TI21 tc's under electrification

[brenners]

Hi their, Looking for a bit of info and was wondering if anyone could help. Im writing up a report and it involves TI21's. Im looking to find out how feasible it is to use TI21's in areas of AC electrification. I know they are traction immune but currently do not appear to be in use by Network Rail in these areas. I know their are issues with return bonds and wrong side failures, and lineside structures would be need to be seperately earthed. Also impedance bonds would be needed for traction return. Just wondering if anyone knew how feasible it would be to use TI21's in areas of electrification or where they are currently used under electrification.

Cheers

brendan