There are technologies for sale, especially in Germany, to drill holes in the walls of a cellar, and inject into the concrete or masonry a liquid, such as Sodium Silicate
The manufacturers promise these chemicals will make walls waterproof and sell it as damp-proofing for cellars and the like.
Most of these products are used in combination with other methods, like plastering the wall. Hence, one can not see the individual effect. Some people complain that after a few years the injections must be repeated. Some manufacturers explain that the user can see the benefits only after a few years.
However I have not found any independent and trustworthy publications supporting the injection method.
It seems this method is heavily advertised in Germany, but rather unknown in most other countries.
I do not know if it is fair to write the companies' names here, hence I link to the German Wikipedia article describing the method.
Have there been any scientific investigations into the effectiveness of liquid-injection damp-proofing?
Advertised German injection products are for example:
http://www.mem.de/projekte/trockene_haeuser/aufsteigende_feuchtigkeit.html (using potassium silicate waterglas)
Remmers KIESOL waterproofing