Abstract: A lightweight concrete mixture (e.g., comprising cement and polystyrene foam) is introduced into a compactable mold having a mold cavity defined by plural wall structures including at least two compacting wall structures. After introducing the lightweight concrete mixture into the compactable mold, the compacting wall structures are moved such that the lightweight concrete mixture is compacted in the mold cavity. The respective positions of the plural compacting wall structures can be maintained during curing of the lightweight concrete mixture such that the lightweight concrete mixture is held under compression during curing. A compactable mold may also include one or more tubes for forming tube-shaped cavities within a building block formed in the mold. Tubes can form intersecting cavities within the building block. Tubes can remain stationary while the compacting walls are moved, even when the tubes are attached to a compacting wall.

Abstract: A compactable mold comprises a main mold frame structure and plural wall structures including two end wall structures and two side wall structures. The plural wall structures define a mold cavity for forming a block from a mixture introduced into the mold cavity. At least two of the plural wall structures are movable wall structures for compacting the mixture. A described compactable mold has end walls and side walls that are shaped for forming tongue and groove features on a compacted block, and the end walls and side walls are movable such that a formed block can be released easily from the mold. A described compactable mold comprises at least one tube attached to at least one of the compacting wall structures. The compacting wall structures are operable to compact the mixture by moving toward the center of the mold cavity while the at least one tube remains stationary.

Abstract: A lightweight concrete mixture (e.g., comprising cement and polystyrene foam) is introduced into a compactable mold having a mold cavity defined by plural wall structures including at least two compacting wall structures. After introducing the lightweight concrete mixture into the compactable mold, the compacting wall structures are moved such that the lightweight concrete mixture is compacted in the mold cavity. The respective positions of the plural compacting wall structures can be maintained during curing of the lightweight concrete mixture such that the lightweight concrete mixture is held under compression during curing. A compactable mold may also include one or more tubes for forming tube-shaped cavities within a building block formed in the mold. Tubes can form intersecting cavities within the building block. Tubes can remain stationary while the compacting walls are moved, even when the tubes are attached to a compacting wall.

Abstract: A compactable mold comprises a main mold frame structure and plural wall structures including two end wall structures and two side wall structures. The plural wall structures define a mold cavity for forming a block from a mixture introduced into the mold cavity. At least two of the plural wall structures are movable wall structures for compacting the mixture. A described compactable mold has end walls and side walls that are shaped for forming tongue and groove features on a compacted block, and the end walls and side walls are movable such that a formed block can be released easily from the mold. A described compactable mold comprises at least one tube attached to at least one of the compacting wall structures. The compacting wall structures are operable to compact the mixture by moving toward the center of the mold cavity while the at least one tube remains stationary.