diamond interchange

[dav_1]

we have just started using tru-traffic software and I am configuring intersections for gps run. I imported
synchro file (csv) and all intersection information looks good except the diamond interchanges for our
I-95 NB/SB off ramps. The lane configurations are correct under the lanes tab for intersection information,
but under the timings tab it shows a different configuration. I tried to modify the timings window but, for example -
under timings tab - the SB off ramp shows a NB thru movement that I cannot remove - this movement is not shown on the
lanes configuration tab. I tried to recreate the file by deleting the two intersections and inserting two new intersections and manually configuring them to no avail. I do not understand why the timings tab and the lanes tab show different information -
Is there a step I am missing to make these two configurations match? I have attached the tru-traffic diagram file that contains
the imported synchro infrormation with no modifications to it. Any help with this is greatly appreciated.

Thanks -

David

[bullock]

Hi, David.

Would you post also the *.csv file that Synchro exported? This will help me understand what the timings should look like.

Tru-Traffic will often create a phantom through movement phase as a sort of placeholder to fill a ring's time gap corresponding to an exclusive turning movement phase in the other ring, so diamond interchange phasing can end up looking like split phasing. As long as this phantom phase isn't goofing up the splits or phase sequences of real movements, then you can ignore them, or set their corresponding splits to 0. Typically, this quirk is visible on the Timings page but not actually in the time-space diagram.

But in this case, from looking at the file you posted, it looks like Tru-Traffic may be compounding this quirk with an error or two, and I'd like to look a little deeper into that before commenting further. For that purpose, I requested the *.csv file as exported from Synchro.

Greg

[dav_1]

When I attach csv file the reply window says that extension csv is not allowed.

[bullock]

Oh! Thanks for reporting that. I just modified the forum settings, so it should now accept posting *.csv files. It seems that the default setting was to disallow those files.

[dav_1]

Please find the attached csv file - and let me know if you require more information.

David

[bullock]

Thank you, David.

The .csv file has no phase (protected or permitted) for the NBL at the I-95 NB off Ramp (#4181). Can you help me understand what's going on there?

Greg

[dav_1]

The NB ramp is configured with two protected left turns and a hot right. Same with the SB ramp, two protected lefts and a
hot right.

[bullock]

What's different, in the Synchro file, between the SBL and the NBL that might account for why the .csv file shows a protected phase for the SBL but not for the NBL?

[bullock]

Version 8.0.0.62, now available for download, seems to fix the problem.

Thank you for reporting the error.

Regards.
Greg