EP0092526B1

EP0092526B1 - Method and means for concrete cavity building

Info

Publication number: EP0092526B1
Application number: EP83830044A
Authority: EP
Inventors: Roberto Buoro
Original assignee: ARBLOC Srl
Current assignee: ARBLOC Srl
Priority date: 1982-04-15
Filing date: 1983-02-28
Publication date: 1986-06-11
Also published as: IT1158092B; IT8283360A0; EP0092526A1; DE3364004D1; ATE20372T1

Abstract

A method for concrete horizontal superimposed row burial niches building, comprising an expanded plastic extractable block form core (1, 2) with hooking means (8), covered with a flexible covering plastic bag (12) which after the concrete grouting is hardened, remains glued in the concrete layer allowing the easy extraction of the extractable block form core (1, 2) and a new covering bag (12) can be replaced for covering the block form core in order to allow the re-utilization of the form core in another concrete grouting, and so on for further concrete groutings.

Description

The present invention relates to a method and means for constructing an array of concrete open-fronted cavities.
More particularly, the method and means are directed to the construction of burial niches for burying, in which a plurality of burial niches or tombs, divided by concrete walls and placed in several superimposed storeys are provided, with the characteristic that each burial niche has a frontal opening for the access.
The methods known in prior art are the following:

1. the oldest system consists in casting a first concrete layer with a set of vertical reinforcing steel rods for the post walls, providing the forms for the vertical walls, setting up these forms only to the height of the inside of the burial niches, casting the concrete into the forms to realize the partition walls, dismantling the forms after hardening of the concrete, and re-shuttering of the following covering slab, grouting and so on;
2. a more recent method consists in utilizing metallic forms with metallic cores for the concrete grouting to build said burial niches;
3. an even more recent solution provides the utilization of wood cores shaped as pre-fabricated hollow open boxes in the place of the metallic cores which however remain fixed in the concrete layer and are wasted.

The first method involves a large amount of shuttering material and manual labour, with high execution costs and a long time for construction;

the second method is much more efficient than the first one but it involves the utilization of an expensive equipment, it requires transport and handling of very heavy metallic caissons and the utilization of likewise heavy metallic cores, which after every concrete layer must be accurately scraped off, cleaned and then reoiled with detaching material layer;
the third method, more rapid than the preceding ones, obviously is of considerable cost for the loss of the used cores which remain fixed in the concrete layer of the burial niches.

A further method provides extractable form cores of different parts in order to reduce their dimensions to extract the dismantled parts from the interior of the realized cavity, see for example DE-A-2104878 (Hartschaum-Kunststoff), this solution is facilitated by utilizing three rigid plastics foam pieces coated by polyethylene film, but the extraction is actuated transversally and the first step concerns the extraction of the intermediate composable core piece. The solution is complex and cannot allow the axial extraction for realizing crypts which are too long for the system.
A further method provides collapsible core forms, see for example: US-A-3801060 (FRATESSE) and FR-A-2230834 (L. KESTING et al.) utilizing both complicated and expensive mechanical solutions, and FR-A-1423536 (BAV-ANT) utilizing an expensive collapsible form core realized by rubber material inflated by fluid.
A further method provides a combination of these last two solutions, see for example DE-A-2025954 (J. DEUERER), being a very complicated and expensive mechanical solution.
A further method provides a duct passing across the extractable form core within the interspace between the interior form core surface and the opposed formed surface, compressed air being injected through this duct in order to facilitate the extraction of said form core, see for example FR-A-1539088 (MATERIEL SPECIAL D'ENTREPRISES). This solution facilitates really the extraction of the form core but requires very expensive and complicated air compressed system.
The object of the present invention is to provide a remedy to said disadvantages. The method according to the invention is defined in claim 1. An extractable form core for use in this method is defined in claim 2.
The advantages offered by the invention are mainly that extremely light cores are utilized, losing, during their extraction, only the covering bags, thus saving:
with reference to the first solution, the expensive forms; with reference to the second solution, the handling of heavy form cores, their cleaning and treating with detaching materials; with reference to the third solution, the losing of only the very cheap flexible covering bags.
With reference to the further other prior art solutions the crypts may be realized more easily with reduced costs, since the form core of the invention is very simple and inexpensive compared to collapsible (US-A-3801060, FR-A-2230834, FR-A-1423536) or decomposable (DE-A-2104878) form cores or combinations thereof (DE-A-2025954) or to other systems utilizing extraction compressed air apparatus (FR-A-1539088).
According to tests, the best cores in expanded material are those realized in expanded polystyrene which can be used several times, and, according to the experiments, more than ten times, which will involve a very low cost in burial niches construction (crypts).
Further preferred features of the invention are specified in the dependent claims.
Some ways of carrying out the invention are described in detail below with reference to the annexed drawings which illustrate some preferred embodiments, in which:-
Figure 1 shows a first form of the core in a perspective view; Figure 2 is a back view of the core shown in Figure 1; Figure 3 is a sectional transversal longitudinal view on the vertical plane of the core shown in Figure 1; Figure 4 is a section on the median transversal horizontal plane of a modified form core with a transversally placed iron reinforcement for the extraction, in order to allow the core extraction in a transversal direction instead of longitudinal direction as the preceding ones; Figure 5 is a first step frontal view of reinforced concrete burial niches set realized with a longitudinal extraction form core system of the type shown in Figures 1, 2, 3; Figure 6 is a plan view of the first disposition of the form cores for grouting the concrete according to Figure 5; Figure 7 is an upright sectional view on the vertical longitudinal plane of the concrete grouting of a first row of burial niches as shown in the preceding Figures 5, 6.
More particularly, Figures 1, 2, 3 show a form core for longitudinal horizontal extraction, which is constituted by gluing two parallelepipedal expanded polystyrene blocks 1, 2, slightly rounded at the corners 3 and presenting a longitudinal groove 4 in such a way that when joined (glued) on an opposed joining face 5, a parallelepiped block as shown in Figure 1, with a slight tapering "a" for the extraction on the four lateral longitudinal surfaces can be realized with grooved back surface 6 for the purposes which will be explained further on. The two half blocks 1, 2, before being glued together on the opposed joining faces 5, receive a metallic tie rod 7 supporting a front projecting ring 8 and a back plate 9 constituted by two half plates 9', 9"jointed by a longitudinal central opposed welded bent edges joint 10, and said plate 9 is glued on the grooved back surface 6 of the two blocks 1, 2, and presents holes 11 which communicate with the free space of the longitudinal groove 4 in such a way that air can freely pass from the front surface of the block form core to the back surface to avoid vacuum formation and make the extraction easier.
As can be noticed from Figures 5, 6, 7, after the concrete foundation slab 14 with vertical reinforcement nets 15 has been grouted, the form cores "A" are placed equidistantly spaced and parallel to one another by means of supporting and spacing vertical posts 16 in order to realize around the cores "A" an interspace perimetrically contained by the caisson-form "C" cooperating with upper spacers "d". For further grouting of the concrete walls in a progressive step a board is placed over the cores "A" (not shown) in order to avoid their displacement (in an alternative embodiment, on the form core upper face 13), under the cover bag 12, a steel plate is placed, glued on the upper half-block surface 1). The grouting can be made first to realize the back concrete wall "Sp" and after the lateral walls "S1" completing the grouting to realize the entire thickness of the covering slab defined by the spacers "d" and height of the back or lateral vertical panels "C".
When the upper grout surface 17 has been levelled, and after a slight hardening of the concrete a new row of form cores "A" can be applied on to prosecute the building process in similar manner.
When the concrete is hardened, the extraction of the entire form core blocks 1, 2 can be carried out for each burial niche (crypt), while the plastic covering 12 remains fixed in the hardened concrete.

Claims

1. A method of constructing an array of concrete open-fronted cavities by utilizing false- works (C) and extractable cores (1, 2), each core being constituted by an expanded plastics block having the intended shape of the cavity and a venting duct (4) extending between the front and rear faces, said block being provided with a covering in the form of an open flexible plastics bag (12), the bag having the same shape as the core and being adapted to allow easy extraction of the core therefrom, comprising the steps of arranging said covered cores on a concrete base (14) within a false-work form (C), the cores being spaced apart by means of frontal spacers (d) which serve also to define the forward extent of the cast concrete, pouring concrete into the spaces defined by the cores, false-work form and spacers up to a level (17) above the upper surface of the cores thereby producing a layer of said cavities surmounted by a concrete slab, repeating the procedure on this concrete slab, allowing the concrete to harden and extracting the plastics blocks by means of hooking means (8) on the front faces of the blocks while allowing the plastics bags to remain in the cavities, air being allowed to enter behind the core during extraction by means of said venting duct (4).

2. An extractable form core (1, 2) for use in the method according to Claim 1 comprising a plastics block (1, 2) covered with an open flexible plastics bag (12) and having hooking means (8) on its front face for extracting said block, characterised in that said block is formed of expanded polystyrene, said hooking means is attached to a tie rod (7) extending through the block and connected to a form core back plate (9), and a venting duct (4) is provided in said block extending between the front and rear faces of the core.

3. A form core as claimed in claim 2 characterised in that said back plate (9) is metallic and is glued to the rear face of the block.

4. A form core as explained in claim 2 or claim 3 characterised in that said form core is composed of two longitudinally divided semiblocks (1, 2) glued together, said venting duct(s) (4) is (are) realized by grooves in the respective gluing surfaces of said semiblocks (1, 2) and the tie rod(s) (7) connecting said hooking means with the back metallic plate (9), is (are) placed between said form core semiblocks.

5. A form core according to the claim 4 characterised in that said tie rods (7) are fan disposed in said gluing plane.

6. A form core according to any preceding claim characterised in that said venting duct (4) between the front and the back surface of the extractable block form core (1, 2) surrounds the tie rods (7) of the hooking extraction means (8) and the back plate (9) has suitable holes (11) to connect said duet (4) with the back surface of the extractable block form core (1, 2).

7. A form core as claimed in any of the preceding claims characterised in that the back plate (9) is provided with inside ribs (10) which fit in the expanded plastics extractable block (1, 2)..