
Is this correct?






RE: Plastic Modules Z with two different Fy
RE: Plastic Modules Z with two different Fy
"sum of all the moments (of forces) about PNA"
RE: Plastic Modules Z with two different Fy
to check the size
RE: Plastic Modules Z with two different Fy
Mp=Z*Fy , no?
RE: Plastic Modules Z with two different Fy
Simplify, multiply the area of the tee by 36/50 to transform it to 50ksi steel.
Can you place a neutral axis so that the compressive force equals the tensile force, and, the moment above the neutral axis equals the moment below? do you have to?
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: Plastic Modules Z with two different Fy
RE: Plastic Modules Z with two different Fy
RE: Plastic Modules Z with two different Fy
I have found PNA and the C=T (area * FY 50 or Area*36) based on the material.
Mn= C * d1 + T1 * d2 + T2 * d2
The PNA is in the web of the wide flange beam
C= 50 * A (the tee above the PNA part of upper W shape)
T1= 50 * A ( the tee below the PNA- part of the lower W shape)
T2= 36 * A ( the WT reinforcing with FY = 36 KSI)
d1= distance from CG to PNA of the element(upper portion of W shape0
d2= distance from CG to PNA of the elemant (lower portion of PNA)
d3 = distance from CG ot the WT reinforcing to PNA
Is this correct
Thanks to all
RE: Plastic Modules Z with two different Fy
i'd start with an elastic (linear) bending stress and see which yield is reached first. i think you can continue the analysis assuming a perfectly elastic plastic material (stress doesn't exceed yield) and you have to recalc the NA position (to maintain zero net force).
RE: Plastic Modules Z with two different Fy
RE: Plastic Modules Z with two different Fy