This is a nice article that propose several nondestructive techniques to evaluate the masonry wall capacity prior to design any repair technique

http://www.structuremag.org/article.aspx?articleID=1620

Before any test, you can look over this database

in order to have a range of aspected values.

http://www.reluis.it/dbuninadist/

I suggest to have a look to the deliverables of the 5th FP EU Project ONSITEFORMASONRY ( http://www.onsiteformasonry.bam.de/website.htm ) that investigated diagnostic methodology based on Non-Destructive Testing (NDT) and Minor-Destructive Testing (MDT) techniques.

Even this catalogue can be helpful: https://niker.dicea.unipd.it/ . This online database was developed in the framework of the 7th FP EU Project Niker (New integrated knowledge based approaches to the protection of cultural heritage from earthquake induced risk - http://www.niker.eu/ ): it links earthquake-induced failure mechanisms, construction typologies and materials, interventions and assessment techniques.

http://www.onsiteformasonry.bam.de/EXT_results.html

https://niker.dicea.unipd.it/