Of course you can, the question is whether or not you should. For the most part tortoises are solitary creatures. Russians especially so, they are loners by nature. I wouldn't do it personally.
Housing 2 different species together, even if their requirements are very similar, is generally a bad idea. They may carry and be susceptible to different pathogens and/or parasites - you could end up losing all of them (worst case scenario).
Both kinds are also very territorial, there likely would be fighting. I have 3 Russians, and one of them has to live in his own enclosure because he bullies the other 2. I have a Greek, and we keep him in a different room altogether.
In the end, of course, it is your decision, but I'd advise strongly against it...
pan1k said:
Can i house both a Hermanns and Russian Tort in the same enclosure? Compatible?
You can, but that may not be best. Were I to do so and were I to have only those two, I would select two females. If either is male, there would be a strong chance of harassment. If both are male, it is likely to be a never-ending cage match.
Along with the above reasons, in reality, if kept correctly, the Hermann's subspecies and Russian tortoises have some different captive care requirements.