COMBTHSDB,<Xfile>,<Yfile>,<Zfile>,<Comb>
Combine three input element stress/force/moment history binary databases for X, Y and Z seismic input into a single database.
Xfile - full path name of the x direction binary database
Yfile - full path name of the y direction binary database
Zfile - full path name of the z direction binary database
Comb - full path name of combined direction binary database