Two unit dry stack masonry wall system

A mason wall cementitious building block system comprising two lightweight dry-stackable block units and methods of using such units, including a wall unit and a corner/end unit, connected one to another in an interlocking fashion by means of male posts and female sockets, and variants on each of said units for capping the uppermost course of an assembled wall. The male posts angle rearwardly to define partial apertures, such that adjoining blocks define an aperture which extends vertically between the adjoined blocks for placement of vertical reinforcement, electrical and plumbing chase, and for the introduction of mortar or cement. The top surface defines a recessed cavity for placement of rebar when stacked. The corner/end unit of the present invention interconnects with wall units also by means of posts and sockets and may function as either an end or a corner, requiring only the removal of a small portion of the block at prescored cut lines to alter functions. The wall cap and corner and end caps interconnect with staggered end headers and include partial adjoining apertures to continue vertical apertures formed by lower courses. Methods of assembling walls from the blocks are disclosed.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to unit-shaped masonry blocks, and more
 specifically to dry-stackable masonry unit configurations and methods of
 erecting dry-stackable masonry unit structures.
 2. Description of the Prior Art
 Masonry construction blocks and methods for constructing various kinds of
 brick or block walls are well known in the art. Because of the difficulty
 and high cost of constructing walls of quarried stone or block, cast
 cementitious blocks long ago replaced quarried stone as a preferred
 material in many applications.
 Cast blocks typically have a uniform size and shape, include at least one
 cavity, and frequently permit physical interlocking, either vertically or
 horizontally, with integrally formed or independent connection means. Such
 interlocking designs facilitate rapid assembly and proper alignment during
 fabrication. They also permit assembly without mortar, so that some
 designs of cast blocks may be employed for temporary walls that can be
 easily disassembled.
 Walls constructed of cast blocks may rely exclusively on the mass of the
 blocks to maintain alignment and stability. However, mortarless
 cementitious cast block walls intended for permanent use usually require
 additional stability. Accordingly, many designs permit mortar or
 reinforced concrete to be poured or injected into and to fill gaps and
 aligned vertical and horizontal openings in the blocks.
 However, along with their advantages, the known cast blocks also have many
 disadvantages, including: difficulty in converting the wall units into end
 or corner units; lateral instability; vulnerability of exposed mortar to
 chemical or environmental degradation; expansion and contraction of
 mortar, causing cracking and separation of blocks; difficulty in
 constructing curved configurations; and vulnerability of broad flat
 surfaces to defacement and graffiti.
 SUMMARY OF THE INVENTION
 The present invention is a mason wall cementitious building block system
 comprising two lightweight dry-stackable block units and methods of using
 such units. The blocks include a wall unit and a corner/end unit, and
 corresponding variations on each to function as cap units. Adjoining wall
 units and corner/end units connected one to another in an interlocking
 fashion. Caps for each of these units interconnect with adjoining caps via
 ends of staggered lengths. The unit shapes, the methods of assembling
 walls of such units, and the walls constructed of such units, overcome the
 limitations of the prior art.
 The wall unit of the present invention comprises a front face, a rear face,
 an upper face, a lower face, two sides, two male posts projecting from
 said sides, and two female sockets integrally formed in said sides. In a
 preferred embodiment, two holes extend vertically through the block for
 engagement with raised stops on blocks of inverted position stacked either
 below or above. The male posts angle back from the front face towards the
 rear face and terminate in a rounded enlarged head for interconnection
 with the female socket of an adjoining block. Each rearwardly angled male
 post defines a partial aperture at the side of the block, such that
 interconnected adjoining blocks in an assembled wall define an aperture
 which extends vertically between the adjoined blocks for placement of
 vertical reinforcement rebar, the introduction of mortar or cement, and
 plumbing and electrical chase, as needed. The top face defines a shallow
 recess located in approximately the middle of the block and running the
 length of the block essentially parallel to the front and rear faces.
 The corner/end unit of the present invention comprises an end face, one
 male post, one defined female socket, and a potential female socket
 defined by an interior cylindrical aperture extending vertically through
 the block. This unit may function as either an end or a corner, requiring
 only the removal of a small portion of the block at prescored cut lines
 for use as a corner.
 The wall cap unit comprises outer faces, two sides with a short projection
 extending from and a short recess extending into opposite sides of partial
 arcuate apertures at each side, a bottom surface, and a recess extending
 into the top bed face and running along its entire length generally
 parallel to the outer faces. The upper portion of the outer face is
 decoratively beveled. Corner caps have the same structure as wall caps,
 but with a right angle introduced at the longitudinal midpoint. The end
 cap unit is essentially a truncated wall cap unit with a single partial
 aperture, an end face, and a recess extending into the top bed face that
 terminates short of the interior border of the end face.
 A method of erecting structures comprised of the above-described units
 comprising the steps of:
 1. Forming a poured-in-place concrete footing with embedded vertical
 reinforcement;
 2. Stacking a plurality of courses of block as described above in running
 bond, stepped, or stacked bond layouts with the male posts of blocks
 interconnected with the female sockets of adjoining blocks to align and
 fix the blocks in position and to define a vertical aperture between
 adjoining blocks for placement of the vertical reinforcement and selected
 electrical and plumbing chase;
 4. Laying horizontal rebar in the aperture defined by one course overlying
 another;
 5. Placing a post tension clamp over the vertical rebar until it nests on
 horizontal rebar and tightening the clamp to cut into vertical rebars;
 6. In the case of permanent walls, pouring mortar or concrete into at least
 some of the vertical apertures to flow through said apertures and into
 horizontal apertures to form a continuous joint between adjoining blocks,
 leaving the front and rear faces exposed.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
 The present invention comprises two primary cast block units for
 constructing a dry-stackable masonry wall, and variants on said units for
 capping the uppermost course of an assembled wall. The primary units
 include a wall block unit and a corner/end block unit, and the capping
 units include a wall cap, corner cap, and an end cap. For simplicity the
 same numerals shall be used herein to refer to functionally identical
 elements in each of the various units.
 The drawings show six embodiments of the masonry units of the present
 invention. FIGS. 1, 2 and 4 illustrate embodiments of the wall unit of the
 invention. FIG. 3 illustrates the corner/end unit of the present
 invention. FIGS. 12-18 illustrate the wall cap, corner cap, and end cap of
 the present invention. FIGS. 5-11 and 18-20 show various layouts for
 constructing dry-stackable masonry walls of the invention.
 The masonry units of the present invention may be composed of any number of
 suitable materials, including various polymers, although the preferred
 materials are cementitious.
 1. Wall Unit
 FIG. 1 is a top view of a first embodiment of the dry-stackable cast
 masonry wall unit according to the present invention, and is generally
 illustrated by reference 10. The wall unit according to this first
 preferred embodiment comprises a front face 12, a rear face 14, an upper
 face 16, two male posts 20, and two female sockets 24. A lower face 18
 (not shown in FIG. 1), is shown in FIGS. 6 and 7 in two end views of
 stacked wall units. In the first embodiment, two small diameter holes 28
 extend vertically through the block for engagement with raised stops 30 on
 blocks of reversed position stacked either below or above, and thus
 function to facilitate mating of stacked blocks and to secure the blocks
 in place when positioned.
 The male posts 20 angle back from the front face 12 towards the rear face
 14 at an approximately 133 degree angle and terminate in a enlarged
 cylindrical head 22 for interconnection with the female socket 24 of an
 adjoining block, in the fashion of an anatomical ball and socket joint.
 This interconnection assists in the stacked alignment of the block and
 provides increased lateral stability and resistance to shear forces. The
 rearwardly angled male posts 20 define partial apertures 26, such that
 when adjoining blocks are interconnected a complete aperture 46 is defined
 which extends vertically between the adjoined blocks for electrical and
 plumbing chase, and for placement of vertical reinforcement rebar and the
 introduction of mortar or cement, as is shown in FIG. 5. Additionally, the
 male posts and female sockets are adapted to be rotated slightly with
 respect to one another so as to allow construction of curved walls.
 The top surface defines a shallow recess 32 located in approximately the
 middle of the block and running the length of the block at its middle
 portion essentially parallel to the front and rear faces. When mortar is
 poured into apertures 46 as described above, it also flows horizontally
 along the rebar layout and into recesses 32 between the upper surface 16
 and the lower surface 18 of the block immediately above it.
 FIG. 2 is a top view of an alternative embodiment of a dry-stackable cast
 block wall unit, illustrating a fluted, split face design with a roughly
 finished surface and semicircular concavities 36 in the front and rear
 faces. Any number of forms may be incorporated into the front and rear
 faces to give them an ornamental or decorative appearance in an assembled
 structure. In this second preferred embodiment, a tapered aperture 34
 extends vertically through the block to define a center hole. This
 aperture may be expanded longitudinally according to the size of the block
 and serves a number of functions, including aiding in portability, weight
 reduction in molding, and a cavity for fill or reinforcement in certain
 applications.
 FIG. 4 is a top view of a third preferred embodiment of a dry-stackable
 cast block wall unit, illustrating a fluted split face design especially
 well-suited for sound walls. The block is shown interconnected with
 adjoining blocks in a stacked bond layout with half height alternating
 starter course interlocks course to course. This figure also illustrates
 how the tapered aperture may be expanded in larger variations of the wall
 unit.
 2. Corner/End Unit
 FIG. 3 is a top view of a dry stackable cast block corner/end unit
 according to the present invention. This unit has an end face 38, one male
 post 20, one actually defined female socket 24, and a potential female
 socket defined by an interior cylindrical aperture 44 extending vertically
 through the block. When functioning as an end unit, the unit is left
 intact as depicted, and the open aperture female socket 24 interconnects
 with the male post of an adjoining wall unit block. When functioning as a
 corner unit, a portion of the block is removed by cutting along the cut
 lines 42 through the female socket 24 and the cut line channel 40 to the
 interiorly defined cylindrical aperture 44. When cut in this fashion, the
 cylindrical hole 44 becomes an open aperture of the same shape and size as
 a female socket and thus interconnects with the male post of an adjoining
 block positioned at a substantially right angle to the corner unit.
 3. Wall Cap, End Cap, and Corner Cap Units
 FIGS. 12, 13, and 14, show top, side, and end views, respectively, of a
 dry-stackable cast block wall cap unit of the present invention. This unit
 comprises two outer faces 52, two ends 54, a top bed face 56, two partial
 adjoining apertures 58 at opposite ends of the length of the unit, a
 bottom surface 60, and a recess extending into the top bed face and
 running along its entire length generally parallel to the outer faces. The
 upper portion 68 of the outer face 52 is beveled. The ends are of
 staggered length as defined by a short projection extending longitudinally
 at the side of the partial aperture on its respective end and a
 correspondingly short recess extending longitudinally into the block side
 at the opposite side of the partial aperture, so as to facilitate
 alignment and mating with adjoining wall caps or end caps and to increase
 stability.
 Corner caps, shown only in layout (see FIG. 18), have the same structure as
 wall caps, but with a right angle introduced at the longitudinal midpoint.
 FIGS. 15, 16, and 17, are top, side, and end views, respectively, of the
 end cap unit of the present invention. This unit is essentially a
 truncated wall cap with two outer faces 52, one side 54, a single partial
 aperture 58, an end face 64 with a beveled upper portion 68, and a recess
 extending into the top bed face 56 which terminates short of the interior
 border of the end face.
 5. Method of Constructing Dry-Stackable Masonry Unit Wall
 The blocks of the present invention may be used in a variety of structural
 configurations. Preferably the masonry system is constructed upon a
 standard poured-in-place concrete footing with embedded vertical
 reinforcement, preferably provided at approximately 8 inch to 10 inch on
 center. A level footing and proper placement of reinforcement is achieved
 by using a 2.times.4 or edge at footing height and securing #4 or #5
 rebars to each side of the 2.times.4. Rebar layout is simplified by
 beginning the 8 or 10 inch layout 6 inches in from any end or corner. With
 the footing finished level with the bottom edge of the 2.times.4, the
 footing will provide the necessary straight and level surface to begin
 laying the units. Curved walls may be laid using laminated 1.times.4's and
 the same rebar layout. Alternatively, the first course may be laid without
 poured footings.
 For the standard running bond installation, FIG. 7, the lower course is
 laid by placing blocks adjacent to each other, either end to end or corner
 to corner. Each wall unit is laid with the upper surface 16 down, such
 that the upper surface recess 32 overlays the flat lower surface 18 of the
 block. This requires that the raised stops 28 be chipped from the first
 course only; subsequent courses are alternated such that the raised stops
 28 fit into the through holes 30 of the preceding course.
 For a stacked bond installation, FIG. 6, the first course is laid with the
 upper surface 16 down and the succeeding courses are alternately inverted.
 In the standard running bond installation, alternating layout, FIGS. 5 and
 8, it can be seen that for a given course adjacent blocks interlock via
 male posts 20 and female sockets 24, and thereby form a series of fillable
 vertical apertures or cavities 46 and horizontal apertures or cavities 32
 for the placement of horizontal rebar 48 and vertical rebar 50 and the
 introduction of mortar or concrete. The same cavities and reinforcement
 schedules apply to a stacked bond layout with alternating half-height
 starter, FIGS. 8-9, and stepped layouts, FIGS. 10-11. The running bond
 installation comprises alternating front and rear faces on a given course,
 thus creating alternating recesses located at each rear face 14. This
 produces an attractive wall finish which is an unattractive target for
 defacement by graffiti vandals.
 FIG. 18 is a plan view of the wall cap, corner cap, and end cap layout of
 the present invention, showing horizontal rebar layout 48, vertical rebar
 placement 50, and tension-compression clamp placement 70. FIG. 19 is an
 end view of a running bond layout showing vertical rebar reinforcement 50
 and tension-compression clamp placement 70 in the superior cavity 62 of a
 wall cap as shown in FIGS. 12-14. FIG. 20 is an enlarged view of a
 tension-compression clamp 70 of the kind that may be used to secure the
 superior end of vertical rebar reinforcement 50 in a wall assembly of the
 present invention.
 As can be seen, the cavities created by adjoining partial apertures 58
 complement and continue the same cavities 46 formed by adjoining units
 laid in lower courses. Horizontal rebar is laid over the superior surface
 of the top bed face to complete the last course, and a tension-compression
 clamp 70 is placed over the superior ends of vertical rebar 50 and secured
 at the conjunction with the horizontal rebar. See FIG. 19. Mortar or
 concrete may be poured into the cavities defined by adjoining units to
 flow through the cavities and form a continuous joint around the blocks
 while leaving the front and rear faces exposed and virtually free of
 excess slurry.
 Due to the post and socket fit, spacing between units is adjustable within
 limits. Thus, walls constructed of the blocks of the present invention are
 adaptable to the constraints of terrain. In high walls, areas with a hump
 in the footing may have units spaced as closely together as possible,
 while areas with dips may have units pulled apart as far as possible. This
 will allow the top of the wall to lengthen or shorten as necessary, to a
 maximum of one-half inch per unit.
 Horizontal reinforcement 48 may be installed on any given course of running
 bond. A 3/4 inch dobbie is placed in the center of the wall unit at
 approximately 30 inch intervals and tied to the rebar. The correct
 front-to-back placement will be automatically achieved by the posts of the
 units in the next course. Additionally, proper placement of the vertical
 rebar 50 is secured by the use of a rebar spacer tie which also prevents
 up lift while being vibrated with a mechanical vibrator. While a maximum
 lift of four feet is standard, a lift of two feet will not require
 mechanical vibration and can be consolidated by rodding with a rebar
 dowel.
 End units require no special attention. The post 20 and socket 24 of this
 unit are preferably slightly larger and smaller, respectively, than those
 of the wall unit to assist in proper alignment and to prevent movement
 during mechanical vibrating. Corner units require that one post be cut or
 broken off from a wall unit and two cuts along prescored cut lines 42 of
 the end unit. The corner is then laid in the typical alternating pattern
 for running bonds or stacked in one direction only. Horizontal
 reinforcement is carried through the corner on any given course.
 The masonry system of the present invention is designed to meet the
 specifications required for a coarse grout mix, which may be pumped in
 place and mechanically vibrated or poured in place and rodded by hand with
 a rebar dowel. Clean up of excess slurry from between the units with a
 water hose, nozzle and small trowel should begin as soon as grouting is
 completed.
 While the post and socket design of the present invention allows for
 considerable flexibility in construction tolerances and techniques, they
 are equalled by the variable possibilities for architectural design with
 only a few finishes or colors. For example, quoins may be highlighted at
 corners and ends by simply changing the colors. The apparent depth of the
 recess may be dramatized or negated with a similar change of color.
 On large walls of any height or length, a half-height block unit may be
 employed for more cost-effective construction and a more architecturally
 pleasing finish. For smaller scale projects a proportionately smaller
 version may be desirable. While of the same design, it would have a rebar
 layout of approximately 8 inch on center for added structural integrity,
 but would also have the appearance of delicately interwoven brick work.
 The masonry system of the present invention is inherently flexible and
 versatile with a minimum of bearing cross section. It may be employed for
 either free standing or retaining walls. It may be either straight or
 curved vertical or stepped, and laid out in running or stacked bonds. Its
 unique design minimizes manufacturer materials, on-site labor, and skill
 requirements for construction. It is self-aligning, eliminates vertical
 gaps, follows minor footing contours, provides bond beam on any course,
 improves sound attenuation, allows continuous reinforcement, improves
 design, and discourages graffiti.
 While this invention has been described in connection with preferred
 embodiments thereof, it is obvious that modifications and changes therein
 may be made by those skilled in the art to which it pertains without
 departing from the spirit and scope of the invention. Accordingly, the
 scope of this invention is to be limited only by the appended claims.