WO1995000724A1

WO1995000724A1 - A method for casting an insulated wall and a disposable formwork to be used for and an insulated body to be used when carrying out the method

Info

Publication number: WO1995000724A1
Application number: PCT/NO1994/000112
Authority: WO
Inventors: Nils Nessa; Dag Pettersen
Original assignee: Nils Nessa; Dag Pettersen
Priority date: 1993-06-23
Filing date: 1994-06-20
Publication date: 1995-01-05
Also published as: NO932300D0; AU7086194A; NO177803B; NO932300L; NO177803C

Abstract

One has aimed at providing a rational method for casting a wholly (in full length) or partly (in longitudinal sections) insulated wall or other building component in, preferably reinforced, concrete. Thus, a disposable formwork is used, comprising a number of interconnectable, substantially tubular formwork elements (1a - 1f), each defining an internal partial cavity (e.g. 1f'). When formwork elements are interconnected, said partial cavity communicates with adjacent partial cavities through apertures formed in the formwork elements (1a -1f). The apertures enable flow of concrete between the formwork elements, and may be used for the passage of reinforcing rods (7, 7a). For the object defined introductorily, insulation (6, 6a) is inserted into at least some of the cavities (e.g. 1f') defined by the interconnected formwork elements (1a - 1f), in which cavities said insulation is positionally fixed shape-determinedly because of complementary desing and/or force-determinedly by means of spacer means, e.g. in the form of reinforcing rods (7, 7a) placed at least one free side of said insulation (6, 6a).

Description

A method for casting an insulated wall and a disposable formwork to be used for and an insulated body to be used when carrying out the method.

The present invention relates to a method for casting a wholly (in full length) or partially (in longitudinal sections) insulated wall or other building component in preferably reinforced concrete by means of a disposable^' formwork comprising a plurality of interconnectable, substantially tubular formwork elements, each defining an internal partial cavity, said partial cavities in interconected formwork elements being in communication δwith adjacent partial cavities through apertures provided in the formwork elements, enabling concrete flow between the formwork elements, said apertures possibly being utilized for the passage of reinforcing rods.

Interconnectable disposable formwork elements of the kind concerned are primarily known from Norwegian patent specification No. 165,605. However, these are not formed with a view of enabling casting of a wall or the like which is insulated over the entire length or in longitudinal sections, respectively. Insulating such a wall, requires the erection of an internal framework (half-timbering) which is filled with insulation and thereafter faced/boarded. This involves time-consuming and laborous additional operations.

In accordance with the present invention, one has now provided a method which is substantially simplified in relation to prior art technique. A method of the kind defined introductorily distinguishes itself according to the invention primarily in that insulation is inserted in at least some of the partial cavities defined by interrconnected formwork elements, and there is positionally fixed shape-and/or power-determinedly by means of spacer means placed at at least one free side surface of said insulation.

As an insulation element is fixed positionally within said partial cavity, the positional fixing is substantially simplified in connection with e.g. walls to be insulated over longitudinal sections only, as compared with a formwork having smooth internal side walls, wherein insulation bodies which only are to extend over sections of a casted, insulated wall's length, would have to be secured within the formwork in a completely different way (possibly nailed down) .

According to the invention, reinforcing rods are suitably used as spacer means for insulation, said reinforcing rods having a length corresponding to the extent of several interconnected disposable formwork elements in the longitudinal direction of the wall formwork.

When a central insulation-accommodating "chamber" is to be defined within each partial cavity to be insulated, it is then appropriate to place two parallel extending reinforcing rods, preferably symmetrically positioned with regard to the longitudinal centre plane of the formwork.

In accordance with the invention, in reinforced walls or other building components, wherein reinforcing rods are inserted into the disposable formwork, a spacer means, such as an iron rod, may be placed next to such a reinforcing rod, resting against the latter, said iron rod not having to contribute to the reinforcing function, for defining an insulation-accommodating chamber within a partial cavity.

With the method according to the invention, any suitable and appropriate kind of insulation may be used, even if, for the time being, rigid, preformed insulation bodies or elements are preferred, preferably comple entarily shaped to the internal wall surface portions of the formwork elements, against which each single insulation body comes to rest, more or less loosely. If a force fit can be achieved between formwork element and insulation body, such a shape- determined positional fixing alone may be sufficient in order to keep the insulation body properly in place. Such a shape-determined positional fixing may be complemented or entirely substituted, respectively, by a power-determined connection, wherein e.g. spacing means, such as reinforcing rods, exert a positionally fixing pressure against an insulation body.

In longitudinal wall sections, where neither insulation nor double reinforcement are needed, it may be suitable to use disposable formwork elements which, in addition to their ordinary coupling means for interconnection with other, identically shaped formwork elements, are formed with at least one extra set of coupling means for the connection of narrower formwork elements extending along said longitudinal wall section.

In order to facilitate the flow of concrete around reinforcing rods bordering on insulation, rigid insulation bodies may advantageously be used, said bodies according to the invention being provided with projections from at least one side face, so that said reinforcing rod is prevented from resting directly on the adjacent side face of the insulation body. Said projections which may have the form of small knobs, beads or the like, are thus acting as spacing means between insulation body and reinforcing rod(s).

The insulation is inserted into the longitudinal mid-layer of the formwork, defined between two horizontally extending reinforcing rods or the like. Alternatively, the insulation may be placed along one of the side faces of the formwork, or along both side faces. In principle, there is nothing to prevent placing one insulation body in the middle and another insulation body at one or both side walls of the formwork.

According to the method as set forth in the invention, one may cast insulated, load-bearing wall structure.:; and insulated, non-load-bearing wall structures. For resulting load-bearing walls, insulation will be inserted into the disposable formwork centrally or at one or both sides, while in resulting non-load-bearing walls substantially more insulation may be inserted into the formwork, e.g. both centrally within the formwork and outwardly toward the side walls thereof. In cases where one does not have a need for a formwork element having insulation or double reinforcement, one may connect to one or more narrower formwork elements which thereby extend over a longitudinal section of the resulting wall.

In an insulatable disposable formwork which may be used in order to carry out the method, it is possible to fill some of said reinforced partial cavities completely or substantially completely with concrete which, upon hardening, form "columns" of a wall structure, while the remaining partial cavities are insulated and filled with concrete only outermost at the side walls of the formwork.

Further features, advantages and technical effects in method, formwork and insulation according to the invention appear from the following description of examples of possible embodiments illustrating the invention.

Reference is made to the accompanying drawings, wherein:

Figure 1 shows a perspective view of three disposable formwork elements coupled together in per se known manner in order to form a longitudinal section of a wall formwork;

Figure 2 shows a corresponding perspective view, wherein instead of one of the identical formwork elements of equal width is connected to a substantially narrower formwork element which, together with several connected equal formwork elements (not shown) are to extend over a longitudinal section of a wall formwork where double reinforcement or insulation is not needed;

Figure 3 shows a horizontal section of a longitudinal section of a wall formwork comprising totally six identical formwork elements, where the internal partial cavities of the formwork have varying degree of filling in respect of insulation and concrete, two partial cavities in the middle having less insulation filling and more concrete filling than the remaining partial cavities;

Figure 4 - 9 show three interconnected, mutually identical formwork elements seen in horizontal section/top plan view,

Figure 4 showing a centrally inserted insulation, defined between two parallel reinforcing rods extending in the longitudinal direction of the formwork, the insulation being in the form of rigid insulation bodies, and where reinforcing rods/iron rods inserted inwardly of said parallel reinforcing rods, serve as spacers for the insulation bodies;

Figure 5 showing insulation bodies inserted within two opposing areas of two partial cavities, and wherein as in figure 4 two horizontally extending, parallel reinforcing rods have been disposed, said rods restricting the freedom of movement of the insulation bodies inwardly from the outer positions thereof. Instead of using vertical reinforcing rods as in figure 4, the insulation bodies are formed with small projections at a face which will be directed inwardly, said projections functioning as spacers as well as securing that concrete gets the opportunity of flowing outwardly past the reinforcing rods, covering these completely;

Figure 6 showing an embodiment wherein the insulation only consists of insulation bodies inserted outermost at one side wall of the formwork;

Figure 7 showing an embodiment where the insulation covers approximately one half of two adjacent partial cavities, i.e. that the insulation extends from an imaginary longitudinal mid-plane of the formwork to one side face thereof;

Figure 8 showing an embodiment where the insulation covers more than half of two coherent partial cavities;

Figure 9 showing a case where two partial cavities/formwork elements included in a wall formwork, not shown, do not contain insulation; they are wholly filled with concrete, apart from two horizontally extending, parallel reinforcing rods which, possibly, may be omitted.

In order to explain the disposable formwork elements and the formwork, reference is made to figures 1 and 2.

In figure 1, three identical interconnectable disposable formwork elements la, lb and lc are coupled together by means of coupling means of the engaging type. These coupling means may e.g. be formed such as shown and described in NO patent No. 165,605.

As a rule, these coupling means will have the form of cooperating tongues and grooves exhibiting L- respectively U-shaped cross-section. At one end, the coupling means consist of L-shaped tongues 2 and, at the other end, of U-shaped grooves 3.

In order to enable connection of one or more formwork elements 4a of a narrower design, figure 2, where neither double reinforcement nor insulation are needed, extra L- shaped coupling means 2 ' may be disposed at one end of the ordinary formwork elements la - lc. The narrow element's 4a coupling means are denoted 2" and 3'.

Each formwork element la - lc and 4a defines an internal partial cavity la' - lc' and 4a¹, respectively, which - when two or more formwork elements are interconnected - communicate with each other through apertures 5 formed in the walls of the formwork elements, thus constituting a portion of a coherent formwork cavity, such that concrete may flow between the partial cavities la¹ - lc' and 4a¹.

In figure 3, six formwork elements la - if are interconnected to form a longitudinal section of a wall formwork. It is assumed that a load-bearing wall is needed within the area of the formwork elements lc and Id, while the wall sections represented by the formwork elements la, lb, le do not need to be load-bearing.

Therefore, within the partial cavities of the formwork elements lc, Id, peripheric insulation bodies 6 have been inserted. At one side thereof, these insulation bodies are shaped complementarily to the adjacent portion of the polygonal formwork elements la - If according to the embodiment. The element If is shown in an empty condition, in order to illustrate the shape of the partial cavity If.

A horizontal reinforcing rod 7 serves, together with the shape-determined connection between insulation body 6 and formwork element, to fix the respective insulation body 6 positionally.

In order to prevent that the reinforcing rod 7 comes to rest direct]y against the opposing side face of the insulation body 6, thereby blocking the flow of concrete around the reinforcing rod 7 , each insulation body 6 is formed with small projections 6' which, thus, serve as spacers.

Within the remaining partial cavities of the formwork elements la, lb and le, rigid insulation bodies 6a are inserted, the latter being shaped complementarily to the cross-sectional portion of the partial cavity to be covered by each insulation body 6a (more than 50% in the embodiment shown) , said insulation bodies, moreover, being fixed positionally by means of a common horizontal reinforcing rod 7a. The insulation bodies 6a have also small projections 6 ', which may have the same shape as the projections 6', and which act in the same manner as these.

Figure 4 shows an embodiment where central insulation bodies 6b having rectangular cross-sectional shape have been inserted into two of three coherent partial cavities of interconnected formwork elements la - lc. These centrally placed insulation bodies 6b are, prior to the concrete casting process, positionally fixed by means of two parallel, horizontal reinforcing rods 7b and vertical reinforcing rods 8 or similar spacer rods which may, but do not have to, be incorporated into the regular reinforcement. The vertical reinforcing rods 8 serve approximately the same purpose as the projections 6', 6a' of the insulation bodies, namely to ensure flow of concrete also at the inner side of the horizontal reincorcing rods 7b.

As for the embodiment according to the preceding figures, the interconnected formwork elements la - lc of figure 5 have octagular cross-sectional shape, and rigid insulation bodies 6 are allotted a circumferential shape which complementarily corresponds to the inner wall portion of respective formwork element la, lb against which they come to rest, whereby a certain shape-determined positional fixing of the insulation bodies 6 is achieved, said positional fixing being assisted by two horizontal, parallel reinforcing rods 7b, which causes a power- or force-determined positional fixing in respect of the insulation bodies 6. As for the embodiment according to figure 3, the insulation bodies 6 have projections 6' acting as spacing means, ensuring flow of concrete also outside the reinforcing rods 7b. The mid-space between the insulation bodies is filled with concrete.

The embodiment according to figure 6 differs from that of figure 5 only in that insulation bodies 6 of figure 6 merely are placed at one side of the formwork. A wall casted in accordance with the suggestion of figure 6 would, of course, have a larger load-bearing strength then walls casted in accordance with the suggestions of figure 4 and 5, because the concrete cross-section is the largest in figure 6. In figure 6, only one horizontally placed, longitudinal reinforcing rod 7b serves as positional fixing means for the insulation bodies 6, while a reinforcing rod 7c, parallel with the reinforcing rod 7b, exclusively is included in the wall reinforcement.

The embodiment of figure 7 differs from that of figure 6 merely in that concrete and insulation in figure 7 each covers approximately one half of the cross-section of the partial cavities la' and lb'. A central, horizontally extending reinforcing rod 7b forms a positional fixing means for insulation bodies 6c, while a reinforcing rod 7c, parallel to the reinforcing rod 7b, merely is included in the wall reinforcement. Again, 6' denotes projections on the side face of the insulation bodies 6c which is directed towards the positional fixing reinforcing rod 7b.

In accordance with figure 8, within a disposable formwork, insulation bodies 6a are inserted prior to the concrete casting process, said insulation bodies covering the central and one outer portion of the partial cavities, only the other outer portion being capable of receiving concrete. Positional fixing of the insulation bodies and spacing in respect of the reinforcing rod 7b are effected in the same way as in figures 5 through 7.

Figure 9 shows a longitudinal portion of a wall formwork, where interconnected formwork elements la and lb do not contain insulation. In such a wall, the completely concrete- filled formwork elements la, lb - possibly more than two interconnected elements - form a load-bearing "column", while other formwork elements, not shown, of the same wall formwork will be provided with insulation of desired shape and desired positioning and positional fixing within the individual partial cavities la' - If.

Claims

C l a i m s

1. A method for casting a wholly (in full length) or partly (in longitudinal sections) insulated wall or other building component in, preferably reinforced, concrete, using a disposable formwork comprising a number of interconnectable, substantially tubular formwork elements (la - If) , each defining an internal partial cavity (la¹ - If¹) , said partial cavities - when formwork elements (la - if) are interconnected - communicating with adjacent partial cavities (la' - If) through apertures (5) formed in the formwork elements and enabling the flow of concrete between the formwork elements, said apertures (5) possibly may be used for the passage of reinforcing rods (7, 7a - 7c) , c h a r a c t e r i z e d i n that insulation (6, 6a - 6c) are inserted into at least some of the partial cavities (la' - If) of interconnected formwork elements (la - If) , and there are positionally fixed shape- and/or force- determinedly by means of spacer means (7; 7a; 7b; 8), said spacer means being placed at at least one free side of said insulation (6, 6a - 6c).

2. A method as set forth in claim 1, c h a r a c t e r i z e d i n that as spacer means (7; 7a; 7b; 8) reinforcing rods or similar rods are used, said rods being brough to extend through a plurality of interconnected formwork elements (la - If) .

3. A method as set forth in claim 2, c a r a c t e r i z e d i n that into the disposable formwork two parallel and substantially horizontally extending reinforcing rods (7, 7a; 7b) are inserted, and that said rods are brought to define a centrally positioned insulation-accommodating space in each of those partial cavities (la' - If) through which said reinforcing rods (7, 7a; 7b) extend.

4. A method as set forth in claim 1, wherein into the disposable formwork reinforcing rods (7b) are inserted, said rods are to be included into the regular reinforcement of the resulting wall or other building component, c h a r a c t e r i z e d i n that an e.g. vertically extending iron rod (8) or similar rod-shaped member is placed resting against such a reinforcing rod (7b) , said iron rod (8) or the like, thus, serving as a spacing means for the subsequently inserted insulation (6b; figure 4) .

5. A disposable formwork to be used for carrying out the method as set forth in the preceding claims, wherein the wall or similar to be casted, over certain longitudinal sections does not need double reinforcement or insulation, and wherein the interconnectable formwork elements (la - lc; figures 1 and 2) have mutually cooperating coupling means (2, 3) of the engaging type, e.g. in the form of tongues (2) meshing with grooves (3), c h a r a c t e r i z e d i n that at least some of the formwork elements (la - lc) have extra coupling means (2¹), possibly complementing the ordinary coupling means (2) , enabling connection of narrower formwork element(s) (4a) extending along at least one longitudinal section.

6. An insulation body to be used when carrying out the method as set forth in claims 1 - 4, wherein rigid insulation bodies are used, c h a r a c t e r i z e d i n that a portion of the circu ferensial surface of respective insulation body (6; 6a; 6c) is shaped complementarily to that inner surface portion of respective formwork element that defines that portion of the partial cavity that will be covered by respective insulation body (6; 6a; 6c).

7. An insulation body as set forth in claim 6, c h a r a c t e r i z e d i n that at least that side surface of respective insulation body (6; 6a; 6c) that will be free upon its insertion into the disposable formwork, is provided with projections (6'; 6a*), serving as spacing means in respect of adjacent reinforcing rods (7; 7a; 7b), in order to enable flow of concrete around the latter.