GB2147929A

GB2147929A - Building construction

Info

Publication number: GB2147929A
Application number: GB08328095A
Authority: GB
Inventors: Peter Leonard Goodhind
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-10-20
Filing date: 1983-10-20
Publication date: 1985-05-22
Also published as: GB8328095D0

Abstract

In a method for casting of an element, such as a concrete floor 12 for a building, at least part of the periphery of the element is formed by placing blocks 14, which can have a stepped external shape, around the zone to be filled, and then filling the zone with the settable material, the blocks 14 forming restraining means for the said material. <IMAGE>

Description

SPECIFICATION Building construction This invention relates to the building of houses or other permanent structures and has reference to blocks used in such construction.

It is fairly common practice to buiid houses and other structures on preformed piles which are driven into the ground and which serve as the foundations for the building. The piles are usually made of reinforced concrete. There are three common methods of building onto the tops of the piles, which are usually driven in so that their tops are approximately at soil level. In the first such system, preformed beams are placed on the tops of the piles and slabs are secured onto the beams. The beams and slabs are preformed away from the site.

The individual slabs form respective sections of the floor of the building.

In another system the beams are cast in situ onto the tops of the piles and then the slab is cast in situ onto these.

In a further system a slab, usually forming the whole floor area of the building, is cast in situ onto the piles, with which the slab may be connected by means of reinforcing bars.

The slab usually incorporates beams or reinforcing portions and this arrangement allows rather greater tolerance between the positions of the beams and of the piles since the beams tend to be wider. To cast the slab in situ requires the use of surrounding form work or shuttering which is afterwards removed.

In order that the edge of the slab is not visible on the outside of the finished building, for example where the walls are of brick, the slab edge is stepped and the formation of such a step is relatively expensive in form work and in the time required to prepare it.

Although the invention is primarily concerned with the latter form of construction, where an in situ slab is to be cast, the invention is also applicable to other circumstances in which a slab or other concrete or other settable material element is to be cast, and in which the edge or part of the periphery must have a more or less complex shape.

It is the object of the invention to provide a means whereby the casting of elements from a concrete or similar settable material and having complex peripheral or part peripheral shape is facilitated.

In accordance with the present invention there is provided a means for facilitating the casting of elements of a settable material comprises providing one or more preformed blocks of the same or substantially the same material as that from which the element is to be cast, said block or block forming, in the finished element, at least a part of the periphery of the element, said block serving as a restraint for the material in its flowable form during casting, the block or each block having a complex external peripheral form.

In the preferred arrangement the settable material is concrete and one or more of the blocks, also of concrete but being preformed, are positioned to provide form work or shuttering for the material in its flowable form.

According to a further aspect of the invention there is provided a method of casting an element of a settable material and in which at least part of the periphery of the element has a complex form, the method comprising placing one or more blocks with complex external peripheral form, and formed from the same or substantially the same material as that with which the element is to be formed, the blocks being placed to form at least part of the periphery of the volume which the element is to occupy, then filling the remainder of the volume with settable material in its flowable form, the block or blocks serving at least in part as restraint for the said material.

In the context of this invention reference to complex form is to be taken to refer to simple or complicated shapes which would be costly and/or difficult to cast as part of the periphery of the whole element.

The blocks become a part of the structure of the finished element and are fully capable of accepting loads of performing other structural function of the complete element.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a cross-sectional view of a preformed block constructed in accordance with the invention, and Figure 2 is a cross-sectional view of part of a building incorporating the block shown in Fig. 1.

The building construction shown in Fig. 2 represents part of the edge of a house, or other similar building. This is of the kind built upon concrete piles, one of which is indicated at 10. The piles are driven into the ground so that their upper ends are approximately level with the ground though reinforcing bars indicated at 11 are left projecting upwardly.

These may be of any convenient shape such as the outwardly turned form illustrated.

The piles are formed using standard techniques usually of concrete and are located as appropriate to support the loadings of the completed building and serve as the foundations of the building.

A concrete slab or raft 1 2 is cast in situ onto the tops of the piles 10 as shown. This incorporates the reinforcing bars 1 3 which may be connected with the upstanding reinforcing bars 11 of the respective piles. In order that the slab 1 2 may be cast in situ, it is necessary to surround the volume which will be taken up by the slab by formwork but in place of the conventional wood formwork usually used for this purpose, there are placed around the periphery of the zone to be filled to form the slab 1 2 a number of blocks indicated at 14 in Fig. 2 and shown on a larger scale in Fig. 1.

The block 14 shown in Fig. 1 is of gener ally L-shap thus defining a step 1 5 providing a hqrizontal upwardly presented surface. The block is pre-cast from concrete and incorpor ates reinforcing bars 1 6 which, in this example, run in several directions and are interconnected in conventional way. Ends of the reinforcing bars to extend out of the upright long face of the L. This face may be rough-cast as indicated at 1 7. The dimensions of the block are variable in accordance with differing requirements but, typically, may be 300 mm in height and 200 mm wide. The step may be 1 50 mm in height and width. A block length may be between 600 mm and 800 mm for laying by hand and up 3 metres for laying by mechanical means.

Referring again to Fig. 2, the blocks 14 are placed end-to-end around the periphery of the space in which the slab 1 2 is to be cast and this form a complete enclosure into which concrete in liquid form can be poured. Any necessary alignment work and levelling of the blocks is carried out before pouring and in this way levelling of the finished floor surface is greatly facilitated and speeded up.

Since the concrete blocks are of the same material as that from which the slab is cast, the resultant complete slab has the L-shape on its external periphery on all sides. Specially shaped or shorter blocks may be used to produce the required shape of the slab but, in this example, the step 1 5 is provided all the way around the completed slab without interruption.

As shown in Fig. 2, brickwork 1 8 may be built onto the step 1 5 and thus at its lower edge beneath the floor represented by the top surface of the slab 1 2. The inner skin of a cavity wall, represented by bricks or other building blocks 19, may rest on the upper level, represented by the top of the block and the adjacent portion of the slab 1 2.

If soil level is brought up to the bottom edge of the brickwork 18 no concrete edge is visible in the completed building and this produces an acceptable external appearance for the building.

In the process of casting the slab 1 2 the reinforcing bars 1 6 of each of the blocks are incorportated and embedded in the slab 1 2 and thus a firm key is produced between the slab 12 and the surrounding blocks 14.

The blocks may serve a secondary function, for example having holes performed in them to accept posts or other items and this is more easily carried out in the factory conditions in which the blocks are made, than would be the case on site.

It will be apparent that blocks 14 of the type shown may be used in the casting of slabs of any shape that may be required.

Furthermore, blocks with other external shapes may be used as formwork for the casting of slabs or other elements of any desired form or purpose. Furthermore, the principle can be used with materials other than concrete. The principle, however, involves the use of easily placed blocks which perform a permanent structural function and which have shapes which are difficult or in convenient to produce by conventional formwork. The blocks may be used for a part only of the periphery of a slab or other cast in situ element. The process greatly speeds up build ing operations since it eliminates the use of conventional form work requiring construction and assembly and its subsequent dismantling.

Claims

1. Means for facilitating the casting of elements of a settable material comprising providing one or more preformed blocks, said block or blocks forming, in the finished element, at least a part of the periphery of the element, said block serving as a restraint for the material in its flowable form during cast ing, the block or each block having a complex external peripheral form.

2. Means as claimed in claim 1 in which the settable material is concrete and one or more of the blocks, also of concrete but being preformed, are positioned to provide form work or shuttering for the material in its flowable form.

3. A method of casting an element of a settable material and in which at least part of the periphery of the element has a complex form, the method comprising placing one or more blocks with complex external peripheral form, the blocks being placed to form at least part of the periphery of the volume which the element is to occupy, then filling the remainder of the volume with settable material in its flowable form, the block or blocks serving at least in part as restraint for the said material.

4. A method as claimed in claim 3 in which the element to be cast is a slab formed form settable material, the method comprising placing columns in position below the zone in which the slab is to be cast, placing blocks around the periphery, each block having a surface forming a boundary portion of said zone, and then filling the zone with the settable material.

5. A method as claimed in claim 3 or claim 4 in which the blocks are preformed of the same settable material used to fill said volume.

6. Means for facilitating the casting of elements of settable material substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

7. A method of casting an element of a settable material substantially as hereinbefore described with reference to and as shown in the accompanying drawings.