- #1

CallumTheMan

- 5

- 0

## Homework Statement

Stress = 320 MPa

Max Elastic Moment = Stress*Z

Max Plastic Moment = Stress*S

Solve the maximum moments and compare the % increase

Beam is an I beam with dimensions: (b and d)

Top Flange = 25*10

web = 10*180

Bottom Flange = 200*8

## Homework Equations

see above

## The Attempt at a Solution

Ybar elastic = 63.3mm

Ybay plas = 30.5mm

Ix=1.687*10^7

Zx = 266501.107

S = 191868.75

S is lower than Zx and this makes the plastic M smaller than M elastic. How is that possible?

S= (25*10*162.5)+(10*157.5*67.5)+(22.5*10*11.25)+(200*8*26.5) this is the only value I had to manually generate without computer aid so there must be an error here?

Can't seem to find out what's going wrong.