WB-67 is combination truck Interstate semitrailer (WB-67) with sizes 13.5H, 8.5W, 73.5L and AFAIK , is used for geometric desing of highways ( Turning radius , etc) .
You are expected to look AASHTO Standard Spec. design truck loadings.
According to the grace of God which is given
unto me, as a wise masterbuilder, I have laid the foundation, and another buildeth thereon. . . .
I Corinthians 3:10