Concrete masonry hollow block

This invention relates to a concrete masonry unit such as a building block, a construction with concrete masonry units, and a method of construction using these concrete masonry units.

It is known to use concrete hollow blocks for building. These are traditionally made from a very dry no-slump concrete being a cement and aggregate mixture. This mixture is compressed and/or vibrated while in a mould to an extent to be self-supporting, and then subsequently quickly removed from the mould and handled for curing and other treatment away from the mould.

Such traditional blocks also are traditionally used in construction by using a wet mortar bed on which each block is supported. Each block is adjusted in position by a skilled tradesman to be appropriately aligned, then the mortar is left to cure. Such cure can take such time that it may limit the number of blocks that can be located one above the other in a single session.

Costs associated with the construction then are driven by a need for skilled tradesman to prepare each mortar bed, apply end mortar where the block none the less is very heavy in most cases, and then adjust a final location for alignment of the block with other of the blocks already positioned.

A further challenge with traditional masonry concrete blocks is their appearance.

An object of this invention is to reduce at least to some extent one or more of the above difficulties.

Other objects and advantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.

In one form of this invention there is proposed a building block having a body with three sets of opposing outer sides defining thereby a generally rectangular outer shape, the body having at least one passageway having an upper open end at a top of the block and an open lower end at a bottom of the block, an inner part of the block being of a first material and a second different material from said first material surrounding the inner part providing thereby an at least substantially continuous outer surface of said second material, and a one side of a one of the sets of opposing sides having at least one protrusion extending outwardly from a planar surface of the side, and at least one cavity in the further opposed side of the same set of opposed sides in a position and of a size to receive and effect an alignment of a further block having the same shape and size of this first defined block, by receiving a or the protrusions into the cavity or cavities.

Preferably, the second material is denser than the first material.

Preferably, the second material is a cementitious material.

Preferably, the second material is made from a mix comprising at least in the main, cement, sand and water.

Preferably, the first material is a mixture of expanded plastic particles and a cementitious binder.

Preferably, the first material is a mixture including at least in the main, cement, sand, water and expanded polystyrene beads.

Preferably, the first material includes an additive to ensure that the expanded polystyrene particles or beads are compatible with the wet mixture, and be mixable therewith.

Preferably, the additive is added to the water prior to the dry components being added to the same.

Preferably, the outwardly extending protrusion extends from an upper face of the block, and the cavity is formed in the bottom or underneath face of the block, and wherein in use, the cavity is adapted to accept an outwardly extending protrusion of a further block for the purpose of joining and causing to be aligned the two building blocks.

Preferably, one or more slots divide the outwardly extending protrusion, so that a further block can register and nest therewith in either an overlapping or fully coincident registering position.

Preferably, the protrusions are substantially rounded.

Preferably, in the alternative, the protrusions are of a substantially rectilinear shape

Preferably, the protrusions are orthogonally symmetrical with respect to the block,