and restore what has been lost:One of the most important thing to remember when doing conservation work is that every thing we do must be possible to undo should a better technique arise. A) Restoration:All walls need to be consolidated. This is a difficult task since we must be able to preserve every part of the wall which is still standing. Cement can only be used in total reconstruction since it would be more solid then the rest of the wall and would probably make it collapse during an earthquake. Epoxy can also be used, but is very expensive and tends not to work has well as wanted. It is mostly used to "glue" back on fallen blocks and fill in cracks. When doing any kind of restoration or reconstruction, it is important to use the same material used two thousand years ago as much as possible. Fortunately, the material is easy to find since it was mostly local stuff, even if sometimes, the colors don't match exactly.A problem restorers run into is that we are not always sure what the structure looked like two thousand years ago. So it is mostly educated guess work on their part. But when it comes to post-1980 (after the earthquake), every thing can be restored back to the original state since its appearance is well documented.In the case of painted coating, it is a little more complicated. It is now easy to restore painted coating in labs, but the in situ restorations are still very hard to do. We must start with restoring the wall itself, working from the outside of the wall which is usually in worst shape. The method that seems to give the best results is the injection of a solution that will regenerate the ancient mortar instead of replacing it. Solvents are used to clean and glue the chipping paint. The solvents are all very toxic, and, since the restorers need to work on big surfaces in closed areas, it can sometimes be dangerous for them.The humidity needs to be controlled as well. The first thing to do, is repl...
