same thing, l-c ladder network, but with distrubted component values different to match the impedance and propagation constant. Also some transmission lines has dispersion, so you would need a frequency dependedn L and C for those cases.
each propagation mode is a new way for energy to get from point A to point B. I have seem multimode transmission lines represented by a transformaer coupling mechanism, and individual L-C networks for each mode of propagation placed in parallel.