Is that possible to create a virtual ground,for electrical purposes?
If you look at Wikipedia's page on Earthing Systems, You can see that Earth is usually just connected to Neutral at some point in the system. There are advantages and disadvantages to each system, involving different cost and levels of safety among other factors. 

The scheme it appears you have is either the "TT" or "IT" topology. Although off the top of my head, there is another one it could be that isn't listed on that page. I would consult an electrician who will either inspect the system, contact the electrical supplier for the area, or both, to determine the best course of action.