A rotor blade assembly for a turbomachine, the rotor blade assembly comprising: a first rotor blade and a second rotor blade positioned circumferentially adjacent to one another, the first rotor blade and the second rotor blade each comprising: a platform; and an airfoil extending radially outward from a root coupled to the platform to a tip, the airfoil including a pressure side surface, a suction side surface, and a part-span shroud (72, 73) extending from the airfoil and disposed between the root and the tip, the part-span shroud (72, 73) having a pressure side portion extending from the pressure side surface and a suction side portion extending from the suction side surface, wherein the suction side portion of the part-span shroud (72, 73) of the first rotor blade and the pressure side portion of the part-span shroud (72, 73) of the second rotor blade form an interface joint with one another; and first and second pin dampers (402, 404) each positioned within and extending between both the part span shroud (72, 73) of the first rotor blade and the part span shroud (72, 73) of the second rotor blade at the interface joint, wherein the first and second pin dampers (402, 404) are movable relative to the part span shroud (72, 73) of both the first rotor blade and the second rotor blade. a first rotor blade and a second rotor blade positioned circumferentially adjacent to one another, the first rotor blade and the second rotor blade each comprising: a platform; and an airfoil extending radially outward from a root coupled to the platform to a tip, the airfoil including a pressure side surface, a suction side surface, and a part-span shroud (72, 73) extending from the airfoil and disposed between the root and the tip, the part-span shroud (72, 73) having a pressure side portion extending from the pressure side surface and a suction side portion extending from the suction side surface, wherein the suction side portion of the part-span shroud (72, 73) of the first rotor blade and the pressure side portion of the part-span shroud (72, 73) of the second rotor blade form an interface joint with one another; and a platform; and an airfoil extending radially outward from a root coupled to the platform to a tip, the airfoil including a pressure side surface, a suction side surface, and a part-span shroud (72, 73) extending from the airfoil and disposed between the root and the tip, the part-span shroud (72, 73) having a pressure side portion extending from the pressure side surface and a suction side portion extending from the suction side surface, wherein the suction side portion of the part-span shroud (72, 73) of the first rotor blade and the pressure side portion of the part-span shroud (72, 73) of the second rotor blade form an interface joint with one another; and first and second pin dampers (402, 404) each positioned within and extending between both the part span shroud (72, 73) of the first rotor blade and the part span shroud (72, 73) of the second rotor blade at the interface joint, wherein the first and second pin dampers (402, 404) are movable relative to the part span shroud (72, 73) of both the first rotor blade and the second rotor blade.