Note: Descriptions are shown in the official language in which they were submitted.
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Field of the In~ention
This invention relates to an improved gravi~y retaining wall
facing structure derived from horizontally disposed stacked coursas
of like blocks ox modules.
More particularly this invention relates to an improved
interlocking block or module for repeated use in a gravity
retaining wall system derived from such blocks or modules and to
improvements in the characteristics of the retaining wall system so
constructed therefrom and in the method of installing same.
Background of the Invention
Many known gravity retaining wall systems utilize like
interlocking blocks or modules of a specific geometry disposed in
end-to-end aligned relation and in horizontally stacked courses.
The aligned blocks or modules of the upper course bridge the joints
or separation between adjacent aligned blocks or modules of the
lower course.
A facing wall so constructed generally resists overturning due
to the ~orces generate~ by the confined backfill or embankmen~ by
reason of the combined weight or mass of the blocks or modules but
where the blocks or modules are of lighter weight or reduced mass,
or the wall exceeds a certain height, the introduction of headers
or tie-hack blocks or other suitable stabilizing soil elements or
anchors, such as grid-like plastic sheeting or an equivalent metal
mesh, are required to preserve the integrity of the installa~ion.
The joints between the courses of overlapped blocks or modules
are not normally mortared but are esta~lished by a mechanical
interlock so as to present a substantially integral uni~orm facing
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wall formation through mating recesses and projections presented by
the body portions of the respective like blocks or modules.
The character and tolerances of the mechanical in~erlocks
usually afford the assembled blocks or modules a degreP of freedom
in one direction to shift longitudinally relative to each other
under applied loads generated by frost heaving or earth settling,
which shifting and subsidence act to preserve the structural
integrity and serviceability of the structure over an extended
period of time.
The configuration or shape of the block body, the "geometry",
the character of the mechanical interlock and the dimensions of the
block or module, all affect the efficiency of the productionl
transport, and the installation of the blocks or modules as well as
the stability of the structure.
Examples of gravity retaining wall structures are detailed in
the following patents: Canadian patent no. 1188116, United States
patent no. 2313363, United States patent no. 41g3718, and German
patent 2755833.
An interlocking facing wall block or module for a gravity
retaining wall system is usually formed or moulded from a suitable
concrete mix to present a body portion shaped to provide generally
parallel upper and lower bearing surfaces, front and rear facings,
and side or end surfaces, with an upstanding or outstanding
projection for mating registration with integral recesses presented
thereto by an adjacent overlying or underlying block or module.
Such interlocks, together with the weight or mass of the
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installation, offer increased resistance to the applied loads of a
low embankment.
When higher loads are generated by the contained embankment or
where a surcharge is applied to a wall by near~y road or rail
traffic increased resistance ~o such loads can be produced by
including headers or tie back modules a~ the base and a~ selected
intervals throughout the wall.
The backfill deposits of soil and other components in elevated
embankments can b~, and now preferably are, suitably rein~orced and
stabilized by appropriate grid-like plastic sheeting, metal
lattices, or other equivalent elements, which disperse or inhibit
the thrust of the forces generated.
Also the facing wall may be, and preferably will be, suitably
tied to such soil reinforcement or other anchoring members to still
better anchor and preserve the installation as well as permit the
use of lighter weight blocks or modules and thereby increase the
efficiency of the undertaking.
Where a curvate wall section is called for blocks or modules
which have a generally overall rectangular or rectilinear
configuration in plan view present serious disadvantages, since
when placed to define the curved section of the wall ad~acent
blocks of a given course leave wedge shaped gaps therebetween.
Such gaps, i interior and left unblocked, are likely to
permit the escape of backfill with the consequent disturbance or
unsettling of the embankment.
When an exterior curved section is installed such e~posed gaps
encourage growth of plant life with root penetration prying the
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blocks or modules apart as well as invite burrowing, leading to
disturbance and deterioration and an unsightly appearance.
It is also important to note that the specific character of
the interlock of the blocks or modules may ~hemselves limit the
curved section to a relatively large radius in order to maintain
the requisite interlocking function.
Objects of the Invention
One object of this invention~ therefore, is to provide an
improved interlocking block or module for a gravity retaining wall
as outlined above which block or module interengages with blocks
aligned in one horizontal course as well as with the bri~ging
blocks aligned in ad~acent overlying and underlying horizontal
courses in a simplified manner while increasing the resistance to
the forces of displacement or movement imparted to one or several
blocks, whereby the overall integrity and stability of the
installation is enhanced.
More particularly it is a very important object to provide an
improved block which through the simplified interlocking structuxe
disclosed facilitates the ready formation of a stable curvate
retaining wall section where required over a range of arcs, whether
an inside or outside curva is required, from which the escape of
any contained backfill or embankment constituents will be minimized
or substantially blocked.
Still more particularly it is an important objec~ to provide
such an interlocking block or module or a facing wall as aoresaid
affording alternative block or module dispositions to provide at
leas~ two differen~ distinctive artistic expressions or ~looks~l.
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It is also of a very high priority to create and present a
range of lighter to heavier weighted blocks or modules to meet
varying embankment conditions all of which will have substantial
appeal architecturally, yet favourably compete with similar
structures originating with other sources, but hava the effect of
reducing the overall cost of the project.
Yeatures_oi the Inventîon
One feature of this inven~ion resides in providing a modified
geometry for such a block or module which includes presenting a
socket at one end of the body portion and a matching projection
outstanding from the other end for the mating reception within such
socket of a matching projection of a like blo~k aligned therewith
for disposition in a horizontal course and for the mating
registration of such pxojection within the matching socket of
another like block likewise aligned therewith for disposition in
such horizontal course, and with the lower bearing surface of the
body portion presenting a recess in a region centrally thereof and
with the outstanding projection presenting an extension or
anchoring means upstanding from the upper bearing surface matching
such recess for the mating registration with such recess of the
matching extension of a like block aligned for disposition in an
underlying course and for the mating registration of such extension
within the recess of a like block aligned for disposition in an
overlying course.
Thus, so structured, movement imparted by the thrust of
embankment forces to any one block or segment of a facing wall will
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be increasingly resisted by the transmission of such forces to all
adjacent blocks through their aligning interconnections.
Another feature re~ide~ in so shaping the body portion and
respective socket and projection such thak they cooperate with
respective like projections and sockets as in a hinge for relative
swinging movement about a substantially vertical or upright axis,
and likewise shaping the extension and matching recess so as to
form a pivot for relative swinging movement of the overlying
bridgin~ block about the same axis, whereby such blocks can be
aligned along a curvate or sinuous path in each course and a stable
curvate or sinuous section of the facing wall constructed.
Still another feature resides in so shaping the recess of the
lower surface of the block body to present a channel formation to
the upstanding extension dimensioned to afford a sliding as well
as a rotary fit to further accommodate adjustment of the overlying
course of blocks to the underlying course, especially in
constructing a curvate wall section, thereby further facilitating
installation of the desired facing wall.
It is another feature of this invention to provide the socket
in the form of a ~barrel~ as in a ~hinge~ preferably ex-tending from
the lower bearing surface to the upper bearing surface and with the
outstanding projection or ~pintle~ preferably matching that extent
whereby the gap between aligned blocks in a horizontal course can
be minimized, if not elimina~ed, whether assembled in a straight
or cuxvate or sinuous path, and thereby contain the embankment or
backfill.
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Still another feature resides in so locating the recess with
reference to the front and rear facings of the block body that the
recess and upstanding extension will be offset in relation thereto
so that each su~cessive course can be set back from the course next
below to provide an inclined profile and thereby increase the
stability of the structure.
Another important feature resides in contouring the front and
rear facings so as to taper ~owards the ends of the block or module
with the socket and projection, respectively, presented where those
facings converge, thereby affordi.ng a greater arc of relative
swinging movement between aligned blocks of a given horizontal
course and thereby extend the limit of the proposed curvature to be
included in the retaining or facing wall of the installation.
Still another feature follows from the aforesaid-kapered block
geometry wherein the main body portion can be given an increased
width centrally from front to rear and the facings thereof suitably
contoured and with the central region of the body presen-ting an
aperture or cavity to thereby decrease the weight or mass without
substantially affecting the compressive strength.
It is also feature of this invention to provide an improved
method of constrllcting a retaining wall structure, and particularly
a curva~e retaining wall structure, deri~ed from a plurality of
such like blocks or modules disposed end to end in aligned
horizontal courses and stacked one upon the o-ther so that aligned
adjacent blocks of each horizontal course are securely in-terengaged
with each other as well as with the aligned bridging blocks o~ the
next adjacent stacked horizontal course that includes:
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(a) the step of excavating the soil ko a selected depth
and levelling same so as to establish a base
suitable for supporting the retaining wall
structure;
(b) the step of laying upon the established levelled
base a first course of like structural blocks
oriented along a selected path to present the
projection extensions thereof uppermost and then
aligning and fully registering the projections of
blocks within the sockets of like adjoining blocks
o~ such course;
(c) the step of so laying upon the blocks of the first
course a second course of like hlocks oriented to
present ~he like facings thereof in the same
direction and the recesses thereof to register over
the projection extensions of the lower course
thereby bridging the separations between adjacent
blocks of the lower courses and aligning and fully
registering the projections of the blocks of the
course within the sockets of like adjoining blocks
thereof; and
(d) repeating the lattex step until the desired number
of courses have been laid.
Descriptlon of the Invention
These and other objects and features of the invention will be
perceived from the following description of the preferred
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embodiments of the invention whic~ is to be read in conjunc-tion
with the sheets of drawings illustrating same, wherein:
Figure 1 is a perspective view of an improved block embod~ing
the invention tak~n from a point upwardly and to the right ~hereof;
S Figure 2 is a perspective view of the block of Flgure 1 taken
from a point rearwardly and to the right thereo~;
Figure 3 is a top plan view of the block of Figure 1;
Figure 4 is a bottom plan view of the block of Figure 1;
Figure 5 is a front elevational view of the block of Fi~ure 1;
Figure 6 is a rear elevational view of the block of Figure 1;
Figure 7 is a side elevational view of the block of Figure 1
taken from the right thereo;
Figure 8 is a side elevational view of the block of Figure 1
taken from the left thereof;
Figure 9 is a perspective view of one embodiment of a gravity
retaining wall constructed in accordance with the invention from
the improved block of Figure l;
Figure 10 is a perspective view of a curvate section of a
gravity retaining wall constructed in accordance with the invenkion
from the improved block of Figure 1;
Figure 11 is a plan view of the retaining wall of Figure 9
wherein the internal structure is illustrated in broken lines;
Figure 12 is a plan view of the retaining wall of Figure 10
wherein the internal structure is illustrated by broken lines; and
Figure 13 is an elevational view of the improved blocks as
they would be stacked in three courses in the manner illustrated by
Figure 11.
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The improved block or module 10 embodying the invention is
depicted in Figures 1 through 8, inclusive, and includes a body
portion 12 bounded by front and rear facings generally indicated at
14 and 16, respectively, opposed sides or ends indicated at 18, 20,
respectively, and by generally parallel upper and lower bearing
surfaces 22, 24, respectively.
In the preferred embodiment of the invention opposed forwardly
disposed facings 26, 28, respectively, flank central front facing
29, and rearwardly disposed facings 30, 32, respectively, flank
central rear facing 33, with facings 26, 30 converging towards end
18 of body portion 12, and likewise facings 28, 32, converging
towards end 20 of body portion 12.
It will be understood that the configuration or shaping to be
applied to central front and rear facings 29, 33 and flanking
facings 26, 28 and 30, 32r respectively, can be modified to achieve
a range of artistic expression and thereby provide several distinct
appearances or "looks"~
In the preferred embodiment, body portion 12 of block or
module 10, which can be formed with a solid core, is illustrated
with a central aperkure or cavity 34, opening to upper and lower
- bearing surfaces 22, 24, respectively, minimizing the required
materials used in moulding or otherwise constructing block 10, and
thereby reducing the weight thereof as well as enhancing the
strength to weight ratio of the block; all in a manner known to
those skilled in the art.
When constructing a gxavity retaining wall from a plurality of
like blocks 10, such blocks a.re disposed end to end in alignment in
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stacked horizontal ~ourses upon a suitably comported and levelled
base, and adjacent block~ of each horizonta~. course are interlocked
with each other as well as interlocked with blocks of the nex~
adjacent overlying horizontal course. ~ccordingly, body portion 12
5of block 10, in the preferred embodiment, presents an anchoring
means such as extension or pivot 36 upstandi.ng above upper bearing
surface 22l and a recess 38 within lower bearing surface 24. In
the preferred embodiment extension or pivot 36 has a configuration
and extent for the mating reception and registration within recess
lO38 presented by lower bearing surface 24 of a like block in an
overlying course, so as to establish an interlock between
successive courses of the resultant retaining wall structure, as
will hereinafter be explained.
In the preferred embodiment, recess 3B within lower bearing
15surface 24 of body portion 12 extends from end to end and defines
a channel 39 running in a direction parallel to median plane 41 of
the block body, as best illustrated in Figure 2.
Further, in the preferred embodiment, recess 38, in the ~orm
of channel 39 within lower bearing surface 24, opens to -those
20regions where facings 26, 30 converge and facings 28, 32 converge.
Moreover, extension or pivot 36, upstanding from upper bearing
surface 22 of body portion 12 is spaced from front facing 14 of
body portion ~2 a greater distance measured from front facing 14
than the extent to which the recess 38 is located so that extension
25or pivot 36 is offset slightly rearwardly in relation to recess 38.
This arrangement dictates that each superior course o like
blocks when stacked one upon the other with front faci.ngs 14
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positioned forwardly will be offset rearwardly in relation to the
next below course, as best illustrated in Figur~ 13 of the
drawings~ providing an inclined pro~ile to the retaining wall
constructed, as well as enhancing the stability th~reof.
In order to interlock adjacent blocks of each horizontal
course with respect to one another, body portion 12 of block or
module 10 presents a proiection 40 outstanding from end 18 and a
socket 42 presented by opposed end 20.
In the preferred embodiment projection 40 outstanding from
end 18, and socke~ 42 presented by opposed end 20, are spaced
uniformly rearwardly from centra]. front facing 29 of body portion
12.
It is to be understood that the configuration and extent of
projection 40 and socket 42 are matched so as to matingly register
or interengage when aligned and thereby restrain the relative
displacement of ad~acent blocks of a given course with respect to
one another.
In the preferred embodiment of the invention extension or
pivot 36 upstanding above upper bearing surface 22 is integral with
projection 40 but could be constituted by a separable pin insert.
This hinge-like structure occupies the separation between
ad~acent blocks of a given course and extends from lower surface 44
of projection 40, which is coplanar with inner surface 45 of recess
38, upwardly throughout the remaining depth of body portion 12 and
terminates in extension or pivot 36, which is sufficient to
register within recess 38 of an overlying like block 10~
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The block or module 10 embodying the invention can be used in
constructing gravity retaining walls having stra.ight or curved
sections.
Projection 40, or the ~pintle~ of the "hinge", in the
preferred embodiment, has a part c~lindrical configuration with its
axis 47 extending generally ver~ically whereas socket 42 is the
"barrel~ of the ~hinge~ presenting an open sided cavity of a
matching part cylindrical configuration.
When projection or ~pintle~ 40 is inserted into socket or
"barrel" 42 a hinge~like structure is established which affords a
range of swinging movement between aligned blocks, and which is
increased by the tapering of facings 26, 28, 30, and 32,
respectively, flanking the aforesaid "hinge" components. Thus,
curved wall sections can be readily constructed or included in an
installation as will hereinafter be e~plained.
Figures 9 and 11 reveal a gravity retaining wall structure 52
derived from like blocks or modules 10 embodying the invention
disposed in aligned horizontal courses and stacked one upon another
so that adjacent blocks in each horizontal course are interlocked
as well as interlocked with the overlying blocks or the underlying
blocks of the ne~t adjacent horizontal courses.
Similarly, Figures 10 and 12 disclose a modified gravity
retaining wall 58, but illustrating a curvate section derived from
improved blocks or modules 10.
Preparation for the construction or installation of gravity
retaining wall 52 illustrated in Figures 9 and 11, requires that
the site be cleared and the soil or overburden be excava-ted and a
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granular base o~ suitable materials of sufficient dep-th be
deposited and compacted and levelled in all directions.
A first course of blocks or modules 10 is then laid upon the
base along a line or path de~ining ~he base of the installation
with the lower bearing surfaces of the blocks lowermost; all in the
manner outlined in the preceding description and with successive
courses of like blocks installed until the desired height of the
structure is reached.
When constructing a gravity retaining wall such as facing wall
52, successive courses of blocks/ such as 56, are to be aligned
over first course 54 so tha~ each overlying block 10 will bridge
the separation between adjacent blocks of the inferior course and
with extension or pivot 36 of the lower course of blocks 10
registered within recesses 3% of the blocks of the overlying
course, and in sliding fit, whlch affords the necessary adjustment
for efficient installation.
It will also be appreciated that the geometry of the blocks
will dictate mating in~erengagement between projections 40 and
sockets 42 of aligned blocks of each course, whereby any movement
imparted to any individual hlock or b]ocks within the retaining
wall will be transmitted to all adjacent blocks, that is to each
end and above and below with the rotary interlock accommodating
relative shifting or adjustment preserving, upon subsidence, the
overall integrity o~ the structure, and reducing the extent to
which such structure must be reinforced through use of tiebacks or
grid or mesh anchors.
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It will also be understood that by having recess 38 extending
substantially the length of body portion 12 of block or module 10,
from ~nd to end, that an upper course of blocks can be shifted
longitudinally in mated rela~ion to a lower course of blocks ovPr
a range of overlapping positions; a faature assisting in
customizing a retaining wall structure to a given site and
particularly where curvate wall sections are to be installed, all
as illustrated in Figures 10 and 12, yet adequately blocking the
separation between the aligned blocks of each course.
While constructing a curved retaining wall section for facing
wall 58 as illustrated in Figures 10 and 12, the first or lower
course of blocks 60 are set in position in the manner described
above.
It will be appreciated that mating curvate surfaces 46 and 48
of projection 40, and socket 42, respectively, accommodate rotation
until the desired angle is reached. As earlier mentioned by
suitably contouring thQ flanking facings 26l 28 and 30, 32, a wide
range of block dispositions can be proposed and curvate wall
sections readily introduced into the facade.
It can al80 be appreciated that through providing extension or
pivot 36 as a cylindrically shaped extension the rotation within
mating recess 38 is utilized in positioning the overlying block at
the required angle as i.llustrated by the disposi-tion of blocks 10
of upper course 62 with respect to lower course 60 of wall
structure 58 revealed hy Figure 12.
The relative ease by which a curvate section o~ a retaining
wall structure can be introduced can be appreciated when one
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compares the curvate wall section in Figures 10 and 12 to a curvate
wall section constructed from rectangularly shaped blocks, which
when placed adjacent to one another to form a curve present
triangularly shaped gaps therebetween. In many applications such
gaps expose soil or granular backfill, especially upon shifting,
which can be washed out by rain or by the seepage of ground waters.
Further, snow and ice can accumulate in exposed gaps leading
to prying apart of the blocks during repeated freeze-thaw cycles.
Moreover, undesirable plant life may root in the crevices, or
animals burrow into the back~ill which will not only affect the
stability but the desired "look" of the installation.
It will be appreciated that the geometry of blocks 10 are
readily incorporated into straight or curvate retaining wall
sections or combinations thereof, while maintaining the blocks in
proximity, and substantially minimizing gaps in the assembled
structure.
Finally, having regard to Figure 13, it will be observed that
by having extension or pivot 36 rearwardly offset in relation to
recess 38, like blocks stacked in horizontal courses will be
substantially uniformly set back from the next below course so that
the gravity facing wall is suitably angled to the vertical
imparting a further element of distinctiveness to the "look".
Whereas specific embodiments of the invention and features
thereof have been illustrated and described herein, those skilled
in the art may undertake or introduce alternatives or modifications
without departing from the spirit and scope of the in~ention as
defined by the appended claims.
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