A deformable device includes a deformable beam or hinge having an extended state, a flattened state, and a rolled state if a beam, where a stiffness and strength of the deformable beam or the hinge in the extended state is greater than a different stiffness and strength of the deformable beam or the hinge in the flattened state. A cross section includes a first about V shape half and a second about V shape half. Each half includes a vertex with at least one curve extending into two walls at least one of the walls including a plurality of truss members, both of the walls extend into a joining edge. The first about V shape half and the second about V shape half are joined together at a seam of a joining edge of the first about V shape half and the second about V shape half.

In a roofing structure, two roof panels with different slopes and lengths are positioned back-to-back, the vertical back walls of the panels having a uniform height. The seam between the two differently-sloped panels are connected by a ridge cap set at a uniform height. The ridge cap covers the seam, extending on both sides to a distance from the back walls of the roof panels sufficient to create a capillary break therefrom (preventing moisture migration) and then downwards and slightly towards the back walls of the roof panels, thereby using gravity to direct the water into the downward sloping roof panels.

A mast assembly (10), a method of deploying a mast (20), a slit locking clamp (50) for a mast and to a support assembly (14) for an extendible member (20) are provided. The mast assembly (10) comprises an extendible mast (20) configurable between a coiled form and an extended form. When extended the mast is resiliently biased in the form of an elongate tube having a slit along its length defined by longitudinal edges of the mast. When coiled the mast is opened out at the slit to a flattened cross section and wound about an axis extending transversely to the longitudinal extent of the mast. A slit locking clamp (50) clamps across the slit in the mast at a position along the length of the mast so as to stabilise one edge relative to the other.

A deformable device includes a deformable beam or hinge having an extended state, a flattened state, and a rolled state if a beam, where a stiffness and strength in the extended state is greater than a different stiffness and strength in the flattened state, the deformable beam or the hinge deformable along a long axis. An end face cross section transverse to the long axis includes a first periodic curved member which defines at least two shaped curves. A second periodic curved member defines at least two shaped curves. The second periodic curved member is mechanically coupled to the first periodic curved member at respective ends of the end face cross section. The first arc length of the first periodic curved member and the second arc length of the second periodic curved member are of about a same arc length.

An extendible membrane system may include: an extendible central column; one or more membranes; and/or one or more foldable membrane supports configured to support the one or more membranes. Each of the one or more foldable membrane supports may be configured to extend from the extendible central column. In some embodiments, one or more of the one or more foldable membrane supports includes two or more segments that may be configured to couple with each other. A method of deploying one or more membranes may include unfolding one or more foldable membrane supports from a folded configuration to a linear configuration. An extendible membrane device may include one or more membranes and one or more foldable membrane supports configured to support the one or more membranes.

A foldable quad-chord truss which can be connected end-to-end with like trusses. The chords of each pair of chords are rigidly attached, and connector members intermediate the ends are each swivelly attached to each of the chords of each chord pair to effect the folding into a compact shape for transport and storage. The connector members are adapted for attachment to beams or connector members thereof which beams may extend between a parallel pair of the trusses.

A hybrid structure includes a frame member with at least three walls, forming a channel having a convex portion where two walls meet. A concave deformation is present in at least one convex portion, wherein the concave deformation extends into the channel and has open ends forming an opening through the convex portion. A plastic reinforcement member is present in the channel, wherein a portion of the reinforcement member extends into the opening and on the concave deformation.

A composed element includes at least two panel-shaped elements, which each have an edge zone in which coupling means are present in a profiled part respectively extending in the longitudinal direction of the respective edge zone, and each including an end face extending transversely to the respective edge zone. The profiled parts allow the coupling of the panel-shaped elements together in an interlocking manner. At least one of the panel-shaped elements includes an arrangement which hides from view at least a portion of the profiled part formed at the pertaining edge zone at the location of the end face.

A method of forming a post sleeve within a post hole in the ground to include a post receiving cavity to insertably receive and support a post is provided. The method includes positioning a post sleeve core within the post hole with the aid of an elongate installation member and depositing uncured material into the post hole to at least partially surround the post sleeve core while the post sleeve core is attached to the elongate installation member. The method further includes allowing the uncured material to harden around the post sleeve core to form at least a portion of the post-receiving cavity of the post sleeve and removing the post sleeve core from the hardened material to expose the post receiving cavity to receive and support the post. Other related methods of forming post sleeves are also provided.

A method of forming a post sleeve within a post hole in the ground to include a post receiving cavity to insertably receive and support a post is provided. The method includes positioning a post sleeve core within the post hole with the aid of an elongate installation member and depositing uncured material into the post hole to at least partially surround the post sleeve core while the post sleeve core is attached to the elongate installation member. The method further includes allowing the uncured material to harden around the post sleeve core to form at least a portion of the post-receiving cavity of the post sleeve and removing the post sleeve core from the hardened material to expose the post receiving cavity to receive and support the post. Other related methods of forming post sleeves are also provided.