Dead Load Moment for Steel Beam Reinforcement

[delagina]

Can someone explain the logic why we still need to calculate Moment for Dead Load only for Steel Beam Reinforcement?

Thanks,

 

[BAretired]

You don't need to. You need to know where the maximum DL + LL moments are.

You can do that by considering DL effects on all spans, then considering LL on each span and combining to produce the worst case scenario for each point.

Or you can consider DL plus patterned LL to produce the worst effect at any given point.

BA

 

[Lion06]

It depends on the approach. If you're not jacking the system, then you need to calc the DL only moments so that you can superimpose the stresses (DL only based on unreinforced section + LL and SDL based on reinforced section) to make sure the allowable stresses are acceptable.

If you're jacking the system to take out the DL stresses, then you don't need to worry about it.