Most forcefield are disabled by pulling out a plug, if that helps. if you're where I think you are, there may be another route through a little hole in the side wall.
You need to open the containment fields for the turrets, which are on the right side of control room, then use then to kill soldier guys, then the slut will do the force fields via computer.
Hit the button on the cabinet, grab the turrets with the gravity gun and place them back-to-back and the door you came through (facing to the sides, of course). Be wary of manhacks and one soldier who shoots down from the balcony (look at the window to see him).