The invention relates to concrete blocks, such as wet cast or dry cast concrete blocks for use in the creation of walls, including blocks having an embossed front face. More particularly, the invention relates to concrete blocks with natural stone appearance for use in the creation of curved walls, such as retaining walls.
Concrete blocks are well known for the use in landscaping applications, particularly retaining walls. Various different block configurations or shapes are known. To allow the assembly of curved walls, concrete retaining wall blocks are usually provided with a rearwardly tapered body with sidewalls that are at an angle of less than 90 degrees to the front face of the block. Stacking such blocks side by side with the angled sidewalls of adjacent blocks engaging one another results in a convexly curved wall. Concave curvatures are obtained by stacking the blocks side by side with the front edges touching, while the tapered rear ends are spaced apart. This provides significant flexibility in the creation of curved walls the radius of curvature of the wall being limited solely by the angle of the sidewalls relative to the front face. However, tapered blocks and walls built with such blocks have several drawbacks.
Straight walls built with stacked blocks of tapered shape have a substantially continuous front face, but include a pattern of multiple gaps in the back face of the wall, due to the angled sidewalls. In fact, even curved walls with a curvature less than the maximum convex curvature allowed by the taper of the blocks will always include this pattern of gaps. Consequently, tapered blocks cannot be used to build freestanding walls, since the appearance of the rear wall will be very different from the front face and will not be aesthetically pleasing due to the pattern of gaps. A freestanding wall with natural appearance on both sides is not achievable with tapered blocks. Thus, a wall block system for building freestanding curved walls is desired, wherein all sides are continuous and have a natural stone appearance.
The retaining capacity of a retaining wall is determined in part by the mass of the wall. However, the gaps formed in the rear surface of walls made with tapered blocks significantly reduce the overall mass of the wall. Thus, a wall blocks system for freestanding curved walls is desired, which maximizes the mass of the wall and minimizes any gaps between laterally adjacent wall blocks.
Molding dry cast tapered blocks with converging side walls and an embossed front face is challenging due to the need for stripping the compressed block from the mold. Dry casting uses a no slope concrete mixture which is filled into a mold cavity and compressed to sufficiently pre-consolidate the block to permit handling of the block prior to curing of the concrete mixture. After pre-consolidation, the block is stripped from the mold and transported to a curing station for curing of the concrete mixture. Stripping of the block is achieved by pushing it out of the mold with a stripper shoe which has a dual function. The stripper shoe is used during pre-consolidation to compress the dry cast concrete mixture. After pre-consolidation, the stripper shoe is used for forcing the pre-consolidated block from the mold. To produce blocks with an embossed surface structure or pattern on the front face, the stripper shoe is provided on its dry cast mixture engaging face with a negative of the three-dimensional surface structure to be produced on the block face during pre-consolidation.
Stripping the pre-consolidated block by pushing it from the mold requires a clear path for the block through the mold, which mandates the use of movable mold walls in the manufacture of tapered, embossed blocks. To facilitate handling and stacking of pre-consolidated embossed blocks and especially to minimize damage to the embossed front face during curing, the embossed blocks are usually manufactured with the front and rear faces oriented up and down in the mold, respectively. That means the sidewalls of the mold must be movable from the angled position required for the shaping of the tapered shape of the block, in order to provide a clear path of the block through the mold. Thus, embossed wall blocks for the assembly of curved walls are desired which are more easily manufactured.
It is now an object of the invention to overcome at least one of the disadvantages associated with known dry cast embossed wall blocks.
In a preferred embodiment, the invention provides a stackable concrete wall block, having a prism shaped body with front and rear faces, in a stacked orientation, top and bottom faces for placement opposite like blocks positioned above and below in a stacked condition of the wall block and at least a pair of side walls for placement opposite a like block placed side by side to the wall block, and a lip protruding from at least one of the sidewalls and coplanar with the front face for spacing the body of the block from the body of a like block placed adjacent thereto. Preferably, the front face of the block and the lip have a three-dimensional surface structure, preferably an embossed surface structure. The block is preferably a dry cast, embossed concrete block.
The lip is preferably provided on one or both of the side walls to create lateral spacing between concrete blocks stacked side by side in a wall, while providing the wall with a continuous front face. As is the case with tapered blocks, this spacing allows the assembly of curved walls. However, a prism shaped block with straight side walls and a lip is more easily manufactured than a tapered block with angled side walls, since no movable mold walls are required, when the block is a dry cast block. The lip can be achieved by way of a draw plate which is placed in the mold for filling and compression of the dry cast mixture and is pulled from the mold cavity prior to stripping. The use of draw plates in the manufacture of dry cast concrete blocks is known, but is generally used for the production of three-dimensional structures and/or undercuts on the rear face of the block.
The lip preferably has a depth which is at the maximum 50% of the overall depth of the block as measured from the front face to the back face and preferably between 5% and 50%, most preferably between 25% and 50%.
In another preferred embodiment, the dry cast concrete block further includes a connecting structure for connection of a secondary structure, such as a setback pin, a like concrete block, a veneer block, or a filler block to the rear face of the concrete block. Filler blocks are used for covering any rearward gap created in an installed condition by the lip between the block and an adjacent like block. A back to back attachment of a pair of like blocks by way of the connecting structure allows for the assembly of a two sided wall. The connecting structure is preferably a dovetail type connection with one or more female connector members provided in a back surface of the wall block and a corresponding number of complementary male connector members provided on the secondary structure to be connected to the back surface.
In a further embodiment, the invention provides a set of dry cast concrete blocks including a wall block, a filler block and a connecting structure for connecting the wall and filler blocks in a back-to-back arrangement. The wall block preferably has a prism shaped body with front and rear faces, in a stacked orientation, top and bottom faces for placement opposite like blocks positioned above and below in a stacked condition of the wall block and at least a pair of side walls for placement opposite a like block placed side by side to the wall block, and a lip protruding from at least one of the sidewalls and coplanar with the front face for spacing the body of the block from the body of a like block placed adjacent thereto. Preferably, the front face of the block and the lip have a three-dimensional surface structure, and the filler block has a prism shaped body with generally front, rear, top and bottom faces and generally parallel side walls.
In a preferred embodiment of the set of concrete blocks, the wall block has an overall width X, n protruding lips, with n=1 or 2 and each lip having a protruding width Y, the wall and filler blocks have the same depth and the overall width of the filler block is between X and X-2nY. The wall and filler blocks may have a different height.
In another preferred embodiment of the set of concrete blocks, the wall block has an overall width X, n protruding lips, with n=1 or 2 and each lip has a protruding width Y and a depth B. The wall block has a depth A and the filler block has a depth C and the overall width of the filler block is between X and X−n(Y+YC/A−B). The wall and filler blocks may have a different height.
The connecting structure is preferably in the form of a dovetail type connection with one or more male connector members provided on one of the wall and filler blocks and a corresponding number of female connector members provided on the other of the wall and filler block. Alternatively, the connecting structure may be a separate connector insertable into complementary recesses in the wall and filler blocks. However, any other connecting structure can be used, which is incorporated into or separate from one or both of the wall and filler blocks, as long as the connecting structure renders the wall and filler blocks connectable in a back-to-back orientation.
The invention will now be further described by way of exemplary embodiments and with reference to the attached drawings, wherein,
a to 9c are perspective, front elevation and top plan views of a mold frame arrangement for the dry casting of a set of short and long wall and filler blocks;
a to 10d are perspective, bottom plan, front plan and end elevation views of a wall block with a stepped lip;
a and 12b are a front and top perspective view and a front plan view of a partial wall including seven (7) stacked blocks in accordance with one aspect of the invention; and
The present application is directed to a wall block for use in retaining walls or freestanding walls, preferably a cast concrete block, more preferably a dry cast, embossed concrete block.
In a preferred embodiment as illustrated in
In the installed condition of the wall block 100, wherein the wall block 100 is stacked with like wall blocks 100 into a wall, the lip 120 provides for spacing between the bodies 110 of adjacent wall blocks 100 placed side by side, while providing the resulting wall with a continuous front surface, as shown in
The lip 120 can be provided on either one or both of the side walls 119, preferably both, to create bi-lateral spacing between the bodies 110 of wall blocks 100 stacked side by side in a straight wall (see
A wall block 100 with a prism shaped body 110 with parallel side walls 119 is more easily manufactured by dry casting than known, tapered blocks, since no movable mold walls are required.
In another preferred embodiment as illustrated in the Figures, the dry cast wall block 100 further includes a connecting structure 300 for connection of a secondary structure to the rear face 114 of the wall block 100. The secondary structure can be a setback pin, a like block, a different block, or a veneer. The different block is preferably a filler block 200 as shown in
A preferred embodiment of a filler block 200 is illustrated at different lengths in
In a further embodiment (as illustrated in the bottom portion of
A pair of interconnected wall and filler blocks 100, 200 is illustrated in each of
The protruding length Y of the lips 120 determines the radius of curvature which can be achieved by placement of the wall blocks 100 side by side in a wall with the lips 120 and the bodies 110 of adjacent blocks 100 being in engagement. The larger the protruding width Y, the smaller the minimum radius achievable. An angle a is enclosed by the side wall 119 of the wall block 100 and an imaginary line 400 connecting the free end 121 of the protruding lip 120 with the terminal edge 115 of the rear wall 114. This angle is the minimum angle at which adjacent wall blocks can be placed without forming a gap between the blocks at the front face 112. Of course, wall blocks 100 can also be placed side by side in straight alignment to form a straight wall, in which case the protruding lips 120 are in engagement, but the blocks do not touch at the rear face 114, resulting in a space between adjacent wall blocks 100 at the rear face 114. In order to provide the straight wall with continuous front and rear surfaces, filler blocks 200 are used which have the same overall width X as the wall blocks 100, as shown in
Casting of the lip 120 can be achieved by way of a draw plate 140 (see schematically in
The lip 120 preferably has a depth B, measured in a direction parallel to the associated side wall 119, which is a maximum of 50%, preferably between 50% and 5%, most preferably between 50% and 25% of the overall depth A of the wall block 100 as measured from the front face 112 to the back face 114 (see
In order to address these limitations to the depth and protruding length of the lip, the invention also provides variant of the block 100 in which a larger total protruding length Y or overhang is achieved by providing a stepped lip 120 including two or more steps 120a, 120b, as illustrated in
As illustrated in
In one embodiment of the set of concrete blocks for the assembly of curved walls of minimum radius of curvature, the wall block 100, including the protruding lips 120, has an overall width X, protruding lips 120, with n=1 or 2, each lip has a protruding width Y, the wall and filler blocks 100, 200 have the same depth and the overall width of the filler block is between X and X−2nY. The wall and filler blocks may have a different height.
In another embodiment of the set of concrete blocks, the wall block 100 has an overall width X, including the protruding lips 120, n protruding lips 120, with n=1 or 2 and each lip having a protruding width Y and a depth B, the wall block 100 has a depth A, the filler block 200 has a depth C and the overall width of the filler block 200 is between X and X−n(Y+YC/A−B). The wall and filler blocks may have the same or different heights.
The connecting structure is preferably in the form of a dovetail type connection with one or more male connector members provided on one of the wall and filler blocks and a corresponding number of female connector members provided on the other of the wall and filler blocks. Alternatively, the connecting structure may be a separate connector insertable into complementary recesses in the wall and filler blocks. However, any other connecting structure can be used, which is incorporated into or separate from one or both of the wall and filler blocks, as long as the connecting structure renders the wall and filler blocks connectable in a back-to-back orientation.
In another embodiment of the block 100, illustrated in
As illustrated in
As shown in
This application claims the benefit of priority of U.S. Provisional Patent Application No. 61/425,407 filed Dec. 21, 2010 and U.S. Provisional Patent Application No. 61/555,947 filed Nov. 4, 2011, the contents of which are incorporated herein by reference.
Number | Date | Country | |
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61425407 | Dec 2010 | US | |
61555947 | Nov 2011 | US |