A beam that is part of a rigid frame has end moments and mid-span moments for dead, live, and earthquake loads shown below. Determine the governing load combination for both negative and positive moments at the ends and mid-span of the beam. Earthquake load can act in either direction, generating both negative and positive moments in the beam.
End Moments (ft-kip) Mid-Span Moments (ft-kip)
Dead Load -180 +90
Live Load -150 +150
Earthquake ±80 0