One of Black's weaknesses is the pawn on d5. No other pawn can help it. The e-pawn is gone. The c-pawn has gone past c6.
A trade of pawns is likely to happen at some point, d-pawn for c-pawn. This will open up the file for the rook, and the Rook and knight will be pressuring the d-pawn. Move the e2-knight to f4 at some point and you'll have another hitting d5.
Now you might say "Well, why not ...c4 from Black?" Answer is simple. White's Light-Squared Bishop is not in position to attack d5. It will take a while. It takes only 1 move for Black to guard the d-pawn with his Bishop. Therefore, a Bishop trade for Black isn't ideal here. If Black trades Bishops, the Queen comes to d3, the pawn takes on c5 and there is a raging attack against d5.
If the Bishop takes and then ...c4 is played, the QUeen can go to f5 and if it has to retreat, it can retreat to f3, pressuring d5.
If Black plays ...c4 without trading Bishops, the White Bishop still has the f5-square, so it's not trapped, and Black's Bishop ends up even worse, being blocked by pawns that cannot move, and so White gets a kingside attack, especially on the light squares.
So Rad1 (I'm assuming that was the move here) is to set up pressure on the d-file. The fact that a Rook is on the same file as the Black Queen is an added bonus. Not singificant here, but a bonus. The significant part is the weak d5-pawn, and if ...c4, the still weak d5-pawn and bad Bishop.
I find it hard to know where to put the rooks in the opening phase. Here is an ongoing game between Aronian and Vidit where the former goes Rad1. Can anyone explain the logic of placing the rook in that crowded file?