CA1038127A - Structural element - Google Patents

Abstract

ABSTRACT

A structural element is provided which is pre-ferably made of metal or plastic and which is useful as load-bearing element for various structures, supports, bridges, vehicles, as load-bearing foundation, and for many other purposes. Such a structural element consists of two or more shells or plates which surround at least one cavity. Said cavities are equipped with load-bearing supporting elements, shells, panels, and the like which are associated with pressure plates, preferably honeycomb or grid-like plates. The ribs or ridges of said honeycombs or grids are relatively small, i.e. very narrow. The structural element, furthermore, comprises at least one flexible or movable plate which exerts a pressure onto the elements inserted into the cavity or cavities. Said pressure is equal to or greater than atmospheric pressure and higher than the pressure in the support cavity. The structural element of this invention may also be of tubular shape.
It can be provided with fire protecting or extinguishing means.

Description

10;~81Z7 1 BACKGROU~D OF THE INVENTION

2 ~l) FIELD OF THE INVE~TION

3 ¦ The present invention relates to a structural element

4 and more particularly to a load-bearing structural element useful, for instance, as wall element, for structures, 6 supports, bridges, vehic'es, and others.
7 . ~.
8 (2) DESCRIPTION OF THE PRIOR ART
9 Structural elements which consist of two or more structural shells or panels of at least one sealing packing 11 lying between the edges of the shells or panels, and a cavity 12 hermetically enclosed by thqmhave been described heretoforeO
13 1 -In the cavity of said elements pressing means, for instance, ~-14 honeycomb plates with interposed solid plates, for instance, metal plates and associated sealing plates, for instance, 16 ¦ foam-plastic plates which can be covered with vapor-proof I? sheets, for instance, aluminum foils, are provided and at ;
1~ least one of the structural shells or panels is arranged so 19 ~ that it can shift its position flexibly, or can be bent, ¦ for instance, concavely against the seal, and a vacuum is 21 produced within the cavity.
22 . As a result of the elimination of air counter-23 pressure or back pressure within the structural element, 24 the externa~ air pressure causes at least bending or sagging of the flexible structural shells or panels and/or in 26 ¦ particular a change in place of the structural shells in 27 ¦ direction towards each other by compression of the seal and I -3~

103~1Z7 1 I the cavity inserts. As a result of said atmospheric 2 1I pressure, the inserts in the cavity, particularly the honey-3 ¦! comb webs or straps, are placed under tension and press 4 I with this force against the interposed metal plates and i the inner sides of the structural shellsO This results 6 1 in increased resistance to bending of the inner plates and 7 intermediate panels or sheets supported in this manner, as 8 well as of the outer structural shells or panels, in the 9 j event that they are acted on by load in the direction of their planes. In the case of a vacuum, this amounts, 11 ¦ perpendicular to the outer shells or panels and the honey-12 ¦I comb plates on the surfaces of the metal plates arranged -13 ,! in the cavity and other intermediate plates, to about 14 11 lO tons per sq.m.
1I This atmospheric pressure is of randomly caused 16 j order of magnitude. It is determined by the gravitational 17 1 force of the earth on the atmosphere, the composition of 18 the air as a mixed gas, and the height of the atmosphere.

20 SUMM~RY OF THE INVENTION :
21 ¦ It is one object of the~present invention to provide 22 1a structural elem~nt, preferably of metal or plastic, and in 23 ¦particular a load-bearing structural element, the use of 24 which is of great advantage especially in the following fieldc :
1I Construction engineering, vault construction, dome 26 ¦¦construction, tunnel construction, underground installations, 27 1underwater structures, formation of supports, piles, girders, ~ , -.

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1 1l frameworks, masts, chimneys, also in the form of load-2 ¦¦ bearing pipes and pressure pipes, furthermore bridge 3 ¦ construction, vehicle construction, for instance of land, 4 Ij sea, air, and space vehicles, container construction, and as ~ -1 load-bearing foundation construction also for machines and 6 ¦ objects, as well as for supporting walls, water-retaining 7 ¦ dams, breakwaters, and the like, This enumeration is not 8 1 exhaustive~
9 Other objects of the present invention will become apparent as the description proceeds.
11 1 The present invention is based on the concept to 12 1' produce the compressive forces as required independently 13 j! f the above-explained compressive force caused by the 14 1l earth and thus to obtain pressure differences either with . ,.. .. I . . . - . . - - . . ...... . . . . - .... .. .. , , . ., ¦ respect to a vacuum or with respect to a partial vacuum or 16 1I some other lower degree of pressure. In this connection 17 I the extraordinary increase in the action of the pressure 18 by con~entrating a given pressure force on a few places of 19 ¦linear pressure contact is of considerable importance for 1the pressure action on solid surfaces to be supported, by 21 providing, for instance, very narrow, flexure-resistant, 22 1 low honeycomb webs of, for instance, steel, with honeycomb 23 sizes which are relatively large as compared with the webs 24 11l or bridges of the webs. In this way the result is achieved ¦I that the pressing force, instead of being transmitted from 26 1one surface to the other surface, is - corresponding to the 27 1honeycomb structure - transferred only in honeycomb-like ,' . .

¦ fashion linearly to the surface to be supported. The 2 pressing force acts only on tnese structured lines of 3 contact which are distributed in a network-like fashion 4 11 over the entire surface. If the structural shells or ~ ~¦ panels are pressed together with a vacuum in the cavity, 6 for instance, with the atmospheric pressure of about lO
7 tons, then the linear surface parts contacted directly in 8 net-like manner by the honeycomb webs, bridges or ribs 9 and constituting about 1% of the total surface of the solid-surface intermediate plate are pressed together 11 with a force of about lO0 x lO tons = lO00 tons. This 12 pressure, if necessary, can be increased as desi~ed by 13 1 alr-pressure pumps and apparatus" With a:pressure, for 14 instance, of lO0 atmospheres, there is obtained an in-1~ I crease in pressure to lO0,000 tons of pressure, with re- .
.' l 16 I spect to the direct linear net-like contact points on the 17 supporting plates which are to be pressed. The load-18 1 carrying capacity of the supporting plates pressed in 19 ¦ this manner is of about the same value insofar as the 1 intermediate spaces of the area not contacted by the 21 ~ honeycomb webs, bridges or ribs are resistant to bending 22 ¦ - under said load.
23 1 The resistance to bending of each individual 24 1 portion of the surface is caused by the resistance to I bending of the supporting plate itself with due con-26 ¦ sideration of the size of the partial surface, 27 Since, however, the individual partial surfaces ~ '"'' ' - . '~ ' ' , .

1 take up a relatively small percentage of the total 2 1 surface, their resistance to bending is correspondingly 3 ¦ high. Thus the honeycomb widths can be maintained 4 ¦ approximately large enough so that the partial surfaces S of the supporting plates which are defined by them, still 6 have the necessary resistance to bending. In this way it 7 is possible to increase the ratio of the net-like contact 8 by means of the honeycomb webs, bridges, or ribs as com-9 pared with the total area of the inner supporting plate for maximum concentration of the pressure force on the 11 smallest possible proportion of the surface of the plates 12 1 to be supported. On the other hand, the resistance to 13 bending of the supporting plates to be supported can be 14 1 increased in advance by developing them as composite . . - l -~ plates in multiple compound fashion by the use of plastic 16 ¦ material of the highest binding power, and particularly 17 ¦ by the use of solid plastic material specifically suited 18 1 therefor as center of the composite structure, by which 19 ¦ the thrust forces are prevented from loosening the outer plates of the composite plates.

21 I There can thus be obtained honeycomb widths 22 which produce a maximum multiplication of the pressing 23 ¦ forces by even further concentration on a few honeycomb 24 ¦ webs, bridges, or ribs or on pressing surfaces taken up ¦ by them.

26 ¦ Another possibility of increasing the resist-27 ¦ ance to bending resides in the development of structural 103~1Z7 1 shapes, for instance, of trapezoidal profiles or channels 2 ¦ in compound construction with solid plastic materials and 3 ¦ in the combination of such ~omno.site proiles or shapes 4 with each other. They can be covered on the outside by S flat composite plates, having a real contact with the 6 ¦ pressing means, for instance, the honeycomb plates.
7 ¦ It is advisable to support the honeycomb 8 ¦ bridges or ribs, for instance, by partially introducing 9 ¦ foam into the honeycomb in situ by means of firmly ad-1~ ¦ hering rigid foam. No evacuation of the cavities is re-11 ¦ quired. The decisive factor is the pressure difference 12 between the pressures in adjacent cavities which are 13 j separated hermetically from one another by a movable 14 ~ structural shell or plate. -- ~ .. ,,.... .......... ..... . ... . ........ ...... .. .:
15 ¦ In the same way as in the case of vacuum or 16 1 reduced pressure, it is necessary, for reasons of safety, 17 ¦ also to dïvide the cavity in which a pressure greater than 18 ¦ atmospheric is present, into a large number of small 19 1 partial spaces, for instance, by honeycombs or grids, so that they are closed off hermetically from each other and 21 ¦ from the entire cavity. In case of a partial destruction 22 1 of the outer parts of the cavity and of the corresponding 23 1 inner parts, the parts which are still not destroyed can 24 l still exert excess pressure without change. Furthermore, ¦ by the finest possible subdivision, the amount of possible 26 damage can be restricted to a minimum. Since the excess 27 ~ pressure tends to increase the volume taken up, the -. ~ . .
- ' , ' - " '; . , --1 ~038127 1 ¦ hermetic closing off of such honeycomb spaces which are 2 1 under pressure is only possible if, as the result of an 3 ¦ even greater outer pressure, the sealing plates arranged 4 ~ on the inside for sealing off of the honeycombs are

5 ~ pressed from the outside into the honeycombs by said

6 ¦ correspondingly higher pressure.

7 ¦ The movable structural shells or panels of dis-

8 placeable position must be locked in this condition of

9 their smallest distance from each other in order to de-

10 ¦ finitely maintain the compressive stress produced by the

11 I position assumed by them. For this purpose, various means

12 ~I can be provided which will be described hereinafter.

13 ! ~ ` P; t: - -~;,, '~; , ;, ., ,. . , I
- . BRIEF DESCRIPTION OF THE DRAWINGS
15 1 Various illustrative embodiments of the present 16 1 invention are shown in the drawings,without, of course, 17 ~ limiting the same thereto. Thereby reference will be had 18 ~ to producing a vacuum or partial vacuum and to producing 19 excess pressure in the structural element by introduction 20 I into an evacuation or pressure housing as well as to safe-21 ¦ ty measures for maintaining said pressure conditions.
22 In said drawings, 23 ¦ Fig. l is a vertical section through an evacua-U tor housing with composite structural-element parts arranged vertically therein.
26 Fig. 2 is a vertical section through the right-27 ~ hand portion of an evacuator housing showing the righthand 10381'~7 1 parts of part of a composite structural element provided 2 horizontally in the housing on supporting means.
3 Fib. 3 is a cross section through a pressure 4 1 housing with a composite structural element arranged ¦ therein with pressure within the cavity.
6 ~ Fig. 3a shows engagement means for connecting ~
7 1 the structural-shell surfaces which together with packings :
8 ¦ define a cavity of the composite structural element which 9 ¦ is under pressureO
10 ¦ Fig. 3b shows a bolt which is fastened on the 11 ¦ inside of one of the two facing structural shells or 12 panels and which, in the condition in which the shells or 13 paneis are at the slightest distance apart is locked in

14 ¦ said position by pressure in the pressure housing with . ,. . . . ,........ ., .... - .
I associated machines which effect screwing.

17 ¦ DESCRIPTION OF THE PREFERRED EMBODIMæ~TS
18 ¦ Fig. l shows in cross section a pressure-re-19 ¦ sistant vacuum housing l adapted to receive a composite ¦ structural element in vertical arrangement of its indivi-21 ~ dual parts and groups of partsO
22 Housing l is closed on all sides, except for a 23 ¦ front opening which serves for the introduction of the 24 ~ individual parts and groups of parts of the composite structural element. The opening can be hermetically 26 ¦ closed. Pipe 2 for establishing a vacuum or partial 27 ¦ vacuum extends through the upper housing wall la, said , - ' ' . ' ' ' '.

1 ¦ pipe having an outlet valve 3 and a branch connecting it 2 to an air pumpO Pipe branch 4 containing valve 5 serves 3 ¦ for re-introducing air.
4 Compressed-air cylinders 6 having pistons and piston rods 7 are arranged on side walls lb. The piston 6 rods are movable in airtight fashion through the walls and 7 serve to actuate reciprocatable vertical pressure plates 8 8 ¦ on slide bottom 9 of housing 1.
9 The parts and groups of parts of the composite ¦ structural element are arranged symmetrically in the 11 following manner.
12 ¦ The outer structural shells 10 are formed of composite plates consisting, for instance, of two metal 14 plates lOa having a solid plastic intermediate layer lOb, .~ . -. -- 1 - - . .. - ~ -- .
I for instance, of polyethylene (sandwich shape). The inner 16 sides of these composite plates 10 are connected with 17 boards ll of compressible material, such as plastic foam 18 boards, felt boards, rubber boards, or asbestos fiber 19 boards, for instance, by means of layers of adhesive. The free surface of these boards or plates 11 can be coated ~r~f~r~ 61y 21 ¦ with layer 12 which is 1r~er~q~impervious to vapor.
~! ~ 22 This layer can be, for instance, a metal foil, a vapor-23 impervious plastic foil, a layer of plastic applied in 24 liquid form, or the like. These parts form a compact single composite group.
26 Between said layer 12 and a following honey-27 ¦ omb plate 13 ~here ia an open air gap 14. The honeycomb ' ~
. - ' - ' , ' . ~ . . . -lU381'Z7 1 ~ plate 13 can consist of any suitable material, for in-2 ¦ stance, of metal, particularly steel or aluminum, or ;~
3 I plastic, or of cardboardO Instead of a honeycomb plate, 4 ¦ some other pressure-resistant plate having suitable per-5 ¦ forations and correspondingly remaining narrow webs can 6 ¦ be used. This honeycomb plate 13 is followed by another 7 ¦ open air gap 15. In order to assure and/or maintain a 8 ¦ narrow air gap, compressible inserts 13a can be inserted 9 ¦ in individual honeycombs, protruding slightly towards both sides. Furthermore, there is provided a composite l1 ¦ group consisting of a central load-bearing supporting 12 ~ plate 16 in the composite form metal-plastic-metal-plastic 13 ¦ metal (16a, b, c, d, and e) and on both sides of said 14 plate 16 and firmly applied thereto compressible plates or

15 1 boards 17~corresponding to those described hereinabove

16 with respect to boards llland coatings 18~corresponding

17 to those described hereinabove with respect to layer 12.

18 All the above described parts are then again provided in

19 symmetrical sequence.
Fig. 1 shows a circumferentially arranged 21 elastically compressible packing 20, for instance, of 22 - synthetic rubber, between the edge portions of the two 23 outer plates 10, The upper part of the circumferential 24 ¦ packing is provided with pipes 21 with valves 22 through 25 1 which the air which is present at atmospheric pressure in 26 ¦ the structural element can flow out into the evacuated 27 vacuum space. On the other hand, no air can pass from . ~1 v .~
: . . .

1 1 outward to inward into the structural element~ A pipe 2 ¦ or a hose connecting the structural element with an eva-3 I cuating device and extending outward through a wall of va-4 I cuum housing 1 in hermetic fashion can also be provided.
S Packing 20 can consist of several layers, particularly of 6 ¦ layers of different elasticity, for instance, formed in 7 ¦ transverse direction. The upper part of the packing can 8 ¦ be provided with horizontally extending insert strips of 9 ¦ rigid material to take up pressure, said strips being in-1~ ¦ serted, for instance, in recesses of the packingO On Il I both sides of the two outer structural plates 10, the 12 .! movable pressure plates 8 are provided as described herein _ I above. With these pressure plates, the structurai shells 14 ¦¦ or panels can be replaced in vertical arrangement with 15 I respect to each other whereby the circumferential packing 16 I and the described inserts are compressed D The air gaps 17 ! 14, 15 which previously served for evacuating the air from 18 ¦ out of the composite element are eliminated. Under the 19 I high pressure applied by pressure plates 8, the elastic inserts 13a are forced back. The plastic foam boards with 21 1 their vapor-impervious surface coatings are pressed her-22 l¦ metically into the honeycombs. In this way there is pro-23 1l duced a firm connection between the honeycombs and the 24 l plastic foam boards. When the two outer pressure plates ¦ have reached their end position, this is also at the same 26 ¦ time the predetermined end position of the outer structural 27 ¦ shells and of the inserts compressed between them. If the~

l -13-l I .
.. . . .
, ..

1 ¦ air is then let into the vacuum housing, the atmospheric 2 ¦ pressure will exert its action, The structural element ¦ can then be removed from the vacuum housing.
4 As a result of eliminating the inner pressure ¦ of the air, the structural shells are moved towards each 6 1 other and thus press the pressure-resistant honeycombs 7 ¦ against the surfaces of the bearing supporting-composite 8 ¦ plates which thus, corresponding to said pressure, are 9 ¦ held additionally in flexure-resistant fashion in vertical ¦ position. By the back-pressure of equal value acting on 11 1 the inner surface of the structural shells or panels, said¦
12 structural shells or panels are also supported on both 13 I sides in flexure-resistant manner in addition~as load-14 I bearing elements. As a result of pressing the narrow . .. .. j:..... ..... , ,,,,: ...... ,, , ,, honeycomb ribs into the elastically compressible vapor-16 impervious coated sealing plates of plastic foam, each 17 individual honeycomb is closed off in an air- and vapor-18 tight fashion. In this way the load-bearing, flexure~re-19 sistant condition of the composite element is assured.
¦ Even in the event of partial destruction of a structural 21 I shell or panel or of the edge seal, the vacuum remains in 22 ¦ all the uninjulred honeycombs and thus there also remains 23 the support for the load-bearing composite plates. The 24 packing can therefore be completely dispensed with. The honeycomb webs or ribs can in addition be connected by 26 adhesive with the compressible means which close off the 27 honeycomb openings. All composite groups and elements are , :. ' ~ :
.
' ' ' ~: - , :' ' 1038~Z7 1 combined by the atmospheric pressure into a compact ten-2 sion- und shear-resistant composite unit of increased re-3 sistance to bending.
4 Supplementing the foregoing description, it may be pointed out that the individual groups and indivi-6 dual elements within the structural element can be 7 arranged in an asymmetrical fashion, for instance, from 8 one side to the other one, depending on varying require-9 1 ments. Reasons of fire protection may also make the pro-¦ vision of other structural materials necessary.
lI ¦ Instead of providing merely one central group 12 of load-be;aring composite plates, a plura1lty of such o;r ~ :
13 I similar groups consisting of, for instance, vertically 14 l load-bearing composite elements and resilient plates ~ connected firmly to them and inserted in the honeycombs 16 can be provided following each other at small intervals 17 thus having a high load-bearing capacity.
18 The composite structural element can also be 19 made without packing 20 and such an element can then be 1 introduced into the cavity of a larger structural element.
21 ¦ The structural plates or shells of the inner structural 22 1 element can thus be connected with those of the outer 23 1 element, for instance, by adhesive plastic foils or by 24 layers of adhesive. The hollow space which then still -¦ remains free between the inner structural element and the 26 ¦ outer structural element can then be evacuated individual-27 ~ ly. Assurance of the load-bearing strength of such a ! . . .

.. .. . . . . .

1038~Z7 1 structural element is then provided by the inner structur-¦ al element.
3 Fig. 2 shows, in a vacuum housing 1, the 4 assembly of such a structural element in horizontal 5 ¦ arrangement of its parts and groups of parts. Said 6 ¦ structural element consists of two outer composite struc-7 ¦ tural plates, for instance, of two metal sheets with 8 layers of plastic arranged therebetween in composite 9 fashion and consisting, for instance, of polyethylene.
10 ¦ The inner surfaces of the shells or panels are firmly and 11 hermetically connected with honeycomb plates 13 by means 12 ,1 of an adhesive 13b, for instance, of a polyuretkane foam 13 ¦ developed for this purpose. Instead of an adhesive 14 1 plastic foam, any other connecting means can be used, for -, 1 .-. --~. - - -- . -instance, liquid, subsequently polymerizing, sealing 16 plastics. The honeycomb plates 13 are each followed by 17 an air gap 14. Thereafter, a composite group is arranged, 18 said composite group consisting of a composite sheet ¦ (sandwich type) 25a, 25b with, on both sides thereof pro-vided with compressible sealing plates 11, for instance, 21 of plastic foam, felt, asbestos, glass fibers, or rubber.
22 ¦ The surfaces~of these sealing plates bear preferably vapor-23 proof foils 12, for instance, of polyethylene or metal, 24 ¦ such as aluminum. Between these parts, at a distance established by an air gap 15, there is provided a single 26 honeycomb plate 13, for instance, of metal, plastic, or 27 ¦ cardboard. A plurality of honeycomb plates 13 can also - - . . ' ' ' . ,- - :. ~ .:
.
: . . . !
' ' ' : - .' ` , ~ ;, . ', ', . : ~

1 be combined into a sandwich with the interposition of 2 other plates, such as, sealing plates ll, for instance, 3 by means of adhesive plastic foam. The individual struc-4 tural element parts and groups of parts are held, if re-quired, at a distance apart of air gaps 14, 15 on the 6 edges of fork-shaped supporting means 26 which are ar-7 ranged movably on supporting ledges 27 of a supporting 8 frame'27~ When the air is evacuated from the vacuum 9 housing via pipe 2 with valve 3, it is then removed in the same manner from all parts of the structural element~
11 Thereupon, the movable supporting means 26 can be pulled 12 ¦ out of the air gaps 14, 15 by means of electromagnets 28 " ' ~: '' and' us'sai'd' r s-'can~ ovë ~ ly o e'' on't 'è; he 14 in the position arranged precisely, for instance, on stops 15 '' to their intended'final'position. Compressing of the , , 16 parts of the composite structural element can be effected 17 ¦ by means of pressure plate 29 which is arranged on upper 18 structural shell or panel lO, for instance, by their -19 weight, or by a compressed-air cylinder with piston and ~, piston rod 7 which moves in airtight fashion through the , 21 ¦ lid la of the vacuum housing. In this way the individual 22 honeycombs aie hermetically sealed by the adjoining foam 23 plates ll being pressed thereinto. If the air is then 24 again let into vacuum housing l through pipe 31, the parts~
will be further pressed together by the atmospheric pres-26 ¦ sure and thus all parts of the composite structrual ele-27 ¦ ment will be combined to form a compact unit.

- - ., . . .- , ~ . . - : , , - ~ - . ., ' i . ..

1038,..,27 1 Of course, it is possible also to provide a 2 packing between the edges of the shells or panels, In 3 this case the parts of the structural element can be 4 ¦ placed loosely one on top of the other up to the upper-most composite part which is borne by the packing, said 6 packing, in turn, being received or carried at the bottom 7 by supporting means with the formation of an air gapO
8 Since the air in the interior of the structural element 9 is of higher pressure than the vacuum in the housing, it flows almost completely out. For this purpose special 1l evacuating tubes or hoses can also be arranged above or 12 below the packing or therethrough preferably provided with 13 valves. The packing can also be applied subsequently and he 14 space between it and the core of the structural element 1 1~
,... I - , . -- -~ .- ;........ , ., .,...... ,. ,,, -. .-1 can additionally be evacuated. Such an element can be 16 used in various manner as insert in correspondingly larger 17 composite structural elements. It can furthermore be 18 combined in sandwich fashion with the inner surfaces of 19 larger structural shells or panels of such larger composit structural elements, for instance, by means of adhesive 21 intermediate layers, and particularly by means of adhesive 22 foils Gr adhesive solid plastic plates. Insofar as the 23 arrangement of an elastic circumferential packing between 24 the edge parts either of the larger composite structural element or of the smaller composite structural element to 26 be introduced is necessary, evacuation of the intermediate 27 space can be effected via pipes with valves between the ... .. . . .
.*w - ~ - .

1 ~ packings and the parts of the structural element.
2 ~ Provision of the air gaps 14, 15 and/or the 3 1 arrangement of supporting means 26 and electromagnets 28 4 ¦ are unnecessary in the case of the use of lighter materials , S ¦ for instance, of aluminum and cardboard honeycombing.
6 ¦ The air present in the element parts, except for a very -7 small amount, is forced to the outside during evacuation 8 1 of the vacuum housing. If a circumferential packing is 9 ¦ provided, it may then be necessary to produce a connection ¦ to the vacuum space l via a pipe with valve (see Fig. l, 11 ¦ reference numerals 21, 22). This pipe can also be 12 connected with an evacuating device by passing it through 13 the vacuum housing wall and thus will render possible 14 l evacuation of the composite structural element. Thus in ¦
.. . . ... . I , ., ,.... , . , - .... , . .: . ....... ... . -,1~ case of lightweight construction, it may be sufficient to 16 1 introduce a composite structural element - also with 17 circumferuntial packing - provided with an evacuator pipe 18 and valve mounted into a vacuum housing in order to 19 1 evacuate it by elimination of the atmospheric pressure.
¦ Thus composite structural elements of heavy individual 21 j composite elements and groups of elements can be evacuated 22 ¦ in this way vialpipes with valves, When using packings, 23 ¦ pressure plate 29 may also be dispensed with upon 24 l insertion or interspersing of pipes with valves. In all cases the means described permit complete or practically 26 complete evacuation of the air, as required.
27 The introduction of evacuated smaller structural elements achieves its importance through the possibility .

1 l of imparting to the load bearing supporting elements 2 ¦ contained in the evacuated structural element especially 3 ~ if thev are formed of composite plates in a single or 4 ¦ multiple bonded arrangement (multi-sandwich type) or in ¦ multiple group arrangement, a practically unlimited 6 ¦ increase in resistance to flexure on the structural shells 7 or panels of the inner smaller structural element due to 8 the positive pressure that can be produced in the larger 9 structural element. In this connection the outer ~ -I structural shells or panels of at least the smaller 11 j structural element can also be developed as load-bearing 12 ¦ support1ng ~1ates.. Under the posit1ve pressure which is 13 I exerted on their outer surfaces on the one hand, and the -14 i correspondingly high back pressure which is exerted on 1 their inner sides, said shells or panels are supported 16 1 with corresponding flexural resistance to receive the 17 supporting ledges or other pressures in the direction of 18 ! their plane. For this purpose the outer structural shells 19 ¦ or panels of the larger surrounding composite structural element must be able to take up, with resistance to 21 compression and bending, by suitable structural develop-22 ~ ment, the excess pressure present in the cavities. This 23 can be effected, for instance, by the provision of inter-24 1 secting profiled sheets, and particularly of trapezoidal 1 sheets, the contacting points of intersection of which are 26 ¦ welded together in multiple layer. A further increase 27 l in the bending strength of such combined shaped, and

-20-,.

1038~Z7 I ¦ particularly trapezoidal, structural shells and panels 2 ¦ can be obtained in a manner that profiling is effected on 3 ¦ composite sheets, consisting, for instance, of metal-4 ¦ plastic-metal (sandwich-shape) Or the trapezoidally 5 ¦ shaped or differently shaped sheets are first of all . :
6 I connected in this form with solid plastics of corresponding 7 ¦ shape to form profiled composite sheets (sandwich-type) .. -.
8 I which are then firmly connected with each other in a ~ -9 singly or, respectively, multiply intersecting sequence.
¦ Such profiled structural shells or panels can be developed lI ¦ by means of sheets which are closed on all sides to form 12 ¦ an airtight and liquid-tight hollow body which, for I3 1 nstance, can recelve plastlc foams-or any other substances 14 I liquids, or gases serving the purposes of the structural 1l element.
16 ¦ Fig. 3 refers to the advantages of the use of 17 I positive pr.essure in a composite structural element.
18 ¦ Fig. 3 showsdiagrammatically in cross-sectional view a 19 1 composite structural element with horizontal arrangement of the individual pàrts which are inserted in a pressure-

21 I proof pressure housing 40a, 40b, 40c.

22 ¦ . Thelcomposite structural element consists of

23 ¦ outer structural shells or panels 41 which are made from .. ..
U ~ intercombined, connected trapezoidal sheets 41a, 41b, and 25 ¦ of circumferentially extending side walls 42 and 43 .
26 ¦ arranged hermetically sealed thereon and parallel to each 27 I other, said side walls being of lesser width than the - . . :. .. . ~ . , . .- .

~ 1038~Z~
¦ distance between the structural shells or panelsO The 2 I edges of these side walls are pressed into circumferentiai 3 ¦ elastic packings 44 and 45 associated therewith. In this 4 way the hollow space between the structural shells is closed off elastically with variable air-tightness 6 and imperviousness to vapor. So as to further assure air-7 tightness, a third circumferential packing 46 can be 8 provided between the edge parts 47 and 48 of the two 9 structural shells or panels 41.
Within the hollow space, approximately in the 11 center, there is provided a pre-evacuated composite 12 structural element consisting of at least two structural I shells or panels 51,-52, preferably of compo'site sheets, ~ -14 ¦ and of one or more honeycomb plates 53, and load-supporting 15 ¦ flexure-resistant composite supporting plates 54 arranged 16 1 between the latter. This inner structural element which 1; .~17 ~ is pre-evacuated ~ on the outer surfaces of its 18 1 structural shells or panels a compressible layer 55, for 19 ¦ instance, of rubber, plastic, or plastic foam. On both sides of these surfaces 55 there are arranged honeycomb pla :es 21 ¦ 56, for instance, of steel plate, which before assembling 22 the outer structural element have been fastened hermeti-23 ¦ cally to the inner sides of its structural shells or

24 I panels 41, for instance, by means of adhesive polyurethane

25 ¦ foam 56a or liquid plastic adhesive. Thus the air can

26 possibly enter the honeycon~b plates only along the outer

27 ¦ surfaces 55 of the inner wall element.

1 ¦ Pipe 57 or the like having a valve 57a is 2 ¦ arranged towards the cavity of the composite structural 3 element. Via said pipe 57 it is possible to introduce 4 I compressed air through a compressed air device into said 1 hollow space with any required degree of pressure. The 6 ¦ outer structural shells or panels 41 are pressed by means 7 1 of said compressed air so far apart against stops (not 8 shown) that between the inner structural element and the 9 ~ adjoining honeycomb plates there is formed a fine air gap 58 by which each individual honeycomb is provided 11 ~ with compressed air to the extent contemplated. Thereupon 12 ¦ compressed air of a higher pressure than the positive 13 1 pressure in the inner structural element is introduced 14 1 into the hollow space of the pressure housing 40 by means ¦ of an air compression device via pipe 60 with valve 61.
16 ¦ Thereby the structural shells or panels 41 of the outer 17 ¦ element are pressed against each other so that the air 18 ¦ gaps 58 are closed and the webs or ribs of the steel 19 ~ honeycombs 56 are pressed into the compressible layers 55 20 or plates on the outer surfaces of the structural shells ~ -21 ¦ or panels of the inner element in an air-tight and vapor-22 ~ -tight manner. ~hus there prevails within the hollow space 23 I of the composite structural element a counter-pressure 24 ~ which corresponds to the positive pressure exerted in the ¦ hollow space of the pressure housing. In order to main-26 ¦ tain this desired pressure condition, by which the sur-27 ¦ faces of the bearing supporting means 51, 52, 55 are . ....... ...................................................... .......... ,' l l .
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l 1038127 1 ¦ propped or braced, in particular by the honeycomb plates 2 ¦ 53, 56, up to the increased bending strength corresponding - 3 ¦ to the positive pressure~ after elimination of the 4 pressure in the pressure housing 40, there are arranged along the narrow sides of the outer structural element 6 means for fixing the minimum distance between the outer 7 composite structural shells or panels 41 as it is obtained 8 by the external positive pressure. Fig. 3 shows detent g or stop means, i.e. engagement means for this purpose, on the structural shells or panels, such as protruding Il ledge-shaped parts 66 of the upper structural shell or 12 1 panel 41, and other associated parts as well as the detent ~: s~ or op ~e ~es 67 with sprlng oa ed ov 1 detè t or 14 l stop elements 68 which can be inserted into the detent or stop strips 67 and which snap behind the mating ledges 66 16 protruding on the upper structural shell or panel when 17 said structural shells or panels 41 are moved towards each 18 ¦ other. In this way the intended position of the structural 19 shells with respect to each other which is thus obtained I is fixed or locked in position and secured permanently.
21 I In this connection the lower part of the detent 22 ¦ or stop strip~is in engagement with a rectangular strip-23 ¦ shaped bend 69 of the lower outer structural shell or 24 i panel and thus prevents the detent or stop strip 67 from I changing the compressed position of the upper structural 26 ¦ shell or panel 41 secured by its detent or stop element 27 ¦ 68 by engagement after elimination of the outer positive 10a81Z7 1 1 pressure. In order to prevent lateral forcing away of 2 ¦ the detent or stop ledges 67, said ledges are pressed 3 1 movably by strong tension springs 70 in the direction 4 ¦ towards the detent or stop ledges 66. Of course, means ¦ by which it is possible, if necessary, to effect a 6 ¦ disengagement can also be provided, for instance, by 7 1 drawing back the detent or stop ledges 67 by means of 8 an electromagnet. The detent or stop means described are 9 merely one technical possibility among many others of achieving the same goal.
11 ~ Fig. 3a shows schematically in cross section, 12 supplementing Fig. 3, one possibility of connecting the two 13 I structural shells or panels 41 via the surfaces of their I ;
14 ~ inner sides, for instance, by detent or stop means in the end position imparted to them in the pressure housing, for 16 an unlimited period of time. For this purpose there are we] ded 17 onto the inner side of the lower structural shell or panel 18 41 two correspondingly large square pipes 75. Detent or 19 ¦ stop elements 76 are inserted against the action of 1 compression springs 77 between universal guides 78 in 21 said pipes. Said detent or stop elements 76 propel and 22 can be pushed in to an extent which is limited by stops.
23 ¦ They are provided with backwardly extending bevels. The 24 distance between the two detent or stop element carriers75 1 is such that said elements snap and engage into solid 26 ¦ body 79 which is welded to the inside of the opposite 27 ¦ structural shell or panel 41 and which is provided with :.. ..

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~038~Z
1 ¦ incisions 80 corresponding to the triangular shape of the 2 ¦ detent or stop elements 76 and their distances apart from 3 each other, under spring pressure 77 upon a corresponding 4 change in position, i.e. reduction of the distance bet-ween the structural shells or panels. Thus they permit further movement up to the end position only in direction 7 ¦ towards a reduction of the distance between the structural 8 shells or panels.
9 Such means which connect the inner surfaces permanently against the inner positive pressure can be lI ¦ arranged in any required number a~ suitable places of 12 ~ the surfaces 41. They can also be provided in the form 13 il of ger st s. T e lnsérts and supporting pi tes a 14 ¦¦ to be recessed at the respective places or they are to be i,¦ provided with slits or interposed slot spacings.
16 ¦ Fig. 3b shows another embodiment for connecting 17 f the composite structural surfaces 41 with each other at the 18 I minimum distance attained by the positive pressure. For 19 this purpose bolt 81 is welded onto the inner side of the ¦ cavity of the one structural shell or panel 41, said bolt 21 passing through a hermetically closed bore hole 82 in the 22 1 opposite struct~ral shell or panel 41 and being adapted 23 to be tightened by nut 83 on the outer side thereof. Said 24 l tightening must be effected in the pressure space at the 1 maximum pressure established. For this purpose screwing 26 machines 84 connected to be operated electrically from 27 ¦ the outside are arranged precisely with respect to the :. , ' ~ '. ', ' ,' ' 1 ¦ position of the nuts. In this way the structural shells 2 ¦ or panels are connected with each other at a minimum 3 ¦ distance apart attained by the positive pressure, i.e.
4 I under the condition of the highest pressing tension of ¦ the pressing means 51, 52, 53 with respect to the load-6 ¦ bearing supporting plates 54, so that after releasing the 7 ¦ positive pressure air from pressure housing 41, the con-8 ¦ dition of stress in the evacuated structural element 9 remains unchanged. , ¦ The described inner connecting means of the 11 ¦ outer structural shells or panels exert an opposing pull 12 I or countermove with respect to the compressive forces which - 13 ¦ otherwlse would cause bulging' the outer st'ructural'shells 14 ¦ or panels towards the outside and bending in of the same. ' - - ;t c.rl~ 5~0~n~ t-¦ These connecting means thus render~possible to ~ =`
16 ¦ ingly increase the bending strength of the inner bearing 17 ¦ supporting elements.
18 ¦ The invention can also be made use of in a 19 ¦ multi-shell or multi-panel composite element in such a , , ¦ manner that the outer structural shells or panels are 21 ¦ fixed in position and the inner: intermediate shells or 22 ¦ panels are arran~ed movable. Every two movable inner 23 ¦ intermediate structural shells or panels define a cavity 24 into which compressed air is introduced. In this way ¦ the distance between the two displaceable structural 26 ¦ shells or panels is increased and the pressure on the 27 cavity inserts which are placed under tension, is .. ' ~.
.. ~ ~ ' ' .

1 ¦ correspondingly increased. In order to maintain this 2 ¦ pressure, after the intended maximum distance of said two 3 movable structural shells or panels has been obtained, a 4 rapidly hardening liquid structural material can be ¦ introduced into said pressure space under an even greater 6 I pressure. In order to be able to introduce the compressed 7 ~ air which is to be displaced by this liquid structural 8 ¦ material without loss of pressure, an outlet valve can be 9 arranged in the upper air-space part, said valve making it possible that when a predetermined pressure is exceeded, 11 1 the compressed air is allowed to flow out as from said 12 ¦ predetermined degree of pressure. In this way it is also 1 ' ¦ ' possibie përmanent y to f1x the prëdëter lned optimum 14 pressure-tension condition.
¦ At the same time it is possible to span with 16 ¦ great forces ceiling and floor parts (or upper and lower r 17 ¦ parts) of s~ructural elements, for instance, for bridges 18 ¦ with such displaceable structural shells or panels and 19 1 non-displaceable outer shells or panels facing each other ¦ in a pressure cavity. For this purpose a movable 21 ¦ structural shell or panel can then be arranged against 22 following press~re means and load-bearing supporting means 23 ¦ on each of the two non-displaceable outer shells or panels 24 1 at a slight distance so as to form a pressure cavity.
~ This arrangement can be effected, for instance, for 26 bridges in recurring sequence as necessary for increased 27 tension or span of upper and lower part. ¦

I -2~

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: . . :

- : . . ' ' ., , ' ,: ~ .
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~ 10381Z7 1 ¦ It is also conceivable to provide in a pressure 2 ¦ cavity, for subdividing thereof, a plurality of air hoses 3 ¦ with individual valves to establish the intended pressure 4 ¦ in them. Upon damage to the pressure cavity, the un-¦ damaged hoses continue to exert their pressure action.
6 ¦ Extremely high compressive stresses can be exerted by 7 ¦ applying a corresponding positive pressure within such a 8 ¦ constructed structural element having non-shiftable outer 9 structural shells at least on both sides via one or more ¦ hermetically arranged structural shells or panels arranged 11 shiftable in the inside, on the load-beariny supporting 12 means associated with them, and at the same time by tautly I -13 tensioning the connecting upper cover or ceiling part and 14 lower bottom or floor parts.
The composite structural element forms a single 16 composite unit from a static standpoint. For this reason, 17 the connections between the core and the outer plates and a1 .
18 least the intermediate shells or panels must be so firm tha~:
19 the shear stresses transmitted to the boundary surfaces are taken up by the outer plates or intermediate shells 21 ¦ or panels without said plates and panels becoming loose.
22 ¦ Por this purpose the outer plates and/or shells or panels 23 are to be constructed with a sufficient minimum strength 24 ¦ as well as a sufficient minimum flexural strength.
The load-bearing supporting plates can be placed 26 ~ under compressive stress in various manners. Thus the 27 co ressive stress can be also produced by li~uids which . .
, ''', '' , '''. - ~' ~ ~ .

, ~ 1038127 1 ~ are placed under compressive stress. water of high 2 ¦ pressure can be introduced into a hollow chamber and a 3 ¦ vacuum can be present in an adjoining hollow chamber, 4 ¦ or wate~ with the normal pressure determined by the ¦ atmospheric pressure can be introduced. Such pressures 6 ¦ can be exerted also purely mechanically, for instance, by 7 ¦ lever actions against a plate o~ shell (panel) to be dis-8 1 placed, or, for instance, via/compressed air cylinder with 9 ¦ piston rods against a displaceable shell (panel).
¦ It is sufficient to effect this pressure action 11 ¦ only from one side and to have the counter-pressure which 12 ¦ is exerted via a stationary shell (panel) on the load-13 ¦ bearing support, act on the other surface of the load-14 ¦ bearing supporting means. Nevertheless it is advantageous ¦ for reasons of safety to have the pressure action exerted 16 ¦ from both sides should the pressing force fail to act 17 ¦ on one of the two shells (panels). To achieve this 1~ 1 result, it is advisable to keep as small as possible the 19 ¦ distance between the movable shell (panel) exerting the pressing force and a pressure-resistant stationary wall 21 associated with it. Should then a failure occur, the 22 required pressure will be produced by the other movable 23 displaceable shell (panel) and the full bending strength of 2~ the load-bearing supporting means will be retained by the opposite force of the stationary wall, without any re-26 duction in force. It is furthermore advisable to fill the 27 hollow space between said shells or panels with honeycomb ~ -

28 plates up to a minimum gap of less than one millimeter;

1 ¦ The use of honeycomb plates for use in the 2 ¦ pressing step differs from the use of flat plates. In the 3 ¦ case of flat plates, the pressing pressure is distributed 4 ¦ uniformly over the entire area of the pressing plate.
In the case of a honeycomb plate, however, only the very 6 narrow ribs of the honeycombs transmit the entire pressure.
7 These ribs as a rule take up less than l % of the surface 8 to be pressed. This means that the total pressure which 9 is exerted on the honeycomb plate is transmitted by these ribs with more than hundred times the force to the lines 11 of the surfaces to be pressed which are contacted by them.
12 It follows that a corresponding stress structure results fr~ m 13 said pressing lines. The free space between the ribs of 14 the honeycombs is subjected, on the other hand, to flexural forces.
16 Therefore, the honeycomb surfaces must be in a 17 specific, not to be exceeded, size ratio with respect to 18 the bending strength of the plate to be supported, on the 19 one hand, and to the load borne by the load-bearing supporting plate, on the other hand~ in order to prevent 21 bulging or bending in or kinking of the load-bearing 22 supporting plate. It is advantageous to provide for 23 optimum widths of the honeycombs with the smallest possible 24 size of the honeycomb ribs in order to increase as much as possible concentration of the energy of the respective 26 lines corresponding to the honeycomb structure. In combi-27 nation with the small height of the honeycomb ribs they 1 should also be made as resistant as possible to bending, 2 for instance, by the use of steel sheets.
3 The honeycombs in the stress cavity which 4 receives the load-bearing supports can be filled, for instance, with plastic foam for reasons of insulation as 6 well as to support the honeycomb ribs against bending in 7 or kinking. In this connection, however, said fillings 8 should not rest - or they should rest without pressure -9 against the surfaces of the supporting plates.
Instead of honeycombs, it is also possible to 11 use grids which are subdivided in the corresponding -. ,, . ~.............. .. , .~ .. , ....... , 12 optimum grid fields and which have knife-thin edges at the : - piace of contact with the load-bearing supporting platës.
14 On the other hand, it is advantageous to provide a flat shape on the presslng side. :
16 The use of the composite structural elements 17 in the building of houses requires the construction of 18 multi-shell (multi-panel) composite structural elements, 19 and at least a three-shell (three-panel) structural element. -The third shell (panel) of such an element at the same 21 time forms the inner wall of a room of the building. A
22 hollow space which in particular must satisfy the fire 23 protection requirements should be provided between said 24 third shell (panel) and the central intermediate structural shell (panel) arranged in front thereof.
26 In order to exclude collection of water of con-27 densation as a result of the penetrat~on of water vapor, . ., ,, ................... .., , ~ . . .. .
,........ - , ... ..

1 the hollow space must be closed off in vapor-tight fashion 2 on all sides. This can be done in the manner that all 3 non-metallic wall parts of the hollow space are covered, 4 for instance, with a~uminum foil or a vapor-impervious polyethylene plastic foil. However, in addition thereto 6 there is the further problem of preventing the stresses on 7 the hollow space walls resulting from variations in 8 pressure caused by temperature variations in the hollow 9 ¦ space, For this purpose the invention contemplates connecting the hollow space by a pipe with the atmosphere.
11 In this way the result is obtained that the pressure in 12 the hollow space always agrees with *he variations of pressure in the atmosphere. In order to prevent penetra-14 tion of atmospheric moisture into the hollow space, the - pipe can be hermetically provided towards the hoIlow space 16 with a flexible air bag formed, for instance, of plastic 17 foil. This air bag can be provided with spring spreading 18 means by which a necessary minimum of its fillable volume 19 is filled with outer air. If the pressure of the atmospher, , increases, then this air bag is additionally filled with 21 air, while if the pressure of the atmosphere decreases, 22 air is given off to the outside by the air bag. In this 23 way the hollow space remains closed in vapor-tight fashion 24 from the outside without it being possible for pressure variations to occur.
26 Particularly when the inner wall of the room 27 consists of a thin shell or panel of structural material, l~ilZ7 1 for instance, a plaster wall or a ceramic wall, it is 2 necessary to support said wall. This can be done by a 3 sheet metal wall which at the same time forms the structural 4 shell or panel towards the inner room. Such a sheet metal shell or panel can hermetically close off a hollow space in 6 trapezoid-like fashion, if necessary~ by two intersecting 7 trapezoidal sheets or panels and can be constructed in the 8 other direction so as to enclose the plaster wall on all 9 sides. The hollow spaces resulting from the trapezoidal profiles towards the plaster wall can also be constructed 11 in an air-tight and liquid-tight fashion and can be filled 12 with fire-retarding materials, for instance, with a ~ -13 -suitable form of asbestos. Other agents, for instance, 14 rock wool, glass, fibers, and the like can also be used for this purpose. Above these trapezoidal intermediate spaces 16 and the plaster wall there is arranged a water-bearing pipe 17 with thermostatically controlled openings directed towards 18 the rear surface of the plaster wall. If the heat of the 19 fire reaches in case of a fire the thermostats at a pre-determined temperature, for instance, through small 21 openings in the upper part of the plaster wall, then the 22 water pours out ~gainst the rear of the plaster wall and 23 at the same time enters the said cavities which are formed 24 by the trapezoidal depressions. Thereby it permeates the asbestos filling and/or the other solid fillings, for 26 instance, rock wool, which are provided therein~and wets :
27 the absorptive rear side of the plaster wall.

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ll 10381;2'7 1 .
1 The latter can be provided with bore holes 2 through which the water passes to the front side and 3 trickles down in the form of a curtain of water. In this 4 way the plaster wall will be cooled continuously and the heat of the fire will be reduced by the conversion of the 6 water into steam. The steam displaces to an extent 7 corresponding to its generation the oxygen-containing air ~ -8 and can thus increasingly exert an extinguishing action on 9 the source of the fire. A water pipe having openings directed towards the front surface of the plaster wall 11 and-controlled by thermostats can also be provided on the 12 front surface of the plaster wall. Such a water curtain 13 prevents the heat of the fire penetrating via the plaster 14 wall into the composite structural element. In this way considerable conventional fire-protection structural measur~ ~s 16 can be eliminated and saved. A further increased fire 17 protection can be effected by applying to the front plaster 18 wall a readily soluble layer of a carbonate and the water, 19 before it flows into the perforated pipes forming the water curtain, is conducted through a container in which 21 there are contained soluble agents or solutions thereof 22 which react chemically with the carbonates on the plaster 23 wall so as to liberate carbon dioxide therefrom. Providing 24 such containers of the aforementioned pipes is possible above the customarily suspended ceilings without great 26 expense. The carbon dioxide also displaces the oxygen-27 containing air and extinguishes the flames.

Il 103~127 1 The liquid-proof depressions in the trapezoidal 2 structural shells or panels can be filled with hot water 3 from a heating system for room heating or cooling. The fire .
4 protection described can be obtained in the same manner through openings towards the plaster wall 6 If a flat structural shell or panel is used, a 7 correspondingly thicker plaster wall can be provided on 8 its rear, for instance, with vertical, undulated profilings 9 to form hollow spaces. This rear side, for instance, can have pasted on a plastic foil, such as a polyethylene foil, 11 so as to achieve a water-proof and steam-proof closure. In . casë of fire, this foil melts at about ï50c. a~d, when . .. . .,- : . : - ., 13 molten, allows the water to penetrate into the absorbent .
14 plaster wall. All the other protective measures described . .
hereinabove can also be provided.
i 16 The supporting elements produced in accordance 17 with the present invention may be of any suitable shape, 18 Such supports can consist, for instance, of 19 longitudinally slit pipes which are arranged concentrically 3 20 in an unslit pipe. The pipes or, respectively, the pipe 21 intermediate spaces can be closed at their ends in an air- .. . . :.
22 tight and/or vapbr-tight manner and can be sealed elas-23 tically. Thereby the sealings are effected in such a 24 manner that changes in the diameter of the concentrically arranged slit pipes which occur when the pipes are under 26 pressure, are taken into account and the seals are not 27 endangered thereby. Furthermore, all seals can be re-. - ' . - - ~

ll 10381'~
1 inforced and secured by elastic plastic foams The inner 2 equipment of the pipes for their construction as supports 3 is in principle)aside from their round shape, the same as 4 in the case of the square composite structural element.
In order to effect compressive stresses, a change in 6 position of the slotted pipes is necessary in the same 7 way as a change in position of the structural shells or 8 panels is required in the case of the structural elements.
9 The longitudinal slits in the pipes are responsible for said change in position. Due to said slits a change in 11 the diameter of the individual slit pipes takes place under - the prëssure of intermedia'tei'y 'arranged pressure mèans,'for 13 instance, by means of compressed air or liquid under 14 pressure on the inside or the outside of the intermediate .. ~ .... .. - ....... .. . . .
load-bearing supporting pipe.
16 First of all it is necessary to seal the slits 17 elastically so as to prevent the compressed air penetrating 18 into adjacent concentric spaces. Such seals can be 19 effected, for instance, by elastic packing inserts in the slit perpendicular to the pipe surfaces. If a higher press re 21 is exerted on the slit pipe in the direction from the out-22 side, the edges df the slits will be pressed against the 23 elastic packing and thus will reinforce the seal. Pre-24 ferably, however, the entire region of the slitting of a pipe is supported and sealed with elastic sealing means 26 in addition to the two other opposite pipes.
27 ~he edges of the slits themselves can be de-10381'~7 1 formed. Thus, they can be pressed flat for sealing, for 2 instance, by rectangular bending, against the sealing ~-3 means provided between them.
4 They can also be bent by 180C, The bend can be provided with elastic sealing means and can be in 6 engagement with each other.
7 They can also engage with clamping action into 8 recesses with elastic means. Many other possibilities 9 exist.
The intermediate spaces between every two pipes -11 can, for instance, be formed as follows:
12 Air-tight sealing strips, for instance, rubber 13 strips can be bonded over the pipe slits on one or both 14 sides so as to cover the slit. Thereupon pressing means, in particular, for instance, circular honeycomb plates, -16 preferably also slit, consisting, for instance, of metal, 17 plastic, or cardboard, can be arranged in one or more 18 layers so as to fill up the intermediate space approximatel .
19 It is advantageous to use honeycomb plates having low ribs in order to achieve the best possible flexural strength of 21 the ribs. Otherwise all that has already been stated with 22 regard to the hdneycomb plates, applies to the structural 23 elements. In the case of a plurality of honeycomb plates, 24 for instance, lighter slit pipes of the same or different material can be arranged behind every honeycomb plate in 26 order to air-tightly subdivide the space and to transmit 27 pressure to the next following honeycomb plate. For static -' 1 1 reasons, it is necessary to connect all inserts firmly to 2 ¦ each other in order to be able to expose them to tension, 3 ¦ compression, and shear load.
4 ¦ - The spaces between two concentric pipes 5 ¦ correspond in their function to the hollow spaces of the ~ -6 ¦ composite structural element. As in that case, the ad-7 1 joining structural shells or panels are partly non-8 1 displaceable in position and partly displaceable. The slit pipes correspond to the displaceable structural shells 10 ¦ or panels of the structural element. Thus numerous 11 different possible combinations are available.
12 All the spaces can be provided with pipelines 13 with valves so as to apply in each case in accordance with 14 the desired combination, for instance, a vacuum to the one hermetically closed space and pressure to the two adjacent 16 spaces, In this example, the two pipes which limit the 17 vacuum space are slit and these slit pipes are pressed 18 together or, respectively, reduced in diameter b ~ he 19 compressed air in the adjacent spaces. In this manner ther~
is achieved a change in position by which increased 21 resistance to bending and thus increased load-bearing 22 capacity is impalrted thereto by pressure and counter-23 pressure from the inside. Instead of producing a vacuum 24 . in the intermediate space in this example, atmospheric pressure can, for instance, prevail therein and the excess 26 pressure in the adjacent spaces can be maintained one 27 atmosphere higher, whereby the same supporting effect is 28 obtained.

Preferably all pipes, with the exception of the outer pipe, are slit pipes which are concentrically 3 ¦ arranged one within the other with intermediate spaces.
4 In this example, compressed air can be introduced into S the cylindrical space to the innermost slit pipe. In this 6 way the diameter of this pipe is increased, whereby a 7 corresponding pressure is exerted on the pressing means, 8 for instance, on circular honeycomb plates (which are also slit) in the direction towards the outer pipe over all intermediate slit pipes and pressing plates. The outer 11 pipe, as a solid pipe, must take up the entire pressure 12 which is exerted on its inner wall and must be able to ~ :
13 respond as counter-pressure. For this purpose, pressure-14 resistant rings can be placed at suitable distances around t5 the outer pipe. In the latter case, the outer pipe can 16 appropriately be constructed as slit pipe, 17 According to another example, the excess 18 pressure can originate from the intermediate space which 19 i8 defined by the outer pipe, on the one hand, and from the cylindrical cavity of the innermost slit pipe, on the 21 other hand, so that all pipes lying concentrically there-22 between are supported in flexure-resistant fashion from 23 both sides by the pressing means.
24 By an annular reinforcement of the outermost pipe, it represents also a load-bearing supporting pipe 26 which is propped or braced with increased resistance to 27 bending from the inside, on the one hand, by the pressing _40_ ., .::~ , .
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~03812 ~
1 means acting thereon and, on the other hand, by the 2 counter-pressure originating from the rings.
3 ¦ In the same way as in the case of a structural 4 element, it is of advantage to hermetically seal at least each of the honeycombs, chambers~or the lime of the 6 pressing means in order not to impair the flexural strength 7 of the pipe supports in case one pipe is damaged. To 8 achieve this result, the procedure is the same as described 9 hereinabove with respect to the composite structural elements.
11 The grid-like pressing by means of the honeycomb 12 ribs produces the same result of concentrating the pressing 1j forces on the lines on contact. It follows that such pipe 14 supports differ only in shape from the rectangular com-,. .. , . . . .. . ,... . . ,. . ~:...... . , .. , . . .. . , . . -., , . . .. .
posite structural elements or supports. The pipes can be 16 constructed in sandwich fashion in order to increase their 17 resistance to bending. In place of circular honeycombs, 18 there can be arranged corrugated plates as pressing means 19 in the intermediate spaces. Said corrugated plates are preferably subdivided in transverse direction into a large 21 number of small compartments each of which can be 22 hermetically seaied off. The connecting means and other 23 means for maintaining an optimum supporting pressure 24 produced by temporary excess pressure can be employed in a fashion similar to that described with respect to the 26 structural elements. Furthermore, for instance, a pre-27 determined excess pressure in the cylindrical hollow space ~038127 defined by the innermost slit pipe can be maintained 2 permanently and thus without change by the introduction of 3 a hardenable liquid structural material, for instance, of concrete. The compressed air should also preferably be dehumidified by means of drying agents to such an extent that water of condensation cannot form in the hollow spaces of the pipes. . .
8 The present invention makes ~t possible to 9 take up or absorb extremely high loads by using very little material so as to support loads up to the limit of the 11 strength of the material.
12 : .

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Claims (70)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A load-bearing structural element comprising a plurality of shells surrounding at least one cavity, at least one of said cavities being equipped with load-bearing supporting elements, said load-bearing supporting elements being associated with pressure plates provided with contact ridges, said structural element having at least one movable pressing means capable of exerting pressure on said supporting elements and said plates in the cavity, the exerted pressure being at least equal to atmos-pheric pressure and higher than the pressure in said support cavity.

2. The structural element according to claim 1, in which said pressure plates consist of ribs with intermediate spaces.

3. The structural element according to claim 2, in which the individual spaces are closed in airtight and vapor-tight fashion.

4. The structural element according to claim 3 further including means for maintaining the spaces in the same cavity at pressure either above or below atmospheric.

5. The structural element according to claim 4, in which valves and pipes are associated with the cavities to produce the desired pressure conditions therein.

6. The structural element according to claim 1, in which an airtight, pressure-proof housing with a closable opening is provided around said structural element so as to produce a pres-sure above or below atmospheric in said pressure-proof housing.

7. The structural element according to claim 6, in which the pressure or vacuum is imparted to the spaces in the cavity while said housing is in the open state, and sealing means for closing the opening, said sealing means being pressed on by external pressure and sealing each individual space individually in an airtight and vapor-tight fashion.

8. The structural element according to claim 7, in which by application of a greater external excess pressure, an existing inner pressure is further increased, and means are provided for maintaining the increased compressive stress produced by the outer increased pressure in the cavity of the structural element.

9. The structural element according to claim 8, in which by the high compressive stress produced, the spaces under pressure are individually closed in an airtight manner.

10. The structural element according to claim 8, in which detent means are provided in order to maintain the increased compressive stress produced by the external increased pressure in the cavity of the structural element.

11. The structural element according to claim 8, in which liquid, hardening substances are introduced in the cavity of the structural element, the increased tension in said structural element produced by pressure being maintained permanently un-changed by said substances.

12. The structural element according to claim 1, in which said supporting elements are constructed so as to engage hermeti-cally in elastic packings by edge portions arranged vertically to their inner surfaces and placed in boxlike manner with respect to each other, thereby causing the distance between the structural shells and thus the volume of the cavity between them to be variable.

13. The structural element according to claim 6, in which an evacuated smaller supporting element is arranged as an in-ternal supporting element in a larger supporting element in compound fashion.

14. The structural element according to claim 13,in which the inner evacuated supporting element consists of at least two outer structural shells and at least one interposed load-bearing supporting element, the pressure exerted by said pressing means increasing the flexural stiffness of the structural element.

15. The structural element according to claim 14, in which said structural shells, pressure plates, and load-bearing support-ing elements are made in sandwich construction as a composite element.

16. The structural element according to claim 15, in which said structural shells, pressure plates, and load-bearing support-ing elements are of profiled shape and are connected with each other.

17. The structural element according to claim 15, in which said structural shells, pressure plates and load-bearing support-ing elements are of trapezoidal shape and are connected to each other in intersecting profiled shape.

18. The structural element according to claim 1 in which at least one position-changeable structural shell is associated with said pressing means and with said load-bearing supporting means and exerts a pressure stress on said supporting means.

19. The structural element according to claim 1, wherein at least one cavity under lower pressure is provided within said structural element, and at least one position-movable intermediate structural shell is contructed so as to transmit the higher pressure by means of pressing means provided in the cavity under lower pressure to load-bearing supporting means arranged therein for increased compressive stress, thus providing said supporting means with increased flexural strength.

20. The structural element according to claim 1, further including a pair of outer structural shells, at least one of the outer structural shells being position-movable and connected by connecting means with the other shell against a higher pressure acting on its inside.

21. The structural element according to claim 20, in which both outer structural shells are arranged fixed in position, in which at least one position-changeable intermediate structural shell dividing up the structural element in airtight manner is provided within the structural element, and in which at least one of the cavities is provided with a higher air pressure and another one with a lower air pressure or a vacuum.

22. The structural element according to claim 21, in which the cavity of the structural element is subdivided by position-changeable and fixed intermediate structural shells so that cavities of higher air pressure act via position-changeable inter-mediate shells on cavities with lower air pressure, and in which the cavity with lower air pressure has opposite the position-changeable intermediate structural shell a stationary position-unchangeable structural shell.

23. The structural element according to claim 21, in which the cavity of the structural element is subdivided by position-changeable and fixed intermediate structural shells so that cavities of higher air pressure act via position-changeable inter-mediate shells on cavities with lower air pressure, and in which the cavity with lower air pressure has opposite the position-changeable intermediate structural shell a position-changeable additional structural shell adjoining which there is a cavity with a higher air pressure.

24. The structural element according to claim 23, in which the compressive stress which is imparted by the movable inter-mediate structural shells to the stress cavity and the load-bearing supporting means arranged therein, is permanently main-tained active by means securing the position of the shells limiting the cavity even after elimination of the forces effect-ing the stresses.

25. The structural element according to claim 24, in which the pressure of the movable intermediate structural shell is exerted on the pressure plates and therefrom, concentrated by the latter, onto the linear contact points of the surfaces of the load-bearing supporting elements with a high factor of multiplication as com-pared with a surface transmission of pressure.

26. The structural element according to claim 25, in which the pressure plates are of metal and have honeycomb ribs which reflect heat rays.

27. The structural element according to claim 25, in which the load-bearing supporting means are at least partially of metal and their surfaces are bare metal in order to reflect the heat rays.

28. The structural element according to claim 25, in which the load-bearing supporting means are coated with resins which are impervious to heat rays.

29. The structural element according to claim 26, in which the ribs of the honeycomb plates are kept lower in order to ob-tain high flexural strength, in which intermediate plates are arranged between every two honeycomb plates, and in which the required total honeycomb height is produced by the number of honeycomb plates.

30. The structural element according to claim 29, in which the pressure plates are hermetically firmly connected at at least one side with the covering plate by plastic foam or hardening plastic adhesive.

31. The structural element according to claim 26, in which the honeycomb pressure plates are filled at least in part with insulating agents, the pressure from the honeycomb pressure plates onto the load-bearing supporting means being exerted only via the ribs and the ribs being supported by the insulating agents with increased resistance to flexure.

32. The structural element according to claim 1, in which the cavity is sealed at both ends thereof by means of packing members.

33. The structural element according to claim 1, in which two movable structural shells define the cavity under pressure, and in order to secure minimum spacing between such shells and prevent bulging out of the surfaces of said shells, connecting means are provided.

34. The structural element according to claim 33, in which said connecting means comprise detent means formed on one of said shells engagable in recesses formed in a member connected to the other of said shells.

35. The structural element according to claim 33, in which said connecting means are connecting bolts with nuts which are tightened by a machine provided in the pressure housing during the action of external excess pressure upon reaching the minimum distance of the structural shells from each other.

36. The structural element according to claim 33, in which the surfaces of facing structural shells are connected with each other by bolts extending transversely through the cavity and arranged on at least one of the inner sides of the structural shells.

37. The structural element according to claim 20, in which the outer shells of the structural element are arranged in a vacuum housing and rest only loosely against the pressure plates in which the air flows out under its pressure into the vacuum housing, and in which evacuation pipes and valves leading from the cavity of the structural element to the vacuum space are provided for allowing the air to flow out into the vacuum housing.

38. The structural element according to claim 37, in which in the pressure housing, pipes are conducted into the cavities of the structural element, said cavities being under pressure, in which due to the corresponding pressure in the pressure housing, the structural element is provided with excess pressure, and in which by additional excess pressure imparted to the structural shells, the predetermined increased compressive stress in the cavity is produced.

39. The structural element according to claim 38, in which in the evacuation housing the individual elements and groups of elements are arranged with the formation of air gaps, and in order to secure the air gaps spacers are provided by which the air gaps are held open until complete evacuation of the cavity inserts is achieved, whereupon the structural elements are air-tightly connected with each other by applying pressure in the vacuum housing by means of associated outer pressing plates and whereupon, by re-introduction of air into the vacuum housing, a firm connection of all parts of the structural element is achieved due to the air pressure so as to form a single compound unit.

40. The structural element according to claim 39, in which in the evacuation housing the individual structural element parts and groups are arranged horizontally over each other on load-bearing means.

41. The structural element of claim 40 further including electromagnets for removing the load-bearing parts, and in which external pressure plates are provided to effect combining of the structural element parts and groups.

42. The structural element according to claim 1. in which the structural element is arranged in assembled condition in an evacuatable, hermetically closable. pressure-resistant housing from which the air is evacuated via evacuation means, and in which the cavity of the structural element is provided with at least one outlet means, for evacuation of the air from the structural element, and means for again introducing atmospheric air into the housing, thus causing the structural shells to be pressed in the direction towards each other and propping each other and also load-bearing supporting inserts arranged on the inside.

43. The structural element according to claim 33, in which in the cavity between the structural shells a flexible air bag is hermetically arranged on an outwardly extending pipe so as to produce in the cavity a pressure corresponding at all times to the pressure of the outer air, thereby preventing dry air intro-duced into the cavity to escape therefrom, said air bag being constructed so that via spring spreading means, in case of a drop in pressure outside the cavity, air can escape against said spring action out of the air bag, the volume of the air bag, with a corresponding reduction of the volume of the air still remain-ing in the air bag and in case of an increase in pressure of the outer air being dimensioned so that it can receive the larger quantity of air necessary to produce a pressure equilibrium.

44. The structural element according to claim 15, in which the individual elements of the composite structural element are held so far apart by spacers provided in the vacuum space that the air flow completely out of them into the vacuum space, in which at least one pressure plate is provided, said pressure plate causing, after evacuation to a predetermined degree, the elements arranged above or alongside each other in the vacuum space to be combined so as to seal off each other hermetically, said pressure plate being actuated by compressed air cylinders with pistons and pistons rods, the piston rods thereof being passed from the outside air-tightly through the walls of the vacuum housing thereby closing off the air gaps between the individual elements, whereupon when outer air is subsequently introduced into the interior of the vacuum housing through a pipe and the structural shells are pressed together by said atmospheric pressure, the composite structural element forms a firm, compact, uniform, load-bearing composite body.

45. The structural element according to claim 32, in which pipes with outlet valves are provided associated with the cavities of the structural element, the structural shells jointly with the surrounding packing enclosing the inserts, whereby compression of the structural element as a result of evacuation of the air in the vacuum housing surrounding the structural element results in the enclosed air being charged substantially completely from the closed cavity of the structural element via the loosely abutting packing via the pipes with their outlet valves into the vacuum housing.

46. The structural element according to claim 45, in which evacuation or positive pressure applying devices are arranged on the inside or outside of the evacuation housing and positive pressure housing with corresponding pipes and valves.

47. The structural element according to claim 31, in which liquid means, and particularly foam-producing means, are intro-duced into the honeycomb spaces and said spaces are connected individually in airtight or vapor-tight manner with adjoining slabs, plates, and layers by mixing at least at one opening side, so as to produce an adhesive foam.

48. The structural element according to claim 47, in which the border surrounding a plaster plate is airtightly arranged on a preceeding structural shell, said border consisting of solid material.

49. The structural element according to claim 47, in which a structural shell of refractory material resistant to compression and flexure is arranged directly or indirectly behind the inner wall.

50. The structural element according to claim 49, in which a plaster wall is firmly connected with a sheet metal structural shell of trapezoidal shape and in which the cavities between said plaster wall and said sheet metal structural shell are closed in airtight and water-tight manner on all sides.

51. The structural element according to claim 50, in which trapezoidal plates are filled with plaster, concrete, or other structural material, said material being substantially in the liquid state.

52. The structural element according to claim 51, in which the trapezoidal plates are filled with plaster, concrete, or other structural material, said material being substantially in the liquid state and being re-inforced on at least one side with re-inforcing means.

53. The structural element according to claim 50, in which hot-water containers are provided, said containers having thermostatically actuated outlet valves towards the plaster wall.

54. The structural element according to claim 53, in which said hot-water containers have pipes closed by a composition softening or melting at a predetermined temperature and, in the case of fire, causing discharge of hot water into the plaster wall.

55. The structural element according to claim 53, in which profiled sheet metal shells are closed in watertight manner on all sides behind the inner-wall shell, said closed profiled shells receiving heating or cooling water and supplying the water through openings thermostatically actuated or sealed by means of agents melting at a predetermined temperature to the inner structural shell, thus preventing, in case of fire, penetration of the heat of the fire to the insulating part of the composite structural element.

56. The structural element according to claim 55, in which profilings are present on the rear of the inner-wall structural shell, said profilings receiving the water serving for protection against fire, said water flowing through pipes into the recesses of the profilings, said pipes being arranged on top of said profilings and having thermostatically actuated openings.

57. The structural element according to claim 56, in which water spraying devices are provided at least on one side of the plaster plates, and fire-extinguishing chemical substances are added to the water,

58. The structural element according to claim 55, in which bore holes are provided in the inner-wall structural shell from its rear side, said bore holes serving to receive water for pro-tection against fire, by wetting the inside of the porous inner-wall shell and allowing the water to flow out along the outer surface of the wall.

59. The structural element according to claim 58, in which agents developing fire-extinguishing gases, are provided in the fire-protection device and/or the inner wall.

60. The structural element according to claim 58, in which the rear of the inner wall is covered with a vapor-impervious plastic foil, said foil being destroyed in case of fire and rendering it possible for water to enter the inner wall for protection against fire.

61. The structural element according to claim 58, in which steam valves are arranged in the inner wall towards the inner space for removal of the steam produced from the water in the hollow space behind the inner wall.

62. The structural element according to claim 58, in which a hollow space is provided behind the inner wall or behind a structural plate supporting the inner wall, said hollow space having inserts serving for fire protection.

63. The structural element according to claim 62, in which the structural element is constructed in pipe form as load-bearing support.

64. The structural element according to claim 62, in which a plurality of slit or non-slit pipes are inserted concentrically in the tubular structural element.

65. The structural element according to claim 63, in which the pipes are closed at their ends by means of elastic packings in an airtight manner toward the outside and each other.

66. The structural element according to claim 63, in which means are provided for producing pressure or a vacuum at the intermediate spaces are hermetically closed off from each other.

67. The structural element according to claim 63, in which the pipe slits are elastically sealed.

68. The structural element according to claim 65, in which pressing means having slits or free plate ends, are arranged in the spaces between the pipes.

69. The structural element according to claim 65, in which approximately circularly curved honeycomb plates, having slits or free plate ends, are arranged in the spaces between the pipes.

70. The structural element according to claim 1, in which compressible flexible means are associated with said pressing means, said flexible means having a foil covering towards a plurality of honeycombs, said flexible means serving to hermeti-cally close each of said plurality of honeycombs.