problem description
title="Truss Sample Problem (Logan ex. 3.10, p.101)" nodes=3 elements=2

nodes
1 x=0 y=0 constraint=fixed
2 x=30 y=0 constraint=free
3 x=60 y=0 

truss elements
1 nodes=[1,2] material=steel load=tri1
2 nodes=[2,3] material=steel load=tri2

material properties
steel a=2 e=30e6 

distributed loads
tri1 direction=parallel values=(1,-600) (2,-300)
tri2 direction=parallel values=(1,-300) (2,0)

constraints
fixed tx=c ty=c tz=c
free tx=u ty=c tz=c

end