The 21 year-old prop forward becomes the second local trialist to sign for the club ahead of the new season, following in the footsteps of hooker Kieran Cross.
Like Cross, Braham joins the club from Doncaster Toll Bar and linked up with the Dons for pre-season training back in November after being recommended by assistant coach Peter Green – a long-time stalwart at the town’s leading amateur club in recent years.
Braham previously had a spell as a youngster at Hull FC and coincidently made his Dons debut against the Black and Whites in the club’s first pre-season match during which he caught the eye of Black and Whites’ boss Lee Radford.
After an impressive first outing against the Super League side, who fielded a strong pack on the day, Braham also excelled a week ago in the club’s second warm-up match against fellow League One outfit Oxford, scoring the first try of the game as the Dons ran out 54-4 winners.
Thornton has also been pleased with Barham’s work and attitude in pre-season. The strong-running prop is expected to provide competition along with Conor Scott - to the more experienced Makali Azue and Mark Castle.
Azue and Castle have yet to feature in any of the warm-up games.