EP0599283B1 - Vertically perforated lightweight brick - Google Patents

Abstract

The invention proposes a vertically perforated lightweight brick having a perforation pattern made up of perforations which form a plurality of perforation rows, extending in the longitudinal direction, and are separated from one another by webs (6). In order to achieve an improved coefficient of thermal conductivity and to reduce the longitudinal conduction of sound, the combination of the following features is proposed: thickness of the webs (6) </= 5 mm; ratio of the largest and smallest internal width of the perforation cross-section is between 1:1 and 1:2.5; spacing (a) of the perforation rows </= 22 mm; proportion of perforations >/= 50%; and relative density of body >/= 1.5 kg/dm<3>. Hexagonal perforations with the corners directed towards the side walls (5) and a fibrous pore-forming agent are preferable. The abutment surfaces should be configured in an essentially mirror-symmetrical manner with respect to one another, with the result that the protrusions (8) rest against one another and the depressions (9) each form a cavity (10) together. <IMAGE>

Description

The invention relates to a perforated light brick according to the Preamble of claims 1 and 3. Such bricks become Execution of brick masonry mainly in residential construction used, conventionally bricked or as a facing brick walled up with thin-bed mortar. The holes form above and below open continuous vertical channels.

Bricks of this type are known from GB-A-434 127, which in Years 1934. Back then, perforated brick was new by extruding the clay. They are lace patterns with square, triangular, hexagonal and others Hole shapes specified, the spacing of the rows of holes 14.5 up to 19.5 mm and the respective webs everywhere have the same thickness. However, these well-known bricks can in the sense of today's technical language not as a light brick be called, because a porosity of the clay was then not yet known. In this respect it is not for the expert surprising if the mentioned in the script Production trials already have a web thickness as small as 4.7 mm could be achieved.

On the other hand, they are mostly used today known brick a so-called slot perforation, including a emphasizes oblong hole cross section of rectangular, elliptical or similar shape is understood. The The longitudinal axis of the hole cross section extends in Brick longitudinal direction and the holes of adjacent rows of holes often offset in the longitudinal direction. The best in terms of thermal insulation, especially in Bricks known in Germany have a coefficient of thermal conductivity of λ = 0.16 [W / m · K] or worse.

The effort to make the slit-shaped holes to complicate the Making heat transfer longer and longer, however, finds its Limit in an increased brittleness of the brick, because such Long-wall bricks are neither pressure-resistant nor cross-tensile. The Compressive strength and the transverse tensile strength are so far insurmountable barriers on the way to bricks with yet better thermal insulation. And finally there is to note that in known thermally optimized Slotted perforated bricks are the acoustic phenomenon of so-called longitudinal sound conduction occurs.

The invention has for its object a lightweight brick to propose one with sufficient static strength significantly better thermal insulation behavior than known ones Light brick has, in particular, a coefficient of thermal conductivity λ ≤ 0.15 [W / m · K] and at the same time has a good airborne sound absorption capacity (Sound rigidity) with no tendency to Sound line has.

This task is the beginning of a hole with light brick mentioned genus solved according to the invention by the features of claims 1 and 3.

The basic idea is that one Hole arrangement with many small holes and short bars too with porous brick material high rigidity and measured in terms of the proportion of holes can achieve high compressive strength. Essential determinant of thermal properties is the web thickness. It is therefore advisable to proceed as follows: that first the web thickness to the smallest possible value is determined and then patterns with increasing percentages Percentage of holes depending on their static and acoustic suitability are investigating.

Already with a web thickness of 4 mm with moderate porosity can be very low with a hole percentage of 50% or more Thermal conductivity figures can be achieved.

Hole cross sections are in the form of regular hexagons particularly suitable. This is given in the honeycomb Structure can be used in the new dimensioning for bricks extreme use of thin bars. The compressive strength of a brick with filigree hexagon honeycomb perforation is the same Brick bulk density at least 25% higher than that of known ones Bricks with the usual hole patterns.

The ideal thing about the honeycomb perforation is also remarkable Mouthpiece barrel. One reason for this is that the web thickness are the same at every point. But also compared to one similar to filigree check patterns, the clay runs essentially better through the mouthpiece because the bridges do not cross, but only three bridges meet. In an intersection the clay shoots ahead because in this area the friction is less. A good mouthpiece run means careful Forming the thin-walled structure and thus the full Use of their strength.

The honeycomb pattern itself can be with respect to the longitudinal direction of the brick be arbitrarily oriented. The pattern is preferred however lay so that the heat path in the transverse direction of the brick becomes as long as possible and that is the case when webs are vertical run to the visible surfaces of the brick or two opposite corners of the hexagons to the visible surfaces are facing. The heat path extension is then around 16% compared to the arrangement with the visible surfaces parallel webs.

Hole cross sections that are as symmetrical as possible, especially the hexagonal cross section, offer as essential advantage is an almost identical stiffness in all Directions, This is a sound line, d. H. a Sound transmission in the wall level prevented. This is today one of the most important criteria for building blocks for Exterior walls.

On the other hand, there are advantages in the manufacture of the Brick. Even the dried moldings have a high Breaking strength and are therefore also ideal for surface grinding of the storage areas because they are very firm on the visible areas can be clamped.

In the case of bricks with filigree structures, especially with filigree honeycomb perforations, the body density can be reduced by porosity (Fig. 10). On the one hand, low thermal conductivity values are achieved even with weak porosity, and on the other hand, filigree structures allow relatively high porosity without significantly reducing the compressive strength. However, the porosity should not be so extreme that it reduces the compressive strength too much. With regard to the main goal of increasing the thermal insulation capacity, it is better to aim for a cullet density ≤ 1.7 kg / dm ³ or even significantly less. The use of a fibrous porosity agent is provided. The use of paper fibers is particularly advantageous. This results in fibrous, cross and transverse pores during firing which, in contrast to cavities due to granular or spherical porosity agents, give a more homogeneous structure and do not disturb the flow of force. However, it is also possible to use other fine porosity agents, e.g. B. a fine sewage sludge not contaminated with pollutants.

Furthermore, good ductility of the moist clay strand is important, which can be achieved by enriching the brick clay with a proportion of about 5 to 25% fat clay. Fat clay is a high quality clay with a high Al ₂ O ₃ content. In this way, in addition to the structurally favorable perforation pattern, the strength of the brick is positively influenced despite the large number of perforations.

The butt joint area is in known brick shapes because of the large material accumulations at this point always technically problematic. This is especially true for heat-optimized slot-hole bricks because of a thick Brick outer layer the structurally weak inner area must be balanced. In contrast, the proposed filigree small hole structure so stable, and in Cross direction not weakened that the butt side with a relatively thin outer layer can be provided.

To significantly reduce cold spots in the butt joint area, should be abandoned from the popular tongue and groove system. Instead, it is proposed that the abutting surfaces of the Brick essentially mirror-symmetrical to each other are formed, according to the hole pattern and the Course of the walls, which are the transverse direction close successive holes to the outside, Projections and depressions are formed so that the corresponding projections of two colliding Bricks come to rest against each other and the other corresponding depressions each together a cavity form. This will accumulate material in one so far Reduced dimensions not known and thermal bridges avoided. A the impact area formed in this way differs in its Structure only minimally from the rest of the hole pattern, because that is paired cavities of the wells the rest Make holes similar to holes.

The one that may be left when they collide close the thin gap and the bricks as a transfer aid at least to a small extent positively interlocking should be on each butt joint at least one tongue and one groove arranged to match be. To do this, it is sufficient that one of the two abutting surfaces of a brick a spring protruding beyond the projections is provided, which is provided in one of the anyway Wells of the adjacent tile fits. Naturally can also provide several springs on this joint be. However, one spring per brick is preferable because of the Brick then, after extrusion, on the if desired other impact surface can be stored. To light the feather to be able to insert into the corresponding specialization suggested this recess a little wider than the rest To make recesses and the laterally adjacent holes accordingly easy to deform.

To the proposed light brick when processing well It is suggested to be able to grip, in the middle area to make two grip holes, these under the Consideration of material savings by omitting one Group of holes are formed. The peculiarity of this Finger holes is that they are not independent geometric cross-sectional shape, e.g. B. circle or rectangle, have, but just follow the hole pattern, with the thickness the wall of the grip hole in comparison to the web thickness is not or is only insignificantly reinforced.

The proposed light brick is better than the known bricks of its kind in several respects, without having to accept disadvantages, particularly with regard to the load-bearing capacity. Above all, a previously achieved, favorable measured coefficient of thermal conductivity of approximately λ = 0.11 [W / m · K] can be expected. The brick inhibits the longitudinal sound conduction and is therefore particularly suitable for external walls. Regarding the brick bulk density, values of less than 0.4 kg / dm ^{3 are} within the possible range. The brick is therefore extremely light and little clay material and, accordingly, little energy, in particular when firing, is required for its production. The low weight is advantageous when processing and transporting. Lower energy tonnage saves more energy. The previously unattainable low wall weight enables the use of the bricks, for example, for partitions on unsupported ceilings, where bricks could not previously be used. When used as a load-bearing inner wall, in addition to preventing longitudinal sound conduction, sound insulation in the passage direction that is significantly better than known bricks due to the low natural vibration with the same mass must also be noted. In contrast to elongated perforated bricks, the proposed bricks can be separated better in the transverse direction, which leads to lower losses due to brick smashing in practical construction work.

Finally, there is an advantage of the brick described to add, which comes into play when the bricks come on the bearing surfaces are not ground and conventional be bricked up. The thin webs and the fibrous ones Porosity inclusions have the consequence that the webs when Cutting be warped. Forms on the cut edges a beard that shows the small openings of the holes partially covered, but at least its clear cross-section decreased. This leads to an unprecedentedly low level Mortar incidence, d. H. that the mortar is essentially in the Bearing joint remains and only a tiny part in the holes come in.

Fig. 1

zwei Teilstücke von aneinandergefügten Leichtziegeln mit Wabenlochung in Draufsicht in natürlicher Größe,

Fig. 2

einen Horizontalschnitt (Lochbild) eines ganzen Ziegels in kleinerem Maßstab,

Fig. 3

zwei Teilstücke von aneinandergefügten Leichtziegeln mit Rundlochung in Draufsicht in schematischer Darstellung,

Fig. 4

eine entsprechende Darstellung mit einer abgeflachten Sechsecklochung,

Fig. 5

eine entsprechende Darstellung mit einer versetzten Quadratlochung,

Fig. 6

eine entsprechende Darstellung mit einer Recktecklochung,

Fig. 7

ein anderes verwendbares Lochmuster mit regelmäßig angeordneten quadratischen Löchern,

Fig. 8

mit versetzten Rechteck-Löchern,

Fig. 9

mit Löchern von gleichzeitig dreieckigem Querschnitt und

Fig. 10

eine Darstellung von berechneten Kennwerten des in Fig. 2 dargestellten Ziegels

Embodiments of the invention are explained below with reference to the drawing. It shows

Fig. 1

two sections of light bricks joined together with perforated honeycomb in top view in natural size,

Fig. 2

a horizontal section (hole pattern) of an entire brick on a smaller scale,

Fig. 3

two sections of light bricks joined together with round perforation in plan view in a schematic representation,

Fig. 4

a corresponding representation with a flattened hexagon perforation,

Fig. 5

a corresponding representation with an offset square perforation,

Fig. 6

a corresponding representation with a rectangular perforation,

Fig. 7

another usable hole pattern with regularly arranged square holes,

Fig. 8

with offset rectangular holes,

Fig. 9

with holes of triangular cross section and

Fig. 10

a representation of calculated parameters of the brick shown in Fig. 2

1 are two bricks 1 and 2 with their butt sides to each other. There is a special groove 3 on brick 1 and one Spring 4 shown on brick 2. The brick 2 is a partial enlargement of the brick shown completely in Fig. 2. The spring 4 is only once on an abutment surface of the brick available. One side wall (visible side) of the brick is 5 designated. This also indicates the longitudinal direction of the bricks.

The bricks have a hexagonal honeycomb pattern, whereby the hexagons are arranged so that two each other opposite corners to the side walls 5 show and a Part of the webs 6 is perpendicular to the side walls. The The thickness of the webs in this is preferred Embodiment slightly more than 2 mm. The hole percentage at this honeycomb pattern is 66.5%. On the side walls 5 are the hexagon holes slightly blunted.

The walls 7 of the bricks on the butt sides follow the Outer wall sections of those hexagon holes that the last, transverse row of holes in each tile form. This creates projections 8 and depressions 9. The thickness of the walls 7 changes between about 3 and 5.5 mm is therefore less than three times the web thickness. The Spring 4 protrudes over the projections 8. You see from that Area of this single tongue 4 and the associated groove 3 once off, so are the impact walls 7 of the two bricks designed mirror-symmetrical to each other. The one another corresponding projections 8 lie against each other. The one another corresponding recesses 9 form both bricks with each other a hexagonal cavity 10. The abutting sides of the two bricks experience irregularities only in the area of tongue and groove, which is close to a Side wall 5 are arranged. The groove 3 is somewhat stronger expanded than the other depressions 9. The spring 4 contains a cavity 11 in the form of a partial cut hexagons.

The cavities 10 and 11 act from a certain distance looks about like the other hexagon holes, so that the Joint area continues the honeycomb structure and thereby has an almost undiminished thermal insulation effect.

The brick shown completely in Fig. 2 has 21 rows of holes. The hole row spacing a is approximately 14 mm. The only wedge-shaped spring 4 fits an identical neighboring tile in one of the three arranged near the side walls 5 Grooves 3, 12, 13.

The advantage of this unusual arrangement of only one spring 4 or alternatively, there is more than one spring on one end in that the freshly extruded still soft molding placed on its springless butt side without damage and can be promoted. It has been shown that at so small web thicknesses the stability of the structure Lateral position is not sufficient to carry your own weight, because in this case the sloping webs lead to Gravity direction form an angle of 60 ° and itself therefore can bend. There is a risk that the In this position, the molding partially collapses. On the other hand, the rigidity is completely sufficient if the Molding is placed on the butt surface. In this situation the sloping webs form an angle of only 30 ° with the Direction of gravity and thus have a higher Kink resistance. The weight of the molding is based on the front surfaces of the lying in a common transverse plane Projections 8 evenly distributed.

Finally, there are two with this lightweight brick Handle holes 14 to mention that in the middle brick area Are arranged one behind the other in the longitudinal direction. Every finger hole 14 was created by omitting seven hexagon holes.

The brick shown is 248 mm long and 300 mm wide (Thickness of the brick wall). The clear width of the honeycomb (perpendicular to the webs) is 14 mm. The thickness of the Side walls 5 is 7 mm and the thickness of the walls 7 in Direction of impact measured 5.5 mm. The two faces are in the formed essentially mirror-symmetrical to each other. Of course you can also use this hole pattern Brick for thicker or thinner walls according to the national standards are designed, which is why correspondingly more or less longitudinal rows of holes are to be provided.

The brick density class 0.5 kg / dm ^{3 is} achieved with this brick. In relation to corresponding known bricks that are offered on the German market and belong to the bulk density class 0.8 kg / dm ³ , the unit weight is reduced from 13.5 kg to 9 kg. The same static pressure resistance is nevertheless achieved. The airborne sound absorption capacity in all spatial directions is superior to that of all previously known perforations.

Computer calculations performed by the Federal Institute for Materials Testing (BAM) in Berlin using the finite element method have led to the results shown in FIG. 10. On the basis of four different cullet qualities, the web thickness and the associated proportion of holes in a 300 mm wide honeycomb high brick were varied in a manner similar to FIG. 2 and the heat transfer coefficient k [W / m ² · K] was calculated in each case. The cullet materials are each characterized by their thermal conductivity, which lies between λ _cullet = 0.40 [W / m · K] and λ _cullet = 0.25 [W / m · K]. The lower value corresponds to a higher porosity. It can be seen that in the case of a clay which is not very porous and in the interest of high compressive strength and with a web thickness of 2 mm, a heat transfer coefficient k = 0.38 [W / m ² · K] is achieved. In the case of the 30 cm thick brick according to FIG. 2, this corresponds to an extremely low coefficient of thermal conductivity λ = 0.12 [W / m · K].

The bricks with a round hole pattern according to FIG. 3 show that same principle of the training of the face as well Projections 8 'and depressions 9' are formed as they are in the case of a cut from the Hole pattern result. The protrusions have flat sections, the depressions are circular. The radius of curvature the spring 4 'corresponds approximately to the radius of the round holes, the radius of curvature of the corresponding groove is somewhat larger held.

The hole shape of the example according to FIG. 4 is an in Brick corner shortened corner. Are here too Projections 8 ", depressions 9" and a spring 4 " distinguish, which are similar in shape to the holes.

5 also exists adjacent projections and corresponding, depressions each forming a common cavity. At The spring shown was from the rest of the hole pattern deviated as the tongue and its corresponding groove has wedge-shaped flanks, which is a corresponding Changes in the neighboring holes.

6 are in contrast to all In the previous examples, the rows of holes did not face each other offset, rather the webs form a cross lattice. Nevertheless are corresponding projections on the abutting surfaces 8 '' 'and depressions 9' '' formed. The tabs included holes 15 shortened to about half the length, so that the of about two depressions formed common cavity 10 '' ' is the size of a normal corner hole. Here too the spring 4 '' 'is formed with wedge-shaped flanks.

1

Ziegel

2

Ziegel

3

Nut

4

Feder

4'

Feder

4''

Feder

4'''

Feder

5

Seitenwand

6

Steg

7

Wand

8

Vorsprung

8'

Vorsprung

8''

Vorsprung

9

Vertiefung

9'

Vertiefung

9''

Vertiefung

10

Hohlraum

10'''

Hohlraum

11

Hohlraum

12

Nut

13

Nut

14

Griffloch

15

Loch

a

Abstand

FIGS. 7 to 9 give further hole pattern examples which can be used in bricks according to the invention.

1

brick

2nd

brick

3rd

Groove

4th

feather

4 '

feather

4 ''

feather

4 '''

feather

5

Side wall

6

web

7

wall

8th

head Start

8th'

head Start

8th''

head Start

9

deepening

9 '

deepening

9 ''

deepening

10th

cavity

10 '''

cavity

11

cavity

12th

Groove

13

Groove

14

Finger hole

15

hole

a

distance

Claims (7)

1. A high-hole lightweight brick with two abutting faces which, after the wall has been built, are towards the horizontally adjacent bricks, with two visible surfaces (5) and with a hole pattern comprising a plurality of longitudinally extending rows of holes and webs (6) which separate the holes from one another, the ratio of the largest to the smallest inside diameters of the cross-section of a single hole being between 1 : 1 and 1 : 2.5, the distance (a) between the rows of holes being at most 22 mm, the pattern of holes being an hexagonal honeycomb hole pattern and the honeycomb pattern is so disposed that honeycomb webs (6) are at right-angles to the visible surfaces (5) of the brick, characterised by the following features:

   a) the thickness of the webs (6) amounts to 1.5 mm to a maximum of 4 mm;

   b) the proportion represented by the holes amounts to at least 50%;

   c) the raw density of the refuse is ≤ 1.7 kg/cu.dm and preferably 1.5 kg/cu.dm;

   d) a fibrous porous-making agent is used.
2. A high-hole lightweight brick according to claim 1, characterised by paper fibres being used as the porous-making agent.
3. A high-hole lightweight brick with two abutting surfaces which, after the wall has been built, are towards the horizontally adjacent bricks, with two visible surfaces (5) and with a hole pattern comprising a plurality of longitudinally extending rows of holes and webs (6) which separate the holes from one another, the ratio of the largest to the smallest inside diameters of the cross-section of a single hole being between 1 : and 1 : 2.5, the distance (a) between the rows of holes being at most 22 mm, characterised by the following features:

   a) the thickness ofthe webs (6) amounts to 1.5 mm to a maximum of 4 mm;

   b) the proportion represented by the holes amounts to at least 50%;

   c) the raw density of the refuse is ≤ 1.7 kg/cu.dm and preferably 1.5 kg/cu.dm;

   d) the abutting surfaces are substantially mirror-symmetrical in respect of one another, whereby according to the hole pattern and the course of the walls (7) which seal off the outside of holes which follow one another in the transverse direction, so projections (8) and depressions (9) are formed so that the mutually corresponding projections (2) on two abutting bricks (1, 2) come to bear on one another while the mutually corresponding depressions (9) respectively and jointly form a cavity (10),

   e) at least two of the abutting surfaces have, projecting beyond the projections, a tongue (4) which fits into one of the depressions on the abutting neighbouring brick (1) which form a groove (3, 12, 13),

   f) a fibrous porous-making agent is used.
4. A high-hole lightweight brick according to claim 3, characterised in that a variety of tongues are provided on each abutting surface.
5. A high-hole lightweight brick according to claim 3, characterised in that the groove (3) which co-operates with the tongue (4) on the neighbouring brick is somewhat wider than the other depressions (9), the holes laterally adjacent the groove (3) being slightly deformed.
6. A high-hole lightweight brick according to claim 3, characterised in that its walls (7) are on the abutting surfaces at most three times the thicknesses of the webs (6).
7. A high-hole lightweight brick according to one of the preceding claims, characterised in that in the central area there are two handle holes (14) formed by the omission of a group of holes.

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