A permeable surface covering unit comprises a top surface, a bottom surface and at least two pairs of sides. A cavity is formed in the unit from the top surface to the bottom surface, and has side walls. The cavity may be a side cavity between units and/or a core cavity within the unit. An undercut is provided in the cavity. Pervious material plugs fill the cavity and extend into the undercut. Thereby the plug is locked into the cavity like a rivet and resists being dislodged by mechanical or hydraulic forces.

A mould for a skimmer box lid includes a mould body having a floor and a sidewall extending from the floor. The sidewall defines a side of a mould cavity in which a settable material can be received. A slot member projects from the floor and into the mould cavity. The slot member defines a passage with a transverse cross-section that is elongate and has a width of less than 10 mm.

A mould for a skimmer box lid includes a mould body having a floor and a sidewall extending from the floor. The sidewall defines a side of a mould cavity in which a settable material can be received. A slot member projects from the floor and into the mould cavity. The slot member defines a passage with a transverse cross-section that is elongate and has a width of less than 10 mm.

A high temperature fastener including a bolt and a nut, where the bolt and the nut are constructed of an aluminum oxide ceramic material reinforced with silicon-carbide crystal whiskers or silicon nitride.

A machine for and method of manufacturing concrete U-wall type construction blocks by molding each concrete u-wall construction block from concrete poured about a block cage made from reinforcing material while said block cage is loaded within the machine. The method involves providing a system of molding jacket panels, including a core molding assembly having a pair of inside stem jacket panels that are adjustably supportable in a substantially parallel manner during a molding process, and arranged is such a manner that the front wall portion is molded in downwardly facing direction toward a horizontal support surface and completely enclosed in one or more molding jacket panels. Before block molding operations, the thickness of the front wall portion of the U-wall construction block is set by determining the thickness of a front wall surface liner and installing the front wall surface forming liner within the system of molding jacket panels.

A method of manufacturing a nerve regeneration device for treating a spinal cord injury comprises providing a mould comprising a bottom plate, a top plate and a centre part, each having a number of holes corresponding to points in the injured spinal cord where nerves should be regenerated, and the centre part having a channel therethrough, placing first flexible elongate structures in the channels, each structure exiting the mould through one hole in the top plate and a matching hole in the bottom plate, filling the mould with a biocompatible or biodegradable material to produce the device, and removing the device from the mould when ready.

A method of manufacturing a nerve regeneration device for treating a spinal cord injury comprises providing a mould comprising a bottom plate, a top plate and a centre part, each having a number of holes corresponding to points in the injured spinal cord where nerves should be regenerated, and the centre part having a channel therethrough, placing first flexible elongate structures in the channels, each structure exiting the mould through one hole in the top plate and a matching hole in the bottom plate, filling the mould with a biocompatible or biodegradable material to produce the device, and removing the device from the mould when ready.

A base assembly with a pair of doors slidingly attached to the base assembly for moving between an open position and a closed position. An inner core comprising a first end and a throat end with the throat end having a larger diameter than the first end is positioned downward on top of the base assembly with the first end in an upright position. A pallet is positioned around the throat end of the inner core. When the pair of doors are in the closed position, a cavity is formed that is open from the top of the pair of doors and is located between the inner core and the pair of doors and corresponds to the shape of the concrete product with the flared end. The foregoing assembly allows for wet casting concrete products in a vertically upright position.

A base assembly with a pair of doors slidingly attached to the base assembly for moving between an open position and a closed position. An inner core comprising a first end and a throat end with the throat end having a larger diameter than the first end is positioned downward on top of the base assembly with the first end in an upright position. A pallet is positioned around the throat end of the inner core. When the pair of doors are in the closed position, a cavity is formed that is open from the top of the pair of doors and is located between the inner core and the pair of doors and corresponds to the shape of the concrete product with the flared end. The foregoing assembly allows for wet casting concrete products in a vertically upright position.

A process for forming an artificial reef includes forming a form having a geometric shape, applying at least one blockout onto a surface of the form such that the blockout extends outwardly of the surface of the form, applying a sprayable concrete over the form and over a portion of the blockout, curing the sprayable concrete on the form for a period of time such that the sprayable concrete adheres to the blockout, and removing the cured sprayable concrete and the blockout from the surface of the form. The blockout is of a cast concrete material such as a cinder block. The blockout has openings therein so as to open to an interior of the artificial reef.