Bridge support suggestion

[Dan]

Can someone make graphics to match my bridges, they look a little out of place:

[Wolf01]

Can someone make graphics to match my bridges, they look a little out of place:

questions:
1. what are those signs in the "ramp" of bridges?
2. is possible to make the selection of bridges in relation of the height like the actual relation of the width? 4 example, brown bridges max 1 square height, grey bridges max 2 squares height and yellow bridges 3 and up squares height