U.S. patent application number 09/928125 was filed with the patent office on 2002-03-07 for interlocking masonry wall block.
This patent application is currently assigned to Bend Industries, Inc.. Invention is credited to Whitson, Robert L..
Application Number | 20020028114 09/928125 |
Document ID | / |
Family ID | 22840840 |
Filed Date | 2002-03-07 |
United States Patent
Application |
20020028114 |
Kind Code |
A1 |
Whitson, Robert L. |
March 7, 2002 |
Interlocking masonry wall block
Abstract
The present invention relates to an interlocking masonry wall
block having an open core and spaced projections that enable
stacked blocks to be interlocked, setback and staggered to form a
stable gravity-type retaining wall that is particularly suited for
landscaping applications. The open core extends completely through
the block from top to bottom. The block is formed by front, rear
and opposed side walls, each having parallel inside and outside
surfaces. One projection extends from the lower surface of each
side wall. The front of each projection is forward the inside
surface of the front wall to provide the setback when stacked on
other like-shaped blocks. Each block is stacked in a staggered
manner atop two other blocks. One projection of each block is
received by the open core of one of the two lower blocks. The
projections abut the inside surface of the front wall of the lower
blocks to interlock the blocks together. The block has a preferably
trapezoidal shape with a wider front wall to help accommodate the
formation of serpentine walls. The block can be used to make
serpentine walls with straight and curved portions with a
relatively constant pitch.
Inventors: |
Whitson, Robert L.; (West
Bend, WI) |
Correspondence
Address: |
Jeffrey S. Sokol
Sokol Law Office
828 North Broadway, Suite 850
Milwaukee
WI
53202
US
|
Assignee: |
Bend Industries, Inc.
|
Family ID: |
22840840 |
Appl. No.: |
09/928125 |
Filed: |
August 10, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60224471 |
Aug 10, 2000 |
|
|
|
Current U.S.
Class: |
405/284 ;
52/609 |
Current CPC
Class: |
E02D 29/025 20130101;
E04B 2002/0223 20130101; E04C 1/395 20130101 |
Class at
Publication: |
405/284 ;
52/609 |
International
Class: |
E04B 005/04 |
Claims
I claim:
1. A masonry wall block for stacking atop other like-shaped blocks,
the masonry wall block comprising: a main body having a front wall,
a rear wall and first and second side walls, each of said walls
having inside and outside surfaces and upper and lower surfaces,
said inside surfaces of said walls forming an open core, said upper
surfaces of said walls forming an upper surface of said main body,
and said lower surfaces of said walls forming a lower surface of
said main body, said upper and lower surfaces of said main body
being substantially parallel; first and second spaced apart,
projections extending from said lower surface of said main body,
said first projection extending from said lower surface of said
first side wall and said second projection extending from said
lower surface of said second side wall, each of said projections
being located on opposite sides of said open core, and each of said
projections having a portion with a front surface located between
said inside and outside surfaces of said front wall to define a
setback dimension; and, wherein said block is adapted to be stacked
in a staggered relationship atop first and second lower like-shaped
blocks, said first projection of said block being received by said
open core of said first lower like-shaped block, and said second
projection of said block being received by said open core of said
second lower like-shaped block, said front surface of each of said
projections of said block being adapted to abuttingly engage said
inside surface of said front wall of its respective lower
like-shaped block, and said block being positioned rearwardly of
said lower like-shaped blocks an amount equal to said setback
dimension when in said abutting engagement with said lower
like-shaped blocks.
2. The masonry wall block of claim 1, and wherein each of said
projections has a second portion with a rear surface located
between said inner surfaces of said front and rear walls, each of
said projections having a thickness dimension greater then its said
setback dimension.
3. The masonry wall block of claim 2 and wherein said setback
dimension is less than half said thickness dimension.
4. The masonry wall block of claim 1 and wherein said abutting
engagement forms an interlock between said block and the first and
second lower like-shape block, said interlock preventing said block
from being pushed forward relative to said lower like-shaped
blocks.
5. The masonry wall block of claim 1, and wherein said block has a
predetermined width dimension between said outside surfaces of said
first and second side walls, said open core has a predetermined
width dimension between said inside surfaces of said first and
second side walls, and each of said projections has opposed side
surfaces and a predetermined width dimension between said opposed
side surfaces, and wherein said width dimension of each of said
projections is less than one tenth of said width dimension of said
block, and said width dimension of said open core is at least half
said width dimension of said block, and wherein said block is able
to be staggered various amounts atop said lower like-shaped
blocks.
6. The masonry wall block of claim 5 and wherein said width
dimension of each of said projections is about one seventh that of
said width dimension of said open core.
7. The masonry wall block of claim 5 and wherein said like-shaped
blocks are adapted to be offset to form a gap between said side
walls of said like-shaped blocks.
8. The masonry wall block of claim 1, and wherein said inside and
outside surfaces of said front, rear and opposed side walls are
substantially perpendicular to said upper and lower surfaces.
9. The masonry wall block of claim 8, and wherein said inside and
outside surfaces of said front wall are substantially parallel,
said inside and outside surfaces of said rear wall are sustantially
parallel, said inside and outside surfaces of said first side wall
are substantially parallel, and said inside and outside surfaces of
said second side wall are substantially parallel.
10. The masonry wall block of claim 9, and wherein said front
surface of each of said projections is substantially parallel to
said inner surface of said front wall.
11. The masonry wall block of claim 1, and wherein said block is
adapted for use with a plurality of other like-shaped blocks to
form a multi-course wall having a serpentine shape with gradually
increasing curved portions.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates to a masonry block for stacking on
other like-shaped blocks in a staggered, interlocking and offset
manner to form a gravity-type retaining wall that is particularly
suited for integrating into a variety of landscape settings.
BACKGROUND OF THE INVENTION
[0002] A variety of masonry block designs have been developed for
building gravity-type retaining walls that depend on the weight of
the blocks for their stability. Versatile block designs should take
several factors into consideration. For walls three feet in height
or less, the blocks should form a wall structure that can withstand
the pressure of the earth behind the wall. The footprint of the
block should be large enough to accommodate soils with relatively
low bearing pressures so that the wall will not tilt or sink during
use. The setback and height of the block should be such that the
combined pressure of the earth and the weight of the wall fall
within the footprint of the lowest course of blocks. The block
design should also take into account the shape of the blocks, as
well as the strength, density and durability of the material
forming the block.
[0003] Retaining wall block designs require a mechanism for
securing the blocks together to produce a stable wall structure.
While the friction between the relatively rough surfaces of stacked
blocks can help keep the wall together, this friction is not
sufficient in many retaining wall applications. To increase
stability, some blocks are designed to be mortared or otherwise
adhered together to produce a rigid wall structure. Unfortunately,
such retaining walls are prone to cracking due to settling, frost,
water buildup behind the wall and earthquakes, as well as the
normal use of the wall by people and animals that walk, stand, lean
or sit on the wall.
[0004] Other retaining wall block designs incorporate fasteners
such as rods, pins or keys to hold and clamp the blocks together.
Examples of such block designs are shown in U.S. Pat. Nos.
4,914,876 to Forsberg, 3,390,502 to Carroll, and 4,909,010 to
Gravier, the disclosures of which are incorporated by reference
herein. A significant problem with these block designs is the
expense of the extra components and increased installation costs.
These designs can also suffer from unsightly cracks that tend to
form in these types of walls.
[0005] Interlocking wall block designs have been developed to
overcome the problems associated with the blocks that form rigid
retaining wall structures. Interlocking block designs typically
have one or more integral projections extending from the upper or
lower surface of the block. When stacked, the projection of one
block abuts against a surface of another block to help hold the
blocks together. The projections also provide a mechanism for
offsetting stacked blocks. This offset or setback helps produce a
more stable retaining wall that leans into the earth or hill behind
the wall to resist the pressure exerted by the earth or hill on the
wall. Individual blocks do not need to be rigidly secured by
mortar, adhesive, rods, pins or keys, so that the wall is free to
flex and accommodate movements in the wall caused by settling,
frost, water buildup, earthquakes and normal use. Blocks for
retaining walls of this type are described in U.S. Pat. Nos.
5,827,015 to Woolford, 2,313,363 to Schmitt, and 4,565,043 to
Mazzarese, the disclosures of which are incorporated by reference
herein.
[0006] One problem with conventional interlocking masonry wall
blocks is that the thickness of the integral projection is directly
related to the amount of setback desired for each course of blocks.
A retaining wall application requiring a half-inch setback per
course requires blocks with half-inch thick projections. Yet, thin
projections are structurally weak and prone to chipping and
cracking. While the height of the block can be increased to
increase the thickness of its setback, this results in a heavier
block that is more difficult to handle. In addition, tall blocks
also do not lend themselves to landscaping gradually sloping
terrain. Large portions of the block stick out above ground level
before a step down at the end of a row or course of blocks can
occur. This produces an unsightly wall and results in a waste of
material.
[0007] Another problem with conventional interlocking masonry wall
blocks is that the integral projection is located along the rear or
front edge of the block. As noted above, the setback projection is
frequently only a half-inch thick when the blocks are sized for
easy handling. Yet, these relatively thin and weak projections are
located where they are easily damaged if dropped, improperly
stacked or otherwise mishandled. In addition, rear projections are
in direct contact with the wetness and acidity of the earth during
use, which can cause the projection to deteriorate, weaken and fail
over time. Front projections extend upwardly and can collect water
between them and the upper course of blocks, which can freeze and
crack the projection.
[0008] A further problem with conventional interlocking masonry
wall blocks is that the integral projections are relatively short
in height to reduce the possibility of chipping and cracking.
Although the short projections may be less likely to crack, they do
not provide a sufficiently tall abutment to easily and consistently
align the block over a lower course of blocks. During construction
of a wall, workers have a tendency to leave a gap between the
projection and the lower course of blocks or allow the projection
to ride-up onto the upper surface of the lower block. These
misalignments are not easily detected given the thinness of the
projection and its relatively small height. This is especially so
for blocks with rear projections that extend down from the lower
surface of the block, because the workers are not able to easily
see that the blocks are properly aligned. Misalignments can be even
more difficult to notice in construction settings where dirt,
gravel and other debris are present, and may compact against the
setback projection or get on the upper or lower surfaces of the
blocks.
[0009] A still further problem with conventional interlocking
masonry wall blocks is that they have limited ability to produce
serpentine walls with straight, concave and convex portions. The
integral projections are sized and shaped to fit into grooves of
lower blocks so that the stacked blocks must be oriented a
particular way. If a curve is possible, the radius of the curve is
constant, so that a true serpentine wall with curves that gradually
increase or decrease in radius are not possible. These limitations
of conventional block designs prevent the wall from being
integrated into the natural contours of the landscape and thus
impede the aesthetic value of the wall.
[0010] A still further problem with conventional interlocking
masonry wall blocks is that the integral projections do not ensure
an even amount of setback for straight and curved portions of the
wall. For example, a block with a flange along its front or rear
edge produces a wall with discontinuities in the amount of setback
between adjacent block as shown in FIG. 14. In addition, the pitch
of the wall is also greater in both the concave and convex curved
portions of the wall than in the straight portions as shown in
FIGS. 14 and 16. This increasing setback and pitch occurs even
though a retaining wall may need to be stronger and require more
setback in straight portions of the wall than in curved
portions.
[0011] A still further problem with conventional interlocking
masonry wall blocks is that the blocks require a fixed amount of
lateral offset to the right or left of the lower blocks on which
they rest. Yet, obstructions at the location where the wall is to
be built or the addition of drain pipes in the wall do not always
permit each block to be offset a constant amount throughout the
entire wall. A block in one course may need to be laterally offset
two or three inches to the right or left from the blocks beneath
it, and another block in the same or a different course may need to
be laterally offset four or five inches from the blocks beneath it.
Yet, many interlocking block designs do not allow sufficient
flexibility to offset the blocks as needed to accommodate various
obstacles or drain pipes. This inflexibility can complicate
construction or renders the block unusable for some retaining wall
applications.
[0012] A still further problem with conventional interlocking
masonry wall blocks is that the integral projection does not
provide sufficient resistance to lateral side-to-side movement of
the block. Side-to-side movement is only resisted by adjacent
blocks in the same course or tier. The side walls of these adjacent
blocks abut each other to prevent side-to-side movement. However,
should one block in a given course shift or move out of abutting
alignment with one of its adjacent blocks, then each of the blocks
in that row would be susceptible to shifting as well. Moreover, the
blocks that form an end of the wall are not restrained from lateral
movement away from its sole adjacent block and could be knocked off
the wall altogether.
[0013] A still further problem with conventional interlocking
masonry wall blocks is that several different block shapes must be
combined to form the straight and curved sections of a serpentine
wall. The need for multiple block designs result in increased
manufacturing, inventory, shipping and construction costs. The
multiple block designs also result in more complicated serpentine
wall designs that are not easily integrated to the shape of a
specific and unique landscape setting.
[0014] A still further problem with conventional interlocking
masonry wall blocks is that they are heavy and difficult to handle.
The blocks are typically solid throughout. The openings tend to be
small and do not significantly reduce the weight of the block. The
excessive weight is compounded by the fact that the block must be
tall enough to provide a setback projection or flange that is
sufficiently thick to withstand cracking and chipping during
transport, construction and use.
[0015] The present invention is intended to solve these and other
problems.
BRIEF DESCRIPTION OF THE INVENTION
[0016] The present invention relates to an interlocking masonry
wall block having an open core and spaced projections that enable
stacked blocks to be interlocked, setback and staggered to form a
stable gravity-type retaining wall that is particularly suited for
landscaping applications. The open core extends completely through
the block from top to bottom. The block is formed by front, rear
and opposed side walls, each having parallel inside and outside
surfaces. One projection extends from the lower surface of each
side wall. The front of each projection is forward the inside
surface of the front wall to provide the setback when stacked on
other like-shaped blocks. Each block is stacked in a staggered
manner atop two other blocks. One projection of each block is
received by the open core of one of the two lower blocks. The
projections abut the inside surface of the front wall of the lower
blocks to interlock the blocks together. The block has a preferably
trapezoidal shape with a wider front wall to help accommodate the
formation of serpentine walls while maintaining a consistent front
wall appearance. The block can be used to make serpentine walls
with straight and curved portions with a relatively constant
pitch.
[0017] One advantage of the present interlocking masonry wall block
is that the thickness of the integral projections is not related to
the desired amount of setback for each course of blocks. A
retaining wall application requiring a half-inch setback per course
can have projections that are one or two inches thick. These
thicker projections are more structurally sound and not prone to
chipping and cracking. The block can be relatively short in height
to produce a block that is light weight and easy to handle.
[0018] Another advantage of the present interlocking masonry wall
block is that the block can be kept relatively short so that it can
be more easily integrated into gradually sloping terrain. The
smaller height allows more frequent steps to be incorporated into a
particular wall design so the blocks do not rise up above ground
level a great deal. This produces a more aesthetically pleasing
wall that fits and blends into the natural terrain. The blocks also
make more efficient use of material.
[0019] A further advantage of the present interlocking masonry wall
block is that the integral projections are located away from the
rear and front edges of the block. By locating the projections in
this manner, they are less likely to be damaged if the block is
dropped or bumped during transport. During shipping, the bottom
layer of blocks are inverted to lay flat on the floor, truck bed or
shipping pallet. The projections of one block fit into the openings
of the other blocks. The various columns and rows of block are
arranged flush against adjacent columns and rows of blocks to
provide a solid mass of blocks. The projections are also protected
by the lower blocks during use so that they are not exposed to the
earth and air. This keeps the projections dry and away from the
acidity of the earth, which improves the life expectancy of the
block and retaining wall formed by the blocks.
[0020] A still further advantage of the present interlocking
masonry wall block is that the integral projections are relatively
thick and relatively tall. As stated above, the projections can be
relatively thick or long because they are not dependent on the
desired setback. This increased thickness enables the projections
to have an increased height without compromising their structural
strength. The projections provide a sufficiently tall abutment to
easily and consistently align the block over the lower course of
blocks. This reduces the amount of misaligned blocks, and improves
the strength and aesthetic uniformity of the retaining wall.
[0021] A still further advantage of the present interlocking
masonry wall block is that they produce serpentine walls with
varying convex and concave shaped portions. The size and shape of
the open cores allow the smaller, spaced projections to fit into
the open cores of the blocks of the lower course. Adjacent blocks
can be oriented to form a continuous wall with curves and straight
portions that gradually increase or decrease in radius.
[0022] A still further advantage of the present interlocking
masonry wall block is that the integral projections produce a
relatively uniform amount of setback for straight and curved
portions of the wall. Even though the setback increases slightly in
concave curved portions of the wall and decreases slightly in
convex portions of the wall, this change in setback occurs evenly
and gradually as the radius of the curve increases. Discontinuities
between adjacent blocks are avoided. In addition, the pitch of the
wall is relatively constant for straight and curved portions of the
wall. The wall leans back a slightly increased amount in concave
portion and less in convex portions so that a relatively constant
pitch is achieved throughout the entire serpentine wall. This
uniform setback and relatively constant pitch enables more courses
of blocks to be used in many serpentine walls, and helps produce a
more stable serpentine wall where the combined weight of the wall
and earth pressure remain within the footprint of the block.
[0023] A still further advantage of the present interlocking
masonry wall block is that the integral projections allow the
blocks forming one course to have a varying amount of lateral
offset with relation to the course of blocks upon which they are
stacked. The retaining wall can more easily avoid obstructions,
such as a sump pump discharge pipe. The block can also be arranged
to allow drain pipes to pass through the middle of the wall. This
flexibility also allows one course of blocks to be laterally offset
to accommodate the ledge or sill of a building. Thus, the present
block facilitates the construction process and the ability to use
the block in a wide variety of locations.
[0024] A still further advantage of the present interlocking
masonry wall block is that the integral projections provide
additional resistance to lateral side-to-side movement of the
block. The blocks can easily be stacked so that one of the
projections engages the inside surface of one of the side walls of
a block beneath it. Accordingly, side-to-side movement is resisted
not only by the adjacent blocks in the same course or tier, but by
the blocks above and below it as well. Should one block in a given
course shift or move out of abutting alignment with one of its
adjacent blocks, then the remaining blocks in that row would still
be held in place by the blocks above or below it. The projections
are particularly helpful in holding the end blocks of the wall in
place where the block would otherwise be free to slide laterally
and out of place, or off the wall altogether.
[0025] A still further advantage of the present interlocking
masonry wall block is that an entire serpentine wall can be built
from a plurality of like-shaped blocks. The need for only a single
block design results in reduced manufacturing, inventory, shipping
and construction costs. The single block design also makes it
easier to design a serpentine wall that is integrated to the shape
of a specific and unique landscape setting.
[0026] A still further advantage of the present interlocking
masonry wall block is its reduced weight. The open core design
removes about thirty percent (30%) of the materials and weight of
the block so that they are easier to handle during manufacture,
shipping and construction. The open core design also reduces
material costs which can be passed on to the consumer.
[0027] Other aspects and advantages of the invention will become
apparent upon making reference to the specification, claims and
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is an elevated view of a house built to a unique
landscape setting with a gradually sloping and contoured hill that
feeds down to the level of the backyard patio of the house and a
pre-existing tree.
[0029] FIG. 2 is an elevated view showing a three foot high
serpentine retaining wall constructed from a plurality of the
present like-shaped, interlocking masonry wall blocks, and
integrated into the natural contours of the hill and unique
landscape setting of the house.
[0030] FIG. 3a is a cross sectional view of FIG. 2 taken along line
3a-3a showing a straight wall section having a pitch of about
Ps=5.degree..
[0031] FIG. 3b is a cross sectional view of FIG. 2 taken along line
3b-3b showing a high radius, convex curved portion of the wall
having a pitch of about Phr=2.degree..
[0032] FIG. 3c is a cross sectional view of FIG. 2 taken along line
3c-3c showing a high radius, concave curved portion of the wall
having a pitch of about Phr=9.degree..
[0033] FIG. 4 is an elevated, front perspective view of the
interlocking masonry wall block showing the trapezoidal shape of
the upper surface and open core of the block.
[0034] FIG. 5 is a lowered, front perspective view of the
interlocking masonry wall block showing the trapezoidal shape of
the lower surface, the open core of the block, and its rectangular
shaped integral projections.
[0035] FIG. 6 is a front view of the interlocking masonry wall
block.
[0036] FIG. 7 is a top view of the interlocking masonry wall
block.
[0037] FIG. 8 is a bottom view of the interlocking masonry wall
block showing the orientation of the offset projections relative to
the inside surface of the front wall of the block.
[0038] FIG. 9 is a side view of the interlocking masonry wall
block.
[0039] FIG. 10 is a top view of two courses of the present
like-shaped interlocking blocks arranged in a straight
configuration with the blocks in the upper course having an offset
alignment to create an opening for a drain pipe, the blocks on the
right being in about a full right alignment and the blocks on the
left being in about a full left alignment.
[0040] FIG. 11 is a top view of two courses of the present
like-shaped interlocking blocks arranged in a concave curve
configuration that gradually increases from a low radius curve,
through a medium radius curve, to a high radius curve.
[0041] FIG. 12 is a top view of two courses of the present
like-shaped interlocking blocks arranged in a convex curve
configuration that gradually increases from a low radius curve,
through a medium radius curve, to a high radius curve.
[0042] FIG. 13 is a top view of a convex shaped retaining wall
formed by the present like-shaped, interlocking masonry wall
blocks, with a pitch of Ps=1 in the straight section, and about
Pmr=0.7 in the medium radius section, and about Phr=0.4 in the high
radius section.
[0043] FIG. 14 is a top view of a convex shaped retaining wall
formed by a conventional rear flange, interlocking masonry wall
blocks, with a pitch of Ps=1 in the straight section, and about
Pmr=1.2 in the medium radius section, and about Phr=1.3 in the high
radius section.
[0044] FIG. 15 is a top view of a concave shaped retaining wall
formed by the present interlocking masonry wall blocks with a pitch
of Ps=1 in the straight section, and about Pmr=1.4 in the medium
radius section, and about Phr=1.8 in the high radius section.
[0045] FIG. 16 is a top view of a concave shaped retaining wall
formed by a conventional, rear flange, interlocking masonry wall
blocks with a pitch of Ps=1 in the straight section, and about
Pmr=1.4 in the medium radius section, and about Phr=2.0 in high
radius section.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0046] While this invention is susceptible of embodiments in many
different forms, the drawings show and the specification describes
in detail a preferred embodiment of the invention. It should be
understood that the drawings and specification are to be considered
an exemplification of the principles of the invention. They are not
intended to limit the broad aspects of the invention to the
embodiment illustrated.
[0047] FIG. 1 shows a house 10 with a walkout basement leading to a
patio 12 constructed in the backyard of the house. The house 10 has
a concrete foundation 14 which transitions to brick 16 along a sill
18 at the top of the foundation. The house is constructed into a
hill 20 that levels off to a particular ground level 22 in the
backyard of the house. The hill 20 and its terrain 30 and natural
plant life 24 form a unique landscape setting 32 around the house
10.
[0048] The present invention relates to a masonry block 40 for
constructing serpentine retaining walls with straight and curved
portions, such as the landscape retaining wall 140 shown in FIG. 2.
The serpentine wall 140 is easily integrated into a variety of
landscape settings 32. The like-shaped blocks 40 have a setback, as
discussed below. A degree of setback is maintained throughout the
entire serpentine wall 140. As discussed below, the setback impacts
the degree the wall is pitched or leans into the hill 20. As shown
in FIG. 3a, 3b and 3c, the amount of pitch (P) in the wall 140 is
somewhat less in convex curved portions of the wall and somewhat
greater in concave portions of the wall relative to the pitch in
straight portions of the wall.
[0049] An individual block 40 in accordance with the present
invention is shown in FIGS. 4-9. The block 40 has a main body 42
with upper 44 and lower 45 surfaces. The upper 44 and lower 45
surfaces are generally parallel to each other. When laid in place
on a horizontal supporting surface, the upper 44 and lower 45
surfaces are horizontal as well. The main body 42 includes a front
wall 51, a rear wall 52, and opposed side walls 53 and 54. Each
wall 51-54 is integrally formed to its two adjacent walls during
the molding process. Each wall 51-54 has an inside 61 and an
outside 62 surface. Each wall has a wall width of roughly two (2)
inches between its inside 61 and outside 62 surfaces. The upper 44
and lower 45 surfaces of each wall 51-54 have a relatively smooth
masonry finish. The walls 51-54 are solid and form continuous
surfaces 44, 45, 61 and 62. The outer surface 62 of the front wall
51 is roughened to give it a natural cut or chipped stone finish. A
conventional masonry material for landscape retaining wall blocks
is used to form the block 40. A single block 40 weighs about twelve
pounds.
[0050] The block 40 has a generally trapezoidal shape as best shown
in FIGS. 7 and 8. The inside 61 and outside 62 surfaces of the
front 51 and rear 52 walls are parallel, and perpendicular to the
upper 44 and lower 45 surfaces. The inside 61 and outside 62
surfaces of the side walls 53 and 54 are also perpendicular or
vertical to the upper 44 and lower 45 surfaces. The block 40 has a
height of about four (4) inches and a depth of about eight (8)
inches. The width of the block at its front wall 51 is roughly
twelve (12) inches from the outer surface 62 of each side wall 53
and 54. The width of the block at its rear wall 52 is roughly ten
(10) inches from the outer surface of each side wall 53 and 54.
Each side wall 53 and 54, and its respective inside and outside
surfaces 61 and 62, converge toward the other at an angle of about
seven degrees (7.degree.) as it extends toward the back wall 52.
The outside surface 62 of the front wall 51 has beveled ends 65.
The surface of these ends 65 angle back toward the rear of the
block. The outside surface 62 of the angled ends 65 meet the
outside surface of the side walls 53 or 54 along edges 67. The
outside surface 62 of the rear wall 52 meets the outside surface of
the side walls 53 or 54 along edges 68.
[0051] The block 40 has an open core or interior 80 that extends
completely through the block from its upper surface 44 to its lower
surface 45. The open core 80 is defined by the inside surfaces 61
of the front, rear and side walls 51-54. The open core 80 has a
generally trapezoidal shape that is smaller in size and similar to
the trapezoidal shape formed by the outer surface 62 or perimeter
of the block 40. The open core 80 has a width at its front of about
seven and a half (71/2) inches, and a width at its rear of about
six and a half (61/2) inches. The open core 80 is about four (4)
inches deep taken along a line perpendicular to the inside surfaces
61 of the front and rear walls 51 and 52. The comers 82 of the open
core 80 are rounded to a radius of roughly three-quarters (3/4) of
an inch. One of ordinary skill in the art should readily appreciate
that the volume of the core can vary, but is preferably maximized
to decrease the weight and material cost of the block without
impairing the strength, integrity and manufacturability of the
block. Similarly, the actual shape and dimensions of the core 80
can vary, provided the core maintains its ability to receive the
lug-shaped projections of another block 40, as discussed below. The
open core 80 should not contain any obstruction that would
interfere with the desired ability to receive these lugs.
[0052] Two integral lug-shaped projections 100 and 101 extend from
the lower surface 45 of the block 40. The projections 100 and 101
have front 111, rear 112 and opposed side 113 and 114 surfaces.
These surfaces are generally flat and perpendicular to the lower
surface 45 of the block and parallel to the inside and outside
surfaces 61 and 62 of the walls 51-54, respectively. Each lug 100
and 101 has a bottom surface 115 that is generally parallel to the
lower surface 45 of the block 40. Each lug 100 and 101 has a width
of about one (1) inch from side 113 to side 114, and a length or
thickness of about one and a half (11/2) inches from front 111 to
rear 112. Each lug 100 and 101 has a height of about five-eighths
(5/8) of an inch, and its comers and vertical edges 117 are rounded
to a radius of about seven-sixteenths ({fraction (7/16)}) of an
inch. One of ordinary skill in the art should readily appreciate
that the size and shape of the lugs 100 and 101 can vary provided
they maintain their strength, integrity and manufacturability.
[0053] Each projection 100 and 101 is generally centered between
the inside 61 and outside 62 surfaces of its respective side wall
53 or 54. Each projection 100 and 101 has a portion 118 positioned
forward or in front of the inside surface 62 of the front wall 51.
This portion 118 provides an amount of setback 120 for the block
40. The perpendicular distance between the front surface 111 of
each projection 100 and 101 and the inside surface 62 of front wall
51 is the setback dimension 120. In this embodiment, the setback
dimension 120 is shown to be about one-quarter (1/4) of an inch.
The setback 120 is the same for both projections 100 and 101.
However, it should be understood that the setback dimension 120
could be larger or smaller without departing from the broad aspect
of this present wall block invention. Each projection 100 and 101
has a centerline 119. This centerline 119 is shown perpendicular to
the inside and outside surfaces 61 and 62 of the front wall 51, but
could be parallel to the inside and outside surfaces of its
respective side wall 53 or 54.
[0054] The like-shaped blocks 40 are structured to be laterally
aligned in an abutting side-by-side engagement, and vertically
aligned in a staggered, stacked manner so that one block rests atop
two other blocks. When arranged in this manner, the blocks 40 form
a multi-tiered wall 140, such as the wall shown in FIG. 2. The wall
140 is typically constructed one course at a time. Once a lower
course 141 is set in place, an upper course 142 is placed on top of
it. The blocks 40 can be arranged to form walls 140 having straight
wall portions 150 as in FIG. 10, concave curved wall portions 160
as in FIG. 11, and convex curved wall portions 170 as in FIG. 12.
The concave portions 160 have a degree of curvature that ranges
from a low radius curve 161, to a medium radius curve 162, to a
high radius curve 163. Similarly, the convex portions 170 range
from low 171, to medium 172, to high 173 radius curves. The blocks
40 can be arranged to gradually or rapidly increase or decrease the
radius of the curvature of the concave or convex curves 160 or 170,
which enables the wall 140 to conform to the unique landscape
setting 30.
[0055] When erecting a wall 140, a gravel or sand bed 179 is
preferably formed to level the terrain 32 where the first course
141 of blocks 40 is to be laid. In each course 141 or 142, the
front and rear side edges 67 and 68 of laterally adjacent blocks 40
are aligned. The front edges 67 are aligned in abutting engagement
in straight wall portions 150 as shown in FIGS. 2 and 13, low
radius concave wall portions 161 as shown in FIGS. 11 and 15, and
all convex wall portions 170-173 as shown in FIGS. 12 and 13. The
front and rear edges 67 and 68, as well as the entire outside
surfaces 62 of side walls 53 or 54 of adjacent blocks 40 are
flushly aligned in abutting engagement for a medium radius concave
wall portions 162 as shown in FIG. 11. High radius concave wall
portions 163 are formed by aligning the rear edges 68 of adjacent
blocks 40 as shown in FIG. 11. The lower surface 45 of each block
40 in the first or lowest course 141 is placed at the same
horizontal level, which is deemed the ground level 22. In the first
course 141, the projections 100 and 101 can extend into the gravel
or sand bed 179. The upper surfaces 44 of the blocks 40 forming the
lower course 141 form a generally horizontal platform upon which
the upper course 142 can be stacked. The lower surface 45 of each
block 40 in each stacked, upper course 142 is placed on and rests
on the upper surfaces 44 of the blocks in the lower course 141 upon
which it is placed.
[0056] An interlocking fit is achieved between the like-shaped
blocks 40 in adjacent upper 142 and lower 141 courses. Each block
40 in the upper course 142 is laid in a staggered manner relative
to the lower course 141 so that the upper block is placed atop two
lower blocks. Each block 40 in the upper course 142 is placed so
that one of its lug-shaped projections 100 ort 101 extends into and
is received by the open core 80 of one of the lower blocks. The
other projection 100 or 101 extends into and is received by the
open core 80 of an adjacent lower block. The front surface 111 of
each lug 100 and 101 of the upper block 40 abuts the inside surface
61 of the front wall 51 of its respective lower block. This
abutting engagement between the upper and lower blocks 40 in
adjacent courses 141 and 142 forms the interlock that prevents the
block in the upper course 142 from moving forward. This interlock
enables the blocks 40 in the upper courses 142 to resist the
pressure of the earth and hill 20 behind the wall 140.
[0057] A further aspect of the interlocking fit is achieved by
aligning the block 40 in the upper course 142 so that one of its
projections 100 or 101 abuts the rounded comer 82 or inside surface
61 of the side wall 53 or 54 of the block in the lower course 141.
When in a full right 181 or full left 182 alignment as shown in
FIG. 10, the blocks 40 in the upper course 142 are prevented from
sliding sideways or laterally relative to the blocks in the lower
course 141. The block 40 in the lower course 141 experiences a
similar resistance to movement in the opposite lateral direction. A
block in a middle course may experience a resistance to both right
and left movement.
[0058] Adjacent blocks 40 in a particular course 141 or 142 can
also be arranged in an offset alignment 185. One block 40 can be
positioned in a fall right alignment 181 and its adjacent block can
be position in a full left alignment 182 to form a gap or opening
187 between the two blocks shown as in FIGS. 2 and 10. The maximum
amount of offset of the preferred embodiment of the block 40 is
about six (6) inches. The ability to laterally offset adjacent
blocks 40 to create openings 187 in the otherwise solid wall 140
enables the wall to accommodate drainage pipes, gutter down spouts,
sump pump piping or other obstacles, and helps prevent excessive
water building up behind the retaining wall.
[0059] As discussed above, the projections 100 and 101 produce an
amount of setback 120 between the upper and lower courses of blocks
141 and 142. When the wall 140 is properly constructed, the blocks
40 in the upper course 142 are set back a predetermined amount 120
from the blocks on which they are placed. In the preferred
embodiment, the outer surface 62 of the front wall 51 of the upper
block 40 is set back about one quarter (1/4) inch from the outer
surface of the lower blocks on which it is placed. The setback
dimension 120 directly affects the amount or degree of pitch P in
the wall 140. The setback 120 of each block 40 in the upper course
172 is substantially the same when measured along the centerline
119 of each projection 100 or 101. When the blocks 40 form a
straight wall segment 150, the height of the blocks 40 and the
setback amount 120 determine the pitch of the wall. The amount of
pitch can vary slightly in an actual construction setting due to
the present of dirt or other debris, which can come between the
lugs 100 and 101 of the upper block and the inside surface 61 of
the front wall 51 of the lower block. When the blocks 40 form a
curved wall segment 160 or 170, the pitch of the wall varies. For
example, as shown in FIG. 13, a wall 140 having a pitch in straight
wall section of Ps=1.0, should have a reduced pitch in a medium
radius convex section 172 of about Pmr=0.7 times Ps, and a high
radius convex section 173 of about Phr=0.4 times Ps. As shown in
FIG. 15, the wall 140 should have an increased pitch in a medium
radius concave section 162 of about Pmr=1.4 times Ps, and a high
radius concave section 163 of about Phr=1.8 times Ps. A more
consistent pitch is believed to occur with this wall 140 than in
other conventional walls, such as the wall shown in FIGS. 14 and
16, because the lug-shaped projections 100 and 101 do not span the
entire width of the block 40, and are located toward the front wall
51 and inwardly from the outside surfaces 62 of the side walls 53
and 54.
[0060] The top course of blocks 40 in the landscape retaining wall
140 is preferably capped by cap stones 195 to cover the open cores
80 of the blocks 40 that form the top course or portion of a
course. These cap stones 195 provide a finished look to the wall.
These cap stones 195 can be glued or otherwise adhered to the upper
surface 44 of the blocks 40.
[0061] While the invention has been described with reference to a
preferred embodiment, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted without departing from the broader aspects of the
invention.
* * * * *