Abstract: A sand spike system anchors a cable in an earthen substrate. A penetrator connected to the cable has folded petal-shaped sections of spring steel propelled into the earth by a propellant. Cables connected to opposite petal-shaped sections help arrest penetration and spread the folded petal-shaped sections outwardly to increase the resistance to tensile loads. Sand spike system may use a delay activated or an electrically initiated propellant to drive the penetrator into the earth instead of mechanical, hydraulic, or pneumatic force. This permits remote initiation of sand spikes from a safe distance on land or underwater. In addition, each sand spike creates far a greater surface area to entrain and use the earthen substrate and not friction to anchor, and, as a consequence, it safely bears greater tensile loads on the cable.

Abstract: A supportive walker includes a front frame, a rear frame with a connection bar connected thereto and a pair of retaining frames connected to the front frame so that the connection bar extends through the two passages of the two retaining frames. A safety device has an engaging portion and an urging device which is biased between the retaining frame and the engaging portion. The engaging portion is releasably engaged with the connection bar by operating the urging device. Therefore, the front frame and the rear frame are expanded or folded securely when the urging device is released. The connection bar of the rear frame is movable in the passages of the retaining frames when the urging device is pressed.

Abstract: A thermoplastic building block consisting of a hollow block molded out of a thermoplastic resin such as an aromatic polycarbonate resin. The block has molded flanges extending outwardly from the outer surfaces of the block. The flanges have interlocking means such as ribs on the under side of the extended flanges so as to join the corresponding outer flange of an adjacent block. The joining means do not require the need for cementing or adhesive bonding the flanges together. The block may be used to form a straight or curved wall.

Abstract: A structure for positioning on a roof to retard snow or ice accumulation thereon is provided. The structure generally comprises an elongate fin arrangement including a central vane. The central vane comprises a material which will absorb solar energy and radiate heat, to inhibit snow buildup around the structure. The elongate fin arrangement optionally comprises an upper vane structure, and a lower cover. A combination comprising a structure as described, and a roof surface, is presented. Methods of assembly and use are also provided.

Abstract: A safety device in the form of a building component (3) which has a channel (1) along which a traveller (4) may move. The traveller (4) has attachment means (5) for attachment to a safety harness. The building component (3) can be in the form of a roof ridge section (6) and can have an internal or external channel along which a suitable traveller (3) can move. The building component (3) can also be in the form of a gutter section (7), roof tile (9) or other component.