Topocad Tunnel Cross Section File
Adtolla SE creates programs that are used for Surveying and Mapping one such program is Topocad, this is a package that is used for Computer Aided Design from the field survey stage up to the finished designs or maps.
Files used for cross sections of tunnels in Topocad have the .ttu file extension
How to open .ttu files?
Software to open .ttu files
What are .ttu files