DIMPLED SHEET

Information

  • Patent Application
  • 20080086958
  • Publication Number
    20080086958
  • Date Filed
    October 17, 2007
    16 years ago
  • Date Published
    April 17, 2008
    16 years ago
Abstract
A dimpled sheet, with a flat area and a plurality of dimples protruding over the flat area, each having a dimple casing and a dimple cover, wherein contact surfaces for placement of the dimpled sheet against a subsurface are formed on the side of the dimples by the outer sides of the dimple covers. The proportion of the total contact surface of all dimples of the total surface of the dimpled sheet is greater than 35%, with the base surface of the dimpled sheet being formed from the flat area and the base surface of all dimples at the level of the flat area. The dimpled sheet has a protection coefficient (PC) of more than 10.000, whereby the PC is:
Description

BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 shows a section from a cross-sectional view of a dimpled sheet, and



FIGS. 2-23 show sections of top views of the contact surfaces of dimpled sheets according to the invention formed by the dimple covers of the dimples, each in schematic representation.





DETAILED DESCRIPTION

The dimpled sheet 1 has a flat area 2 and a plurality of dimples 5 protruding over the flat area 2 and each having a dimple casing 3 and a dimple cover 4. On the side of the dimples 5, contact surfaces for placement of the dimpled sheet 1 against a bitumen sheet 6 are formed by the outer side A of the dimple covers 4, with said bitumen sheet 6 being applied to the outside of a building wall 7. The outer side A is the outer contact surface of a dimple cover.


In the dimpled sheet 1 depicted in FIG. 1, the dimples 5 have a truncated cone shape and have a substantially level dimple cover 4. The dimples 5 can also have the shape of a truncated pyramid, a cone, a cylinder or a rectangle. As will readily be understood, the dimple cover 4 can also have recesses in order to increase the rigidity of a dimple 5. For example, in this connection, the dimple cover 4 can have a circular or annular or even an n-cornered contact surface, with the contact surface of a dimple 5 being formed by the surface components of the dimple cover 4 acting against the bitumen sheet 6.


In the dimpled sheet 1 depicted in FIG. 1, a provision is made that the proportion of the total contact surface that is formed by the dimple covers 4 of all dimples 5 lying against the bitumen wall 6 is greater than 35%, preferably between at least 45 to 50%, of the base surface of the dimpled sheet 1, with the base surface of the dimpled sheet 1 being formed by the flat area 2 and the base surface of all dimples 5 at the level of the flat area 2. In this connection, the flat area 2 describes the entire surface of the level areas of the dimpled sheet 1 arranged between the dimples 5. As a result, the dimpled sheet 1 illustrated in FIG. 1 has a relatively large total contact surface to the subsurface. This makes it possible to ensure that, after the filling of a construction pit with fill dirt 8, either no or only slight penetration of the dimples 5 into the bitumen sheet 6 can occur due to the fill pressure brought about by the fill dirt 8. The danger of damaging the bitumen sheet 6 is hence reduced considerably. At the same time, it is ensured by the inwardly oriented dimples 5 that the dimpled sheet 1 is torn off or partially shifted downward during filling of the fill dirt 8 into a pit (not depicted) adjacent to the building wall 7. Moreover, the removal of water through the hollow spaces 9 arranged between the dimples 5 is ensured by the inwardly oriented dimples 5, with the hollow spaces 9 forming air cushions which have a heat-insulating effect and permit vapor pressure compensation. In addition, the individual hollow spaces of the dimpled sheets are connected to each other, although it is also possible in principle that a plurality of hollow spaces that are separated from each other can be provided.


In FIGS. 2 to 23, contact surfaces of dimpled sheets 1 for one cross-section of the respective dimpled sheet 1 are respectively depicted for the sake of example, with the contact surfaces being formed by outer sides of dimple covers 4 of a plurality of dimples 5. The base or cross-sectional surfaces of the dimples 5 at the level of the flat area 2 are not shown. Here it is possible that the dimples 5 have the same cross-section over the entire dimple height, as is the case in cylindrical or rectangular dimples 5, for example. As will be readily understood, the dimples 5 can also have a cross-section which changes over the dimple height, as can be the case with truncated cone- or truncated pyramid-shaped dimples 5.


In the embodiment of a dimpled sheet 1 depicted in FIG. 2, the formed contact surfaces are preferably spaced equally apart from each other in all directions of the dimpled sheet 1. Here, according to FIG. 2, the dimples 5 have square contact surfaces, and the dimples 5 as such can be shaped in the form of a truncated pyramid or be rectangular. In dimples 5 with square contact surfaces, a proportion of the total contact surface of greater than 50% of the total surface of the dimpled sheet 1 is achieved, for example, if every dimple cover 4 has an edge length of approx. 11 mm, with a distance between neighboring dimple covers 4 of approx. 4 mm, respectively.


In the embodiment shown in FIG. 3, the contact surfaces of the dimples 5, in turn, have the same spacing from each other in all directions of the dimpled sheet 1 at least at the level of the dimple covers 4, with the dimples 5 having rectangular contact surfaces. In this way, the total contact surface can be increased further while maintaining the intermediate spacing of approx. 4 mm.


Moreover, in the dimpled sheet 1 depicted in FIG. 3, a plurality of rows of dimples 10, 11 are provided which are arranged perpendicularly to each other and each having a plurality of dimples 5, with the dimples 5 of a row of dimples 10, 11 being respectively arranged axially on the middle longitudinal axis of the respective row of dimples 10, 11. In the embodiment portrayed in FIG. 3, a raster- or lattice-like arrangement of the dimples 5 on the dimpled sheet 1 is further provided. By contrast, the embodiment shown in FIG. 4 is such that the dimples 5 of a first row of dimples 10 and the dimples 5 of at least one other adjacent row of dimples 10a running parallel to the first row of dimples 10 are arranged in a staggered manner with respect to each other in the direction of the middle longitudinal axis of the neighboring row of dimples 10, 10a.


In the dimpled sheets 1 depicted in FIG. 3 and FIG. 4, the longitudinal and transverse sides of the dimple covers 4 are oriented parallel to the longitudinal and transverse sides of the dimpled sheet 1. It goes without saying that it is of course also possible to embody the longitudinal and transverse sides of the dimple covers 4 and hence the contact surfaces of the dimpled sheet 1 such that they run perpendicularly to the longitudinal and transverse sides of the dimpled sheet 1.


Since, as the size of the dimples 5 or of the contact surfaces increases, their compressive strength decreases, dimples 5, 5a, 5b can be arranged regularly, particularly alternatingly, next to each other with different-sized contact surfaces and/or different shapes of the contact surfaces. This is shown, for example, in FIGS. 5 to 7. For example, a provision is made in FIG. 5 to arrange dimples 5 with larger contact surfaces and dimples 5a with relatively smaller contact surfaces next to each other, with the dimples 5 each having dimple covers 4 with a square contact surface and the dimples 5a each having dimple covers 4 with a rectangular contact surface. Here, the contact surface of a dimple 5a is approx. 50% of the contact surface of a dimple 5.


In FIG. 6 and FIG. 7, other dimpled sheets 1 are depicted which show the possible combinations of larger dimples 5 with smaller dimples 5a, 5b. The illustrated embodiments show that dimples 5 can be respectively provided with a first contact surface and other dimples 5a, 5b can be respectively provided with another contact surface deviating from the first contact surface in order to enlarge the total contact surface of the dimpled sheet 1, with the dimples 5 and the other dimples 5a, 5b having contact surfaces of different shapes and/or sizes. As a result, two, three or even more types of dimple of different shapes and/or sizes can be provided in order to make available a comparatively larger total contact surface of the dimpled sheet 1 to the subsurface.


In principle, a total contact surface proportion of greater than 50% of the base surface of the dimpled sheet 1 can also be ensured with dimples 5 that have circular contact surfaces, with cylindrical dimples 5 having a higher load capacity than dimples 5 of an n-cornered shape. One possible sample embodiment of a dimpled sheet 1 with dimples 5 that have circular dimple covers 4 is shown in FIG. 8, for example. In the dimpled sheet 1 depicted in FIG. 8, the condition indicated below must preferably be met in order to ensure a sufficient total contact surface proportion of greater than 50%:





[π·d2/4]/[(d+a1)·(d+a2)]>0,5


Even with dimples 5 with circular contact surfaces, an increase of the load capacity of the dimpled sheet 1 can be achieved by having larger dimples 5 arranged adjacent to smaller dimples 5a, each with respect to the size of the contact surfaces or the size of the dimple covers 4. This is shown, for example, in FIGS. 9 and 10. As also follows from FIGS. 9 and 10, the larger dimples 5 can be arranged in a regular raster, with the other, smaller dimples 5a being disposed in empty spaces of the raster.


Moreover, dimples 5 that have contact surfaces having one shape and/or size can have other dimples 5a that have contact surfaces having another shape and/or size arranged peripherally in the manner of a frame. This is shown, for example, in FIGS. 9 and 11.


In the dimpled sheet 1 depicted in FIG. 11, dimples 5 with dimple covers 4 are provided which form square contact surfaces. The dimples 5 are arranged here in the manner of a frame about a dimple 5a whose dimple cover 4 forms a circular contact surface. The combination of dimples 5, 5a with different contact surfaces is advantageous, since dimples 5 with an n-cornered contact surface ensure a larger surface utilization and dimples 5a with circular contact surface ensure a greater pressure load capacity. Further examples of embodiments of dimpled sheets 1 having dimples 5, 5a, 5b with contact surfaces of different sizes and/or shapes or contours are shown in FIGS. 12 to 20. In the dimpled sheet 1 depicted in FIG. 20, the condition indicated below must preferably be met in order to ensure a sufficient total contact surface proportion of greater than 50%:






[π·d
2/4+4·x1x2]/[(x2+2·a1+x1)·(x2+2·a2+x1)]>0,5


Dimpled sheets 1 are shown in FIGS. 13 and 16, each with 3 different types of dimples, with the types of dimple differing in terms of the size and shape of the contact surfaces formed by the dimple covers 4.


In another embodiment of a dimpled sheet 1, a provision can be made that the contact surfaces of neighboring dimples 5a, 5b formed by the dimple covers 4 have contours that are complementary to each other, at least in sections. For example, according to FIG. 21, three different types of dimple are provided in dimples 5, 5a, 5b, with one dimple 5b being framed by a circular contact surface of four dimples 5a, each having contact surfaces with inwardly curved longitudinal sides 12. This results in an annular space 13 which is bounded toward the inside by the outer edge of the dimple cover 4 of the dimple 5b and toward the outside by the inwardly curved longitudinal sides 12 of the dimple covers 4 of the neighboring dimples 5a. By virtue of the mutually complementary contact surfaces of the dimples 5a, 5b, an even greater surface utilization can be ensured.


Another possibility for enlarging the total contact surface of the dimpled sheet 1 consists in providing dimples 5 with oval or ellipsoid contact surfaces, with the contact surfaces each preferably being narrowed in the middle area and the dimples 5 being arranged such that neighboring contact surfaces, in turn, have a complementary contour to each other at least in sections. This is shown, for example, in FIG. 22. A combination of the dimples 5 shown in FIG. 22 with other dimples 5a having circular contact surfaces is also possible and contributes to the enlargement of the total contact surface. This is illustrated in FIG. 23.


It is not shown that the dimple covers 4 can also have an n-cornered shape, for example as a hexagon, octagon or dodecagon. Moreover, as will readily be understood, the dimple covers 4 of the dimples 5, 5a, 5b can also have recesses, resulting in annular contact surfaces, for example.


Finally, it should be pointed out that dimples with different extensions in the longitudinal and transverse direction can also be arranged such that they have reciprocal directional preferences, which is shown in FIGS. 6, 20 and 21, for example. By reciprocal directional preferences is meant, for example, that rectangular dimples can be arranged both standing and lying. This can also be the case, for example, in the embodiments shown in FIGS. 3, 4, 5, 7, 18, 19 and 23.


At a preferred embodiment of the present invention the total contact surface CS has 36% and the dimple height DH is 8,2 mm. With these values the protection coefficient PC has an amount of 10.627,2.

Claims
  • 1. Dimpled sheet, particularly for construction purposes and preferably for use as foundation wall protection or drainage sheeting, with a flat area and a plurality of dimples protruding over the flat area, each having a dimple casing and a dimple cover, wherein contact surfaces for placement of the dimpled sheet against a subsurface are formed on the side of the dimples by the outer sides of the dimple covers, wherein the proportion of the total contact surface of all dimples of the total surface of the dimpled sheet is greater than 35%, wherein the base surface of the dimpled sheet is formed from the flat area, having a protection coefficient (PC) of more than 10.000, whereby the protection coefficient (PC) is defined by the formula PC=(CS)2×DH
  • 2. Dimpled sheet as set forth in claim 1, wherein the protection coefficient (PC) is more than 12.000 and especially more than 16.000,00.
  • 3. Dimpled sheet as set forth in claim 1, wherein a compressive strength per DIN 53454 of between 50 to 1500 kPa, preferably between 150 to 1000 kPa, and particularly between 300 to 700 kPa is provided.
  • 4. Dimpled sheet as set forth in claim 1, wherein an sd value per EN 1931 of greater than 2 m, preferably greater than 50 m and especially preferably greater than 100 m and particularly greater than 500 m is provided.
  • 5. Dimpled sheet as set forth in claim 1, wherein the total contact surface of all dimples is up to 80% of the base surface of the dimpled sheet, preferably between 40 and 70% and particularly between 45 and 60%.
  • 6. Dimpled sheet as set forth in claim 1, wherein the free volume between the dimples lies in the range between 500 to 10,000 mm3/m2, preferably between 1000 to 7000 mm3/m2 and particularly between 1500 and 4000 mm3/m2.
  • 7. Dimpled sheet as set forth in claim 1, wherein dimples each with a first contact surface and other dimples each with another contact surface deviating from the first contact surface are provided and that the dimples and the other dimples have contact surfaces of different shapes and/or sizes.
  • 8. Dimpled sheet as set forth in claim 1, wherein the dimples and the other dimples are arranged alternatingly next to each other, in each case at least with respect to the level of the contact surfaces.
  • 9. Dimpled sheet as set forth in claim 1, wherein the dimples are arranged in a regular raster and that the other dimples are provided in empty spaces of the raster, in each case at least with respect to the level of the contact surfaces.
  • 10. Dimpled sheet as set forth in claim 1, wherein the dimples are framed by the other dimples, in each case at least with respect to the level of the contact surfaces.
  • 11. Dimpled sheet as set forth in claim 1, wherein the dimples with respectively circular contact surfaces and other dimples are each provided with an n-cornered contact surface.
  • 12. Dimpled sheet as set forth in claim 1, wherein the dimples and neighboring other dimples have contact surfaces which are complementary to each other at least in sections.
  • 13. Dimpled sheet as set forth in claim 1, wherein the dimples are each provided with an ellipsoid contact surface and that each contact surface preferably has a narrowing in its middle area.
  • 14. Dimpled sheet as set forth in claim 1, wherein the dimple height is between 3 to 15 mm, particularly between 3 to 10 mm, more particularly between 3 to 7 mm.
  • 15. Dimpled sheet as set forth in claim 1, wherein the contact surfaces have an edge length or a diameter of 3 to 30 mm.
  • 16. Dimpled sheet as set forth in claim 1, wherein the wall thickness of the dimples is between 0.1 to 1.0 mm, particularly between 0.3 to 0.6 mm.
Priority Claims (2)
Number Date Country Kind
10 2006 049 450.4 Oct 2006 DE national
10 2006 052 257.5 Nov 2006 DE national