Block with multifaceted bottom surface

Information

  • Patent Grant
  • 6250850
  • Patent Number
    6,250,850
  • Date Filed
    Thursday, August 19, 1999
    25 years ago
  • Date Issued
    Tuesday, June 26, 2001
    23 years ago
Abstract
A block for use in constructing a retaining wall having a bottom with a non-planar portion which creates a gap between the bottom surface and the top surface of a lower course of similar blocks when the block is placed thereon. This gap assists the block in resting on the lower course of blocks by providing a space where small amounts of rubble and dirt may exist without interfering with the stacking of the blocks. Preferably, the block's bottom surface further comprises a plurality of grooves which provide additional clearance in the gap for larger stones. It is envisioned that these grooves be “V” shaped, thereby having angled walls which act to funnel the larger stones into an area when the block is being placed on a lower course of similar blocks.
Description




BACKGROUND OF THE INVENTION




This invention relates generally to the construction of retaining walls used in landscaping applications. Such walls are used to provide lateral support between differing ground levels where the change in one elevation to the other occurs over a relatively short distance, thereby reducing the possibility of erosion and landslides. Retaining walls can be both functional and decorative and range from small gardening applications to large-scale construction. They are constructed of a variety of materials and shapes. Some have been constructed of wood timbers, others of rock in a natural form (such as limestone). Still others have been constructed of manufactured aggregate or concrete blocks. The present invention relates to a manufactured block.




Constructing a fit and true retaining wall can be an arduous endeavor. In addition to laying a level first course on ground which is usually located at the foot or in the side of a steep embankment, the builder must ensure that each subsequent course is level. An error made in a lower course usually gets exaggerated as higher courses are stacked above it. As a wall made of blocks necessarily develops somewhat of a grid-like appearance, interruptions or undulations in the lines of the wall become readily apparent to the human eye.




One particular problem the prior art has failed to overcome is developing a retaining wall block shaped to avoid these undulations and interruptions which are caused by blocks being stacked on dirt or debris found on the upper surface of the lower course of blocks. Dirt presents itself as a result of the fill material used to fill the gap between the rear of the wall and the earth it is being built to retain. This fill material usually consists of small, coarse rocks. They serve as a barrier between the earth and the wall and prevent wet earth from seeping through the bricks of the wall during inclement weather. Present wall building methods include laying a course of blocks, filling the space behind the course with fill material, packing the fill material, and carefully sweeping the dirt off of each completed course prior to the addition of the next course. This final, sweeping step is time consuming but necessary to ensure the next course of blocks lies flat on the lower course.




Some larger blocks incorporate continuous cavities that extend from their bottom surface to their top surfaces. These cavities are intended to reduce the amount of material required to form the block, thereby reducing its cost and weight, and also allow an area to be filled with fill material once a course is finished. At first blush it would appear that, because the presence of cavities reduces the surface area of the top and bottom of the block, they would also serve to decrease the area for interference by small stones and debris between courses. However, because the cavities are filled with fill material, the fill material spills over the upper surfaces and exacerbates, rather than alleviates, the problem. Furthermore, smaller blocks cannot incorporate cavity portions without jeopardizing their structural integrity.




The inability of smaller blocks to accommodate cavity portions creates further problems. Making a solid block out of concrete results in a dense rock which is heavy for its relatively small size. Working with these rocks can become cumbersome. The absence of cavities or interruption in the side walls makes these blocks difficult to lift. They have few areas which lend themselves to easy gripping and lifting. This becomes an important consideration in light of the number of blocks that must be lifted and set in place during the construction of even a relatively small retaining wall.




It would be desirable to develop a retaining wall block shaped to accept a certain amount of dirt and debris from course to course without adversely affecting the overall structure and aesthetics of the resulting wall. It would also be desirable to devise a small retaining wall block which is has a reduced unit weight due to the absence of block material in an area that will not adversely affect the strength of the block, nor its appearance. Finally, it would be desirable to provide a small retaining wall block which is relatively easy to grasp and pick up off of a stack of similar blocks.




SUMMARY OF THE INVENTION




The present invention advantageously provides a block for use in building a retaining wall that produces a level course of blocks, despite the presence of a small amount of debris on the lower course of blocks.




The present invention is also advantageous in that it provides a relatively small block with material removed from strategic locations to provide a block which is lighter than it would have been had it been solid, yet the removal of material has not adversely affected the strength of the block, nor the appearance of the resulting wall.




The present invention advantageously provides a block which has areas for a person building a retaining wall to grasp the block when lifting the block off of a stack of such blocks and placing the block on a lower course of blocks in the wall being constructed.




The instant invention relates to a retaining wall block so shaped that when placed on top of a lower course of similar blocks, it lies flat despite the inevitable presence of dirt, small stones, and other debris. This feature alleviates the time-consuming step of meticulously cleaning the top of each course of blocks before the next course may be laid on top of it.




The block generally comprises a continuous top surface, side surfaces extending from the top surface, front and back surfaces extending from the top surface and spanning laterally between the side surfaces and a bottom surface integral with the front, back and side surfaces.




In order to achieve the tolerance of small stones and debris between courses, a portion of the bottom face of the block of the present invention is non-planar, more specifically, concave. This concave surface significantly reduces the area for block to block contact between successive courses. Preferably, this non-planar portion covers more than one half of the area of the bottom surface of the block. It also functions to provide an area of clearance or a gap between the stones where debris can migrate without causing interference or instability between courses. The concave portion is preferably shaped to form a portion of a cylinder and extends from one side surface to the other. Alternatively, the concave portion could be shaped to form a portion of a sphere or any other shape.




In addition to the concave portion of the bottom surface, the present invention further comprises a plurality of grooves formed in the bottom surface and preferably extending transversely of the bottom surface between the front and back surfaces. The grooves preferably are angled inwardly to form an inverted “V” shape when the block is given its intended orientation. The grooves allow spaces of increased clearance for larger stones. The grooves preferably comprise two opposed surfaces of a predetermined width extending the length of the groove. The two surfaces are angled to form a “V” shape and meet to form an angle α. The angled walls of the grooves not only reduce the weight of the block, but also act to funnel larger stones into the grooves, thereby positioning them into an area of maximum clearance. Alternatively, the first and second surfaces may be joined by a third, curved or flat, surface juxtaposed between the first and second surfaces. Such a third surface would give the groove an inverted “U” shape. The grooves are cut into the block and have a set depth which follows the irregular contour of the non-planar bottom surface.




Preferably, the bottom surface further comprises one or more downward projections proximate the rear surface and having an abutting surface which contacts the rear surface of a lower course of blocks when the block is stacked thereon. It is envisioned that the abutting surface is either parallel to the rear surface of the block, or forms an angle P with the rear surface. These projections create an automatic and uniform setback among successive courses of blocks so that the resulting retaining wall is angled rearwardly. This adds resistive strength to the wall against the natural forces exerted on the wall by the earth the wall is retaining.











DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a block of the present invention, looking up at the bottom to reveal the details of the bottom surface;





FIG. 2

is a cross sectional view of the block of the present invention taken along lines


2





2


of

FIG. 1

;





FIG. 3

is a cross sectional view of the block of the present invention taken along lines


3





3


of FIG.


1


and shown with other blocks in phantom, stacked, as in a retaining wall;





FIG. 4

is a bottom plan view of the block of

FIG. 1

;





FIG. 5

is a perspective view of the block shown in

FIG. 1

in a stacked relationship with other blocks, as in a wall, and showing debris resting on a lower course of blocks and accommodated for by the concave area of the bottom surface of the block of the present invention;





FIG. 6

is a perspective view of an alternative embodiment of the present invention, looking up at the bottom to show the detail of the bottom surface;





FIG. 7

is a sectional elevational view taken along lines


7





7


of

FIG. 6

;





FIG. 8

is an end elevational view of a block of the embodiment shown in

FIG. 6

, in stacked relation, as in a wall, with other blocks shown in phantom; and,





FIG. 9

is a bottom plan view of a block of the embodiment shown in FIG.


6


.











DETAILED DESCRIPTION




These and other objectives and advantages of the invention will appear more fully from the following description, made in conjunction with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views. And, although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined only by the claims.




Referring now to

FIG. 1

, there is shown a retaining wall block


10


having a front surface


12


, side surfaces


14




a


and


14




b


extending rearwardly from front surface


12


and integral with rear surface


16


. Top surface


18


is generally planar and continuous across its extents. Top surface


18


extends from side surface


14




a


to side surface


14




b


, and from front surface


12


to rear surface


16


. Preferably, top surface


18


is generally perpendicular to side surfaces


14




a


and


14




b


, and also to front surface


12


and rear surface


16


.




In the preferred embodiment shown in the Figures, front surface


12


comprises three parts,


12




a


,


12




b


, and


12




c


. Part


12




c


is generally parallel to rear surface


16


and lies between parts


12




a


and


12




b


. Parts


12




a


and


12




b


are angled such that the extend from part


12




c


and diverge rearwardly to meet side surfaces


14




a


and


14




b


, respectively. Parts


12




a


,


12




b


, and


12




c


are shown as split faces as opposed to formed faces. Creating a face with a rock splitter results in an irregular, more natural appearing surface. Also shown in the Figures is a rear surface


16


which has a smaller width than front surface


12


such that side surface


14




a


and


14




b


must converge rearwardly in order to be integral with rear surface


16


. This shape allows the construction of straight, concave, convex, or serpentine walls without interrupting the relatively uniform appearance created by the front surfaces


12


of a plurality of blocks


10


forming a wall.




Bottom surface


20


extends from front surface


12


to rear surface


16


and from side surface


14




a


to side surface


14




b


. Bottom surface


20


includes concave, or non-planar portion


22


. Concave portion


22


is depicted in

FIGS. 1

,


3


and


4


as a relatively cylindrical indentation in bottom surface


20


, extending from side surface


14




a


to side surface


14




b


. Preferably, portion


22


does not extend forward of where side surfaces


14




a


and


14




b


meet parts


12




a


and


12




b


of front surface


12


. This way concave portion


22


is not visible in a completed wall, regardless of whether the wall is straight, concave, convex, or serpentine.




Allowing concave portion


22


to extend from side surface


14




a


to side surface


14




b


creates a gap


24


between the bottom surface


20


and the upper surface of a lower course of blocks when block


10


is placed thereon. This gap


24


may be used for ease in picking the block up and setting the block down. Also, as shown in

FIGS. 1

,


3


and


4


, concave portion


22


extends rearwardly but ends forward of downward projection


34


, which is described in more detail below. Ending the concave or, non-planar portion


22


forward of downward projection


34


provides another flat surface for block to block contact to assist in the leveling and stabilization of block


10


on a lower course of blocks.




Alternatively, it is envisioned that concave portion


22


be an indentation of any shape, such as the generally spherical shape of the embodiment shown in

FIGS. 6-9

. Preferably, portion


22


is large enough to occupy at least 30 percent, more preferably on the order of 50 to 75 percent, of the surface area of bottom surface


20


.




In a preferred embodiment, bottom surface


20


also includes at least one, preferably a plurality of, grooves


28


. As shown in

FIG. 2

, grooves


28


are preferably “V”-shaped and extend from the bottom surface into the block toward top surface


18


. In the embodiment depicted in

FIGS. 1 and 2

, grooves


28


are spaced generally equidistant from each other and oriented such that they extend from front to back generally across the non-planar portion


22


. It is envisioned that grooves


28


could be located generally anywhere across bottom surface


20


. It is preferred, however, that grooves


28


do not intersect front surface


12


so that grooves


28


remain hidden from view when block


10


is part of a completed wall.




Grooves


28


having the preferred “V” shape generally comprise at least a first surface


30


and a second surface


32


. First surface


30


extends from bottom surface


20


and is integral with second surface


32


. Second surface


32


extends from first surface


30


to bottom surface


20


thereby forming an angle α between first surface


30


and second surface


32


as seen in

FIGS. 2 and 7

. Angle a is preferably less than 180 degrees. Alternatively, first surface


30


and second surface


32


could be joined by a third surface (not shown in the Figures) which extends along the length of the groove and is juxtapose between the first and second surfaces. This third surface could be curved, thereby forming a “U” shaped groove, or the third surface could be flat, thereby forming a rectangular groove. However, a “V” shaped groove generally eases manufacturing.




As shown in all Figures, bottom surface


20


also includes at least one downward projection


34


. Downward projection


34


may extend across bottom surface


20


, adjacent rear surface


16


as shown in

FIGS. 1

,


2


, and


4


. Alternatively, projection


34


may be broken into more than one projection


34


as shown in

FIGS. 6

,


7


and


9


. Projection


34


has an abutting surface


36


which is used to abut against the rear surface


16


of a lower course of blocks, thereby forming a setback between successive courses of blocks. This setback add strength and stability to the resulting wall.




Abutting surface


36


may be substantially parallel to rear surface


16


. Alternatively, for ease of manufacture, abutting surface


36


may angle rearwardly forming a relatively small angle β with rear surface


16


as shown in FIG.


3


. Angle β is preferably less than 45 degrees, more preferably less than 30 degrees. A smaller angle β provides more resistance to horizontal block slippage due to external forces against the back of the resulting wall.




The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.



Claims
  • 1. A retaining wall block for constructing a multiple course retaining wall comprising:a top surface; spaced apart front and back surfaces extending from the top surface; spaced apart side surfaces extending from the top surface and spanning from the front surface to the back surface; a bottom surface spaced apart from the top surface having a predetermined surface area and integral with the front, back and side surfaces, and having a concave portion rearwardly displaced from the front surface, the concave portion shaped to substantially form a segment of a sphere having a generally circular edge defined on said bottom surface, the concave portion creating a cavity between the bottom surface of the block and a top surface of a lower course of blocks when the block is placed on the top surface of the lower course of blocks, the cavity allowing dirt and other foreign matter to exist between successive courses of blocks without creating instability between the block and the lower course of blocks; and the top, bottom, front, back and side surfaces defining the block body, and said body being of the same, uniform material composition throughout.
  • 2. A retaining wall block for constructing a multiple course retaining wall comprising:a top surface; spaced apart front and back surfaces extending from the top surface; spaced apart side surfaces extending from the top surface and spanning from the front surface to the back surface; a bottom surface spaced apart from the top surface having a predetermined surface area and integral with the front, back and side surfaces, and having a concave portion rearwardly displaced from the front surface, the concave portion creating a cavity between the bottom surface of the block and a tot surface of a lower course of blocks when the block is placed on the ton surface of the lower course of blocks, the cavity allowing dirt and other foreign matter to exist between successive courses of blocks without creating instability between the block and the lower course of blocks; and the top, bottom, front back and side surfaces defining the block body, and said body being of the same, uniform material composition throughout; and, at least one downward projection proximate the rear surface, said downward projection having an abutting surface which contacts the rear surface of a lower course of blocks when the block is stacked thereon, thereby causing the block to be set rearwardly of the lower course of blocks.
  • 3. The block of claim 2 wherein the abutting surface of said downward projection is generally parallel to the rear surface.
  • 4. The block of claim 2 wherein the abutting surface of said downward projection forms an angle β with the rear surface which is less than 45 degrees.
  • 5. The block of claim 2 wherein the abutting surface of said downward projection forms an angle β with the rear surface which is less than 30 degrees.
  • 6. A retaining wall block for constructing a multiple course retaining wall comprising:a too surface; spaced apart front and back surfaces extending from the top surface; spaced apart side surfaces extending from the top surface and spanning from the front surface to the back surface; a bottom surface spaced apart from the top surface having a predetermined surface area integral with the front, back and side surfaces and having a concave portion rearwardly displaced from the front surface, the concave portion creating a cavity between the bottom surface of the block and a top surface of a lower course of blocks when the block is placed on the top surface of the lower course of blocks, the cavity allowing dirt and other foreign matter to exist between successive courses of blocks without creating instability between the block and the lower course of blocks; and the top, bottom, front, back and side surfaces defining the block body, and said body being of the same, uniform material composition throughout; the bottom surface further having a plurality of elongate grooves formed in the bottom surface, the elongate grooves themselves having a first surface, a second surface and a third surface, the first surface extending along the length of said groove and connecting said bottom surface with the third surface, the second surface extending along the length of said groove and connecting said bottom surface with the third surface, the third surface extending along the length of said groove, connecting the first surface with the second surface and upwardly displaced from the bottom surface.
  • 7. A block for use in constructing a retaining wall comprising:a substantially planar too surface; a bottom surface; side surfaces extending from the too surface to the bottom surface; a front surface extending vertically from the top surface to the bottom surface and extending laterally between the side surfaces; a back surface extending vertically from the too surface to the bottom surface and extending laterally between the side surfaces; the bottom surface having an upwardly recessed curved portion rearwardly displaced from the front surface that creates a vertical gap between the bottom surface and a top surface of a lower course of blocks when said block is placed thereon in the construction of the wall, the curved portion making up more than one half of the bottom surface, the bottom surface also having a planar portion substantially parallel to the top surface for providing an area for block to block contact which allows the block to sit in a stable and level position when the block is stacked on the top surface of the lower course of blocks.
  • 8. A block for use in constructing a retaining wall comprising:a substantially planar too surface; a bottom surface; side surfaces extending from the too surface to the bottom surface; a front surface extending vertically from the top surface to the bottom surface and extending laterally between the side surfaces; a back surface extending vertically from the top surface to the bottom surface and extending laterally between the side surfaces; the bottom surface having a non-planar portion, rearwardly displaced from the front surface, which creates a vertical cap between the bottom surface and a top surface of a lower course of blocks when said block is placed thereon in the construction of the wall; and, at least one elongate groove in the non-planar portion having a length, a width, and a depth, the groove extending into the block from the bottom surface upwardly toward the top surface an amount defining the depth.
US Referenced Citations (52)
Number Name Date Kind
D. 279030 Risi et al. May 1985
D. 280024 Risi et al. Aug 1985
D. 284109 Seal Jun 1986
D. 295788 Forsberg May 1988
D. 295790 Forsberg May 1988
D. 296007 Forsberg May 1988
D. 296365 Forsberg Jun 1988
D. 297464 Forsberg Aug 1988
D. 297574 Forsberg Sep 1988
D. 298463 Forsberg Nov 1988
D. 299067 Forsberg Dec 1988
D. 300253 Forsberg Mar 1989
D. 300254 Forsberg Mar 1989
D. 301064 Forsberg May 1989
D. 311444 Forsberg Oct 1990
D. 317048 Forsberg May 1991
D. 317209 Forsberg May 1991
378825 Brannigan Feb 1888
D. 380560 Forsberg Jul 1997
468838 Steiger Feb 1892
572762 Landers Dec 1896
1002161 Lambert Aug 1911
1248070 Buente Nov 1917
1727363 Bone Sep 1929
1733790 Gilman Oct 1929
2313363 Schmitt Mar 1943
2963828 Belliveau Dec 1960
3274742 Paul et al. Sep 1966
3390502 Carroll Jul 1968
3430404 Muse Mar 1969
3488964 Kubo Jan 1970
4229123 Heinzmann Oct 1980
4314431 Rabassa Feb 1982
4524551 Scheiwiller Jun 1985
4565043 Mazzarese Jan 1986
4698949 Dietrich Oct 1987
4711606 Leling et al. Dec 1987
4802320 Forsberg Feb 1989
4825619 Forsberg May 1989
4860505 Bender Aug 1989
4936712 Glickman Jun 1990
5017049 Sievert May 1991
5031376 Bender et al. Jul 1991
5044834 Janopaul Sep 1991
5062610 Woolford et al. Nov 1991
5281048 Hagenah Jan 1994
5294216 Sievert Mar 1994
5622456 Risi et al. Apr 1997
5765970 Fox Jun 1998
5820304 Sorheim et al. Oct 1998
5827015 Woolford et al. Oct 1998
5943827 Okerlund Aug 1999
Foreign Referenced Citations (23)
Number Date Country
5276586 Jan 1986 AU
8077587 Apr 1988 AU
531354 Oct 1956 CA
1040452 Oct 1978 CA
1065154 Oct 1979 CA
51160 Apr 1983 CA
51313 May 1983 CA
1 194 703 Jun 1983 CA
1 188 116 Jun 1985 CA
62875 Apr 1989 CA
63366 May 1989 CA
63365 May 1989 CA
66760 Aug 1990 CA
2012286 Sep 1991 CA
27 55 833 Jul 1978 DE
2243304 Apr 1975 EP
2343871 Oct 1977 EP
2 622 227 Apr 1989 EP
107338 Jun 1917 GB
537153 Jun 1941 GB
1386088 Mar 1975 GB
92167 Jul 1948 NZ
1145106A Mar 1985 SU
Non-Patent Literature Citations (18)
Entry
Rockwood Cottage Stone brochure, Rockwood Retaining Walls, Inc. Rochester, Minnesota USA, (no date).
Tech Spec, Diamond Wall System product literature, Sep. 1, 1988, Diamond Wall System.
Cottage Stone product literature, 1998, Rockwood Retaining Walls, Inc., Rochester, Minnesota USA.
Dura-Hold Interlocking Retaining Wall System for heavy duty protection, Risi Stone, date unknown.
Pisa II Interlocking Retaining Wall System for garden landscaping, Risi Stone, date unknown.
Blaha, Bill, Retaining Wall system Keyed to Success, date unknown, 4 pp.
Bakke, Timothy, 3 Easy Holdups, Popular Science, pp. 90-91, Jul. 1989.
Keystone Retaining Wall System, Engineers drawing, Mar. 31, 1989, 3 pp.
Keystone Garden Walls brochure, Beautiful Do-It Yourself Retaining Wall, date unknown, 2 pp.
Morrish, Claud Fancis, Exhibit CFM-4, Federal Court of Australia Queensland District Registry General Division, Oct. 8, 1996, 2 pp.
Keystone International memorandum, Mar. 21, 1989, David Bear to Tim Bakke.
Author unknown, Profile Hex Masonry Units PHX-1, date unknown, 1 pp.
New Holland Concrete product literature, Dream the Possibilities, Martin Limestone, Inc. New Holland, PA, USA, (date unknown).
Castle Wall brochure, National Concrete Masonry Association, USA, 1996.
Decor Innovating Concrete Systems product information sheet, Decor Easi Wall, Ontario CA, date unknown, 1 pp.
Keystone Retaining Wall Systems, Garden Wall brochure, 1991.
Tech Spec, Aztech Wall System product literature, Anchor Block Company, Sep., 1988, Diamond Wall System.
Besser Parts & Equipment, Besser Company, Alpena, Michigan, date unknown.