A pipe clamp assembly includes a band having an inner annular seal element wrappable around a pipe, opposing clamp members extending from the band, and tightening elements for clamping together the clamp members. The tightening elements are positioned at or near opposite ends of each of the clamp members. A stiffening element is constructed of an elongate beam with mounting holes near opposite ends of the beam. The tightening elements pass through the mounting holes of the stiffening element. There are no tightening elements along a length of the stiffening element between the mounting holes.