problem description
title="Beam Sample Problem with a Load Range"
nodes=3 elements=2

analysis parameters
nodes=[1] dofs=[Ty]
start=100 stop=1000 step=100
input-dof=Ty input-node=1

nodes
1  x=0   y=0 z=0 constraint=free
2  x=240 y=0 z=0 constraint=roller
3  x=480 y=0 z=0 constraint=fixed

beam elements
1  nodes=[1,2] material=steel
2  nodes=[2,3]

material properties
steel E=30e6 A=10 Ix=100

constraints
fixed  Tx=c Ty=c Rz=c
free   Tx=u Ty=u Rz=u
roller Tx=u Ty=c Rz=u

end