U.S. patent application number 11/978381 was filed with the patent office on 2008-03-13 for invertible retaining wall block.
This patent application is currently assigned to Mortarless Technologies LLC. Invention is credited to Brian A. Price, Gerald P. Price, Raymond R. Price.
Application Number | 20080063480 11/978381 |
Document ID | / |
Family ID | 38581421 |
Filed Date | 2008-03-13 |
United States Patent
Application |
20080063480 |
Kind Code |
A1 |
Price; Brian A. ; et
al. |
March 13, 2008 |
Invertible retaining wall block
Abstract
An invertible retaining wall block comprises a front portion, a
rear portion and a neck portion connecting the front portion and
rear portion. A projection extends outwardly from the block to
interlock with similar blocks in adjacent courses of blocks. One or
more notches are provided to the front portion in order to allow
the base course of blocks to be placed in an inverted orientation
with respect to subsequent courses because the notch provides
clearance for the protrusion.
Inventors: |
Price; Brian A.; (Rochester,
MN) ; Price; Raymond R.; (Rochester, MN) ;
Price; Gerald P.; (Rochester, MN) |
Correspondence
Address: |
Patterson, Thuente, Skaar & Christensen, P.A.
4800 IDS Center
80 South 8th Street
Minneapolis
MN
55402-2100
US
|
Assignee: |
Mortarless Technologies LLC
|
Family ID: |
38581421 |
Appl. No.: |
11/978381 |
Filed: |
October 29, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11400923 |
Apr 10, 2006 |
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11978381 |
Oct 29, 2007 |
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29240236 |
Oct 11, 2005 |
D547881 |
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11400923 |
Apr 10, 2006 |
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29240237 |
Oct 11, 2005 |
D548365 |
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11400923 |
Apr 10, 2006 |
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29240278 |
Oct 11, 2005 |
D546972 |
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11400923 |
Apr 10, 2006 |
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29240296 |
Oct 11, 2005 |
D555808 |
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11400923 |
Apr 10, 2006 |
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Current U.S.
Class: |
405/286 |
Current CPC
Class: |
E04C 1/395 20130101;
E02D 29/025 20130101; E04B 2002/0215 20130101; E02D 29/0266
20130101 |
Class at
Publication: |
405/286 |
International
Class: |
E02D 5/12 20060101
E02D005/12 |
Claims
1. A method of building a retaining wall, comprising: forming a
base course by placing a first plurality of blocks of a first block
shape onto a base surface in a first orientation; forming a second
course adjacent to the base course by placing a second plurality of
blocks of the first block shape on top of the base course in a
second orientation, the second orientation being vertically
inverted with respect to the first orientation; interlocking the
second course with the first course by disposing a protrusion
extending from each of the second plurality of blocks in a notched
portion defined in the first plurality of blocks.
2. The method of claim 1, further comprising interlocking the
second course with the first course by disposing a protrusion
extending from each of the first plurality of blocks in a notched
portion defined in the first plurality of blocks.
3. The method of claim 1, further comprising forming a third course
adjacent to the second course by placing a third plurality of
blocks of the first block shape on top of the second course in the
second orientation.
4. The method of claim 3, further comprising interlocking the third
course with the second course by disposing a protrusion extending
from each of the third plurality of blocks in an opening defined by
front, neck and rear portions of the second plurality of
blocks.
5. The method of claim 3, further comprising disposing a portion of
an earth anchor between two of the courses of blocks that form the
wall.
6. The method of claim 2, further comprising forming a top course
by disposing a cap block on top of an adjacent course of
blocks.
7. The method of claim 1, further comprising forming a third course
adjacent to the second course by placing a third plurality of
blocks of a second block shape on top of the second course.
8. A method of building a retaining wall, comprising: forming a
plurality of retaining wall blocks, each block comprising a front
portion and a rear portion connected by a neck, the neck extending
from a rear side of the front portion defining a pair of rearwardly
facing surfaces on the front portion, the block presenting a top
surface and a bottom surface, the front portion defining a notch in
each of the pair of rearwardly facing surfaces, each notch
extending from the bottom surface and presenting a depth dimension
relative to the bottom surface, the block further including a
projection extending outwardly from the bottom surface, the
projection presenting a height dimension relative to the bottom
surface, wherein the depth dimension of each notch is greater than
or equal to the height dimension of the projection; forming a base
course wherein the projection of each of the retaining wall blocks
faces upward; forming a second course adjacent to the base course
wherein the projection of each of the retaining wall blocks faces
downward and the projections interlock with respective notches of
the blocks in the base course.
9. The method of claim 8, further comprising forming a further
course wherein the projection of each of the retaining wall blocks
faces downward.
10. A method of building a retaining wall, comprising: forming a
plurality of retaining wall blocks, each block comprising a front
portion and a rear portion, the rear portion being narrower than
the front portion, a neck portion connecting the front portion and
rear portion, the neck portion being narrower than the rear
portion, first and second notches defined inwards in the front
portion, each notch extending from a bottom surface of the block
and presenting a depth dimension relative to the bottom surface and
a width dimension extending laterally along the front portion
towards the neck portion, wherein the width dimension is greater
than the depth dimension, and a projection extending outwardly from
the bottom surface of the block and located between the first and
second notches.; forming a base course of blocks on a base surface
with the projection of each block facing upward; forming a second
course on top of the base course with the projection of each of the
blocks facing downward and the projections interlocking with
respective notches of the blocks in the base course.
11. The method of claim 10, wherein the second course is shifted
horizontally by one-half of a block relative to the base
course.
12. The method of claim 11, wherein the second course includes a
half block.
13. The method of claim 10, further comprising forming a third
course on top of the second course wherein the projection of each
of the blocks faces downward.
14. The method of claim 10, further comprising depositing fill
material into openings defined by the front, neck and rear portions
of the blocks
15. The method of claim 10, further comprising disposing a portion
of an earth anchor between the base course and the second
course.
16. The method of claim 10, further comprising forming a top course
by disposing a cap block on top of an adjacent course of blocks.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
11/400,923 filed Apr. 10, 2006, which in turn is a
continuation-in-part of U.S. Design patent application Ser. No.
29/240,236, filed Oct. 11, 2005, now U.S. Design Pat. No. D547,881,
U.S. Design patent application Ser. No. 29/240,237, filed Oct. 11,
2005, now U.S. Design Pat. No. D548,365, U.S. Design patent
application Ser. No. 29/240,278, filed Oct. 11, 2005, now U.S.
Design Pat. No. D546,972 and U.S. Design patent application Ser.
No. 29/240,296, filed Oct. 11, 2005, all of which are hereby fully
incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to stackable
concrete blocks and more particularly to concrete blocks which may
be stacked with a base course in an inverted configuration.
BACKGROUND OF THE INVENTION
[0003] Concrete blocks for free standing and retaining walls have
been known and used for many years. They can be both functional and
decorative, and range from small gardening applications to
large-scale construction projects. Such walls are typically used to
form horizontal surfaces or terraces by providing a generally
vertical barrier behind which backfill may be deposited. Such walls
reduce erosion and slumping and maximize land use.
[0004] Walls can be constructed from stackable concrete blocks.
Blocks are stacked in horizontal rows called courses. Multiple
successive courses may be used to create a vertically rising wall
of a desired height. These types of blocks can generally be
assembled quickly and economically due to the interlocking of
adjacent courses of blocks. Typically, each block includes some
type of interlocking system such as pins, lips or projections so
that one course of blocks interlocks with an adjacent course of
blocks to create a stable structure. These features are often
located on the bottom surfaces of the blocks and project downward
into an opening in a lower course of blocks because if the
projections are on the top surface of the blocks the wall will
require specially manufactured cap blocks. This, however, can cause
problems with the first course of blocks because it is laid
directly upon the base surface so there is no open area for the
interlocking features to rest in. In order to create a level base
course, builders often have to excavate material from the base
surface. This process often makes the base course the most
difficult and time consuming course to build. Alternatively, blocks
manufactured without projections can be used in the base course.
This, however, requires having two different types of blocks on
hand which increases the cost and complexity of stacking,
manufacturing, storing, and palletizing the blocks.
SUMMARY OF THE INVENTION
[0005] The present invention addresses the need to provide for a
block design that can form a base and subsequent courses without
the need for separate base blocks or provision of relief in the
base surface. Such invertible retaining wall block comprises a
front portion, a rear portion and a neck portion connecting the
front portion and rear portion. A projection extends outwardly from
the block to interlock with similar blocks in adjacent courses of
blocks. One or more notches are provided to the front portion in
order to allow the base course of blocks to be placed in an
inverted orientation with respect to subsequent courses because the
notch provides clearance for the protrusion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view showing the bottom of an
invertible retaining wall block according to an embodiment of the
present invention.
[0007] FIG. 2 is a bottom view of an invertible retaining wall
block according to an embodiment of the present invention.
[0008] FIG. 3 is a top view of an invertible retaining wall block
according to an embodiment of the present invention.
[0009] FIG. 4 is a side view of an invertible retaining wall block
according to an embodiment of the present invention.
[0010] FIG. 5 is a perspective view of a plurality of invertible
retaining wall blocks stacked in a wall segment according to an
embodiment of the present invention.
[0011] FIG. 6 is a side view of a plurality of invertible retaining
wall blocks showing a stacking arrangement according to an
embodiment of the present invention.
[0012] FIG. 7 is a side view of a plurality of invertible retaining
wall blocks in stacked configuration in combination with an earth
anchor according to an embodiment of the present invention.
[0013] FIG. 8A is a bottom perspective view,
[0014] FIG. 8B is a side view,
[0015] FIG. 8C is a bottom view, and
[0016] FIG. 8D is a rear view of an invertible retaining wall block
according to an embodiment of the present invention.
[0017] FIG. 9A is a bottom perspective view,
[0018] FIG. 9B is a side view,
[0019] FIG. 9C is a bottom view, and
[0020] FIG. 9D is a rear view of a retaining wall block according
to an embodiment of the present invention.
[0021] FIG. 10A is a bottom perspective view,
[0022] FIG. 10B is a side view,
[0023] FIG. 10C is a bottom view, and
[0024] FIG. 10D is a rear view of a retaining wall block according
to an embodiment of the present invention.
[0025] FIG. 11A is a bottom perspective view,
[0026] FIG. 11B is a side view,
[0027] FIG. 11C is a bottom view, and
[0028] FIG. 11D is a rear view of a retaining wall block according
to an embodiment of the present invention.
[0029] FIG. 12A is a bottom perspective view,
[0030] FIG. 12B is a side view,
[0031] FIG. 12C is a bottom view, and
[0032] FIG. 12D is a rear view of a retaining wall block according
to an embodiment of the present invention.
[0033] FIG. 13 is a perspective view of an invertible retaining
wall block according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0034] Referring to FIGS. 1-4 there can be seen an invertible
retaining wall block 100 according to an embodiment of the present
invention. Invertible block 100 generally comprises a head or front
portion 102 and a tail or rear portion 104 connected by a
transverse or neck portion 106.
[0035] Front portion 102 comprises a front surface 108 and opposing
rearwardly facing or rear-facing inner surface 110 on the rear side
111 of the front portion 102, a top surface 112 and opposing bottom
surface 114 and opposing first 116 and second 118 side surfaces.
Rear portion 104 comprises a rear surface 120 and opposing
forward-facing inner surface 122, a top surface and 124 and
opposing bottom 126 surface, and opposing first 125 and second 127
side surfaces. The neck portion 106 extends between the inner
surfaces 110 and 122 of front portion 102 and rear portion 104 and
includes a top surface 134 and opposing bottom surface 154 and
first 138 and second 140 side surfaces. As shown in FIG. 13, neck
portion 106 may optionally be provided with a slot 136 in which
horizontal reinforcement may be placed, as is known in the art. The
top surfaces 112, 124, and 134 of the front portion 102, rear
portion 104, and neck portion 106 define a block top surface 142.
The bottom surfaces of 114, 126, 154 of front portion, rear
portion, and neck portion define a block bottom surface 144.
[0036] Front surface 108 of front portion 102 may be given a
decorative appearance. Such decorative appearances include broken
rock, stacked rocks, natural stone, brick, striated or roughened
texture. Persons of skill in the art will recognize that the
present invention is not limited to a specific decorative facial
appearance unless specifically indicated in a given Claim.
Alternatively, some or all of front surface 108 may be provided
with a smooth appearance.
[0037] Invertible block 100 further includes a projection 121
extending outwardly from the block opposite of block top surface
142. Projection 121 comprises an interlocking portion 128 and a
spacing portion 130. Interlocking portion 128 includes a front
surface 146 and opposing rear surface 148, opposing first 150 and
second 152 side surfaces, and an indexing surface 154. Indexing
surface 154 may comprise some or all of the same surface as neck
portion bottom surface. Side surfaces 150, 152 extend only partway
along the length of top surface, until intersecting with side
surfaces 138, 140 of neck portion. Front surface 146 of
interlocking portion 128 is generally perpendicular in order to
facilitate the interlocking of adjacent blocks. Rear surface 148
and side surfaces 150, 152 may be at an angle to make projection
121 easier to manufacture. Interlocking portion 128 may be
generally rectangular, square, triangular, trapezoidal, or any
other similar shape.
[0038] Spacing portion 130 extends outwardly from rear surface 148
of interlocking portion 128 and outwardly opposite of block top
surface 142. Spacing portion 130 comprises a tail portion 129 and a
tapered neck portion 131. A projection 121 formed of an integral
interlocking portion 128 and spacing portion 130 increases the
strength and chipping resistance of the projection 121. Although
one specific spacing portion 130 configuration is depicted, one of
skill in the art will recognize that spacing portion 130 may take
on a variety of configurations, for example, neck portion 131 may
not taper, linearly taper, taper in the opposite direction, or be
eliminated. Spacing projection 130 has dual functions, one of which
is to position the block when it is placed on a lower course of
blocks that are arranged in a convex course, the other of which is
to facilitate stacking on a pallet for shipping.
[0039] Invertible block 100 also includes first and second notched
portions 132, 133 defined in front portion 102. Notched portions
132, 133 each include a stop surface 135 and extend inward from
front portion inner surface 110 and downward from front portion
bottom surface 114. Notched portions 132, 133 are located on each
side of neck portion 106 and may extend laterally from front
portion side surfaces 116 and 118 to interlocking portion side
surfaces 150 and 152. The depth of notched portions 135 from bottom
surface 114 of front portion 102 is preferably greater than, but at
least equal to, the distance that interlocking portion 128 extends
outward opposite of block top surface 142. Notched portions 132,
133 may define a curve, a right angle, or any other angle. As will
be described more fully below, notched portions 132 allow
invertible blocks 100 to be stacked with an inverted base
course.
[0040] Referring now to FIGS. 5 and 6, there can be seen a
plurality of invertible blocks 100 according to an embodiment of
the present invention in a stacked configuration. Blocks in each
course are laid such that the side surfaces 116 and 118 of the
front portion 102 of each block 100 abut a side surface of the
front portion of each adjacent block. When a course has been laid,
fill material, such as rock or dirt, may be backfilled behind the
blocks and into the space between the inner surfaces 110 and 122 of
the front portion 102 and rear portion 104 to help stabilize the
wall.
[0041] Blocks 100a in the base course 156 are laid upside down,
with the top surface 142a of each base block 100a contacting the
ground or other base surface. Consequently, the interlocking
portion 128a and spacing portion 130a of each projection 129a of
each base block 100a extend upwardly from each block 100a. It is
therefore unnecessary to dig a recess in the base surface to create
a level base course.
[0042] The second course 158 of blocks 100b is then placed on top
of the first course 156 in the usual orientation, with the bottom
surface 144 of the blocks facing downward. Each block 100b in the
second course is centered above two base blocks 100a. Stop surfaces
135b of notched portions 132b, 133b of the blocks 100b in the
second course 158 may rest upon the indexing surfaces 154a of
interlocking portions 128a of projections 129a of base blocks 100a.
In addition, indexing surfaces of interlocking portions of the
blocks in the second course may rest upon stop surfaces of notched
portions in base blocks. Because the depth of notched portions is
greater than or equal to the height of interlocking portions,
bottom surfaces of front and rear portions of the second course 158
rest flush against bottom surfaces of front and rear portions of
first course 156. Spacing portions 130b in the second course 158 of
blocks rest between rear portion side surfaces 125a and 127a of
each pair of base blocks 100a.
[0043] When two courses of blocks are inverted and placed on each
other, the outermost sections of the front portion 102b of each
block 100b in the second course 158 are aligned with the
interlocking portions 128a projecting outward from the top surface
102a of the blocks 100a in the first course 156, which would
ordinarily cause the second course 158 to rest unevenly on the
first course 156. However, the addition of notched portions 132b,
133b greater than or equal to the height of the interlocking
portions 128a to receive the interlocking portions 128a allows the
second course to rest flush on the first course. Notched portions
in base blocks that are aligned with the portion of interlocking
portions of the blocks in the second course that would otherwise
rest upon bottom surface of base block front portions further
prevent blocks from resting unevenly on each other. Blocks of this
design therefore allow the base course 156 to be placed upside
down, with the projections 129a projecting upwardly, which
eliminates the need either to dig up a portion of the base surface
to accommodate projections or to use a projectionless base course
of blocks.
[0044] The third course 160 of blocks 100c, and subsequent courses,
can then be added in the same orientation as the second course 158.
Projections 129c of the blocks 100c in the third course 160 rest
against the front portion inner surfaces 110b of the second course
of blocks. This prevents forward movement of each new course of
blocks and also creates a setback between adjacent courses.
[0045] In order for blocks to align properly such that a block in
an overlying course rests between two blocks in an underlying
course, block courses must be shifted by half of a block relative
to one another. This is commonly referred to as a running bond.
Accordingly, half-blocks having a notched portion can be utilized
to provide this offset and, where necessary, to present a finished
appearance to ends of walls where necessary. Such half-blocks as
well as quarter-blocks, corner blocks, cap blocks and other block
variations can be provided by slight variations to the basic block
design, as is known in the art. Due to the generally planar nature
of top surface of invertible blocks, conventional cap blocks having
a flat bottom surface can be used.
[0046] Because rear portion 104 is narrower in width that front
portion 102, blocks may be oriented at oblique angles to one
another to create curved or serpentine walls. Due to this size
difference, rear portions 104 of adjacent angled blocks do not
interfere with one another even when blocks are angled towards one
another.
[0047] A wall 163 formed of invertible blocks 100A-100E is shown in
FIG. 7. Note that for simplicity of presentation, the detailed
features 100A-100E of these blocks are not shown. Wall 163 may
include a course of cap blocks 165 as the top course of the wall
163 to provide a finished appearance to the top of the wall. Wall
163 may also utilize an earth anchor 162. The present invention may
be used with various types of earth anchors 162, such as such as
metal grids or lattices and plastic grids or lattices such as
geo-grid, which are known in the art and significantly improves the
stability of a wall. An earth anchor 162 may be placed between
courses of blocks 100 and extends back into the material behind the
wall. Earth anchor 162 is held in place by the weight of the blocks
and fill material, as is known in the art.
[0048] Blocks of the present invention are preferably made from a
rugged, weather resistant material, such as zero-slump concrete,
for high strength and durability in outdoor applications. However,
blocks may be made of numerous other materials, for example,
plastic, fiberglass, wood, metal, or stone. Blocks are most
preferably manufactured in a high-speed application using the so
called dry-cast manufacturing method known in the art. The material
composition for such process generally comprises sand, aggregate,
cement, fly ash and, optionally, selected admixtures. Persons
having skill in the art of dry-cast concrete block manufacture
understand that material mixtures can be varied to meet a variety
of performance requirements.
[0049] Persons of skill in the art will recognize that by providing
a block design that can be manufactured with at least one of a flat
top or bottom surface, the manufacturing process can be performed
more easily, quickly and inexpensively using dry-cast manufacturing
methods, when compared to designs that do not have at least one of
a flat top or bottom surface. These advantages are due, at least in
part, to the fact that core pulling need not be performed to form
relief in the block surface opposite the compression head.
[0050] Referring now to FIGS. 8A-8D, there can be seen an
invertible block 200 according to another embodiment of the present
invention. Invertible block 200 comprises a front portion 202 and a
rear portion 204 connected by a neck portion 206 with an
interlocking projection 228 extending from a bottom surface 244 of
the block 200. FIGS. 8A-8D depict an alternative straight-faced,
planar, front surface 208 of front portion 202, as opposed to the
multi-faceted, beveled front surface 108 of invertible block 100.
In addition, notched portions 232, 233 of invertible block 200
extend only partway from front portion side surfaces 216 and 218
towards interlocking projection 228. Courses of blocks having such
notched portions 232, 233 can still be stacked in an inverted
fashion because, as can be seen in FIG. 5, interlocking portions in
the first course interfere with only the outermost sections of
front portion of the second course. Notched portions, therefore,
need only be large enough to accommodate the interfered with
portion and need not span the entirety of the top surface of front
portion. In addition, invertible block 200 includes a spacing
projection 230 that is separate from interlocking projection 228.
This makes invertible block 200 lighter and easier to handle than
invertible block 100. Separate spacing projection 230 will also
still serve its dual functions of positioning blocks when placed on
a lower course of blocks that are arranged in a convex course and
facilitating stacking on a pallet for shipping.
[0051] FIGS. 9A-9B depict a retaining wall block 300 according to
another embodiment of the present invention. Block 300 comprises a
front portion 302 and a rear portion 304 connected by a neck
portion 306. Block 300 includes an interlocking projection 328 and
a spacing projection 330 extending outwardly from a bottom surface
344 of block 300. Interlocking projection 328 and spacing
projection 330 serve to interlock adjacent courses of blocks. Block
300 further includes a recessed portion 364 adjacent interlocking
projection 328. Recessed portion 364, along with a smaller
interlocking projection 328 and spacing projection 330, decreases
the weight of the block 300 which makes blocks easier to transport
and manipulate. Recessed portion 364 also provides additional
clearance between courses of blocks. Further, recessed portion 364
allows blocks 300 to be stacked in either a columnar or running
bond fashion.
[0052] A retaining wall block 400 according to another embodiment
of the present invention is shown in FIGS. 10A-10D. Block 400
comprises a front portion 402 and a rear portion 404 connected by a
neck portion 406. Block 400 includes a projection 428 extending
outwardly from a bottom surface 444 of the block 400. This single
projection 428 serves the functions provided by both the
interlocking projection and the spacing projection of the above
described blocks. Unitary projection 428 also provides a stronger
and more chip resistant projection. In addition, block 400 is
provided with a splitting groove 467 located along the length of
projection 428. Splitting groove 467 allows for blocks to be more
easily split in half to form half blocks, the use of which is
described above.
[0053] Referring now to FIGS. 11A-11D, there can be seen another
retaining wall block 500 according to an embodiment of the present
invention. Block 500 comprises a front portion 502 and a rear
portion 504 connected by a neck portion 506. Block 500 includes an
interlocking projection 528 and a spacing projection 530 extending
outwardly from a bottom surface 544 of the block 500. Interlocking
projection 528 and spacing projection 530 serve to interlock
adjacent courses of blocks and spacing projection 530 further
serves to facilitate palletizing. Interlocking projection 528 uses
less material than, for example, interlocking projections 128 and
228, and therefore makes block 500 easier to transport and
manipulate. Interlocking projection 528 is also easy to manufacture
because a majority of its perimeter is angled. In addition, the
angled sides of interlocking projection 528 permit tighter radius
curves when walls are constructed from blocks 500 with the tail
portions 504 removed.
[0054] FIGS. 12A-12D depict a retaining wall block 600 according to
another embodiment of the present invention. Block 600 comprises a
front portion 602 and a rear portion 606 connected by a neck
portion 604. An interlocking projection 628 and a spacing
projection 630 similar to interlocking projection 528 and spacing
projection 530 extend outwardly from a bottom surface 644 of the
block 600. Block 600 further includes a core 668 through rear
portion 606 which decreases the weight of the block and can be
filled with a fill material to strengthen a wall of such blocks as
is known in the art. Further, ears 670, 672 projecting outwardly
from rear portion allow a wall of such blocks to have a
substantially closed rear surface so that fill material contained
therein cannot move outwardly. Block 600 is also a larger and
longer block than the previously disclosed embodiments, which
allows for higher walls to be more easily constructed in demanding
situations.
[0055] The present invention has been described with reference to
preferred embodiments. However, particular features of each of the
exemplary embodiments may be mixed and matched with the features of
any other embodiment, depending on the demands of the particular
situation in which the block is to be used, without departing from
the spirit and scope of the invention.
* * * * *