If you are looking for positional patterns, read Nimzo's "My System". Many modern books also cover this subject.
However, if you are looking for positional ideas, read Capablanca's "Chess Career" and use his "Chess Fundamentals" and "Last Lectures" as a supplement to better understand some of his notes.
My System by Nimzowitsch
Chess Puzzle Book 4: Mastering the Positional Principles by Muller
Techniques of Positional Play by Bronznik
Pawn Power by Kmoch
Grandmaster Positional Play by Jacob Aagaard
Grandmaster Strategic Play by Jacob Aagaard
Art of Positional Play by Reshevsky
My rating is around 1500. I have already read Silman's "How to Reassess Your Chess" and have found it very instructive.