Upper and lower tubular components of the support members are in threaded engagement for beam support. Retainer cups secure the support member in place while a lock seats about the upper and lower components to prevent rotation after installation. An opening in the upper tubular component permits charging of the support member with concrete or other reinforcing agent.

A shoring device comprises a piston and a cylinder. The piston is axially expanded by compressed gas, whereby the shoring device engages two opposing surfaces. An outer ratcheting collar and a concentrically enclosed inner ratcheting ring are mounted upon the cylinder end receiving the piston. This outer ratcheting collar mechanically and frictionally engages at least one of a plurality of serrations of the enclosed inner-ratcheting ring. The outer ratcheting collar and inner ratcheting ring firmly hold the piston, thus preventing inadvertent rotation and collapse of the piston during the shoring device application. There is also an internal circular air channel feature, which more quickly and evenly distributes compresses gas or air to the piston for lateral expansion thereof.

In a preferred embodiment, a scaffold assembly for use on a roof, including: a base for placement on a first plank disposed on a scaffold bracket attached to the roof; an outer member having a lower end attached to the base; an inner member telescopingly received in the outer member and attachable to the outer member at at least one lengthwise location; and an upper plank support attached to an upper end of the inner member for placement thereon of a second plank.

A shoring device is disclosed comprising a piston and a cylinder. The piston is axially expanded by compressed gas, whereby the shoring device engages two opposing surfaces. An outer cam collar and a concentrically enclosed inner ring are mounted upon the cylinder end into which the piston inserts. This outer cam collar comprises at least two cam edges, two stop faces and a threaded cam pin within an integral boss. The inner ring comprises a continuous circular indentation as well as a continuous circular inner lip. The outer cam collar and inner ring, together with the continuous circular inner lip and threaded pin, firmly retain the piston. These piston retention features prevent inadvertent rotation and collapse of the piston during use.

A length adjustable bar for mounting within a window opening to secure a protective panel therein includes a substantially hollow outer section having an inner section telescopingly received therein. A plurality of gear teeth are longitudinally disposed on the inner section. A cam is pivotally mounted to the outer section and includes gear teeth thereon that interengage the gear teeth on the inner section when the cam is rotated to a first position. The cam is rotated with a handle having an aperture thereon that aligns with apertures on a pair of spaced tabs when the cam is placed in the first position to receive a locking means to fix the bar at a select length. The design allows the bar to be extended to substantially the same length or width of the window opening. By pivoting the handle downwardly, the geared cam extends the inner section slightly to tightly wedge the bar within the opening.