The 32-year-old former England international was released by Reading in the summer and has since spent time with Brighton and Millwall on trial.
Having also turned out for West Brom and Aston Villa, the experienced full-back has amassed nearly 450 career appearances as well as earning two caps for England while playing in the Barclays Premier League for the Royals.
Shorey will be handed the number 22 shirt by the Robins and will be available to make his debut subject to clearance from the Football League.
- Sports & Recreation
- Barclays Premier League