4-lane to 2-lane junction
Posted: Mon Dec 11, 2017 11:39 pm
I want to upgrade my 'backbone' to 4 lanes (2 each direction) while keeping the rest of the network on 2 lane track. I guess I could take any odd 4-lane intersection and merge/split the ends, but I thought I would try my hand at designing one. I started from the "traditional" junction in the stickied intersections thread, and turned the sideways branches into 2 lane. I also wanted to change the spacing: the sideways branches are spaced 9 apart (leaving room for two rail in between with 2 block spacing, which is my normal distance between stations) and the middle lanes of the 4 lane track are spaced 8 apart (leaving room for a lane changer in between).
Note that not all lanes are connected: the outer tracks do the left turns, the inner track the right turns (it's left hand drive / LHD). So, to allow anywhere-to-anywhere connections I need to place lane changers between junctions.
This is my first real try to design a junction, so far I just copied good designs . So what I tried to make sure was (1) to have chain signals before each crossing and a normal signal at the exit points; and (2) that traffic that doesn't need to interfere doesn't interfere, i.e. opposing right turns can go simultaneously and the straight lanes in the same direction are all isolated from each other. I think those are the desired properties and that I managed to do this, but all feedback welcome!
Note that not all lanes are connected: the outer tracks do the left turns, the inner track the right turns (it's left hand drive / LHD). So, to allow anywhere-to-anywhere connections I need to place lane changers between junctions.
This is my first real try to design a junction, so far I just copied good designs . So what I tried to make sure was (1) to have chain signals before each crossing and a normal signal at the exit points; and (2) that traffic that doesn't need to interfere doesn't interfere, i.e. opposing right turns can go simultaneously and the straight lanes in the same direction are all isolated from each other. I think those are the desired properties and that I managed to do this, but all feedback welcome!
image with lane changer and distances
image with rail blocks
blueprint