EE and crew were turning a floor brace using a sleever bar in one of the bolt holes. Brace was on flat side. EE standing on E side of the N/S aligned brace pulling on the bar toward EE. In the line of fire when piece reached tipping point where crew needed it for rigging to put in place. Piece reached tipping point, EE lost footing. The sleever bar struck EE's leg causing cut.