Patent Application
20110258957
Not applicable.
This invention generally relates to masonry materials, particularly masonry units for constructing multi-wythe walls.
Masonry units (e.g., clay or concrete bricks or blocks) have been used for many years in the construction of building walls. To form a wall, multiple masonry units are typically stacked vertically with cementitious mortar materials placed between them in order to permanently bind the units together. In many cases, the masonry units are stacked in a single-wythe structure (i.e., a structure having a width of one masonry unit). While single-wythe walls are popular and relatively easy to construct, increasingly demanding building codes now require wall systems with greater structural integrity, increased thermal resistance, and improved moisture control.
These requirements have proven difficult to meet, both physically and economically, using single-wythe wall designs. Consequently, the industry has begun to utilize multi-wythe masonry wall systems and cavity wall systems. These systems allow for steel reinforcement within the wall, greater levels of thermal insulation, and air spaces that allow intrusive moisture to be controlled and channeled out of the wall to the building's exterior.
Such wall systems typically include two or more separately-constructed walls that together form the composite wall. Such composite walls are typically constructed by first building a concrete masonry wall, applying a layer of insulating material to the exterior surface of the masonry wall, and then building a second wall (sometimes called a veneer wall) that is spaced from the first wall. The two masonry walls are typically mechanically tied together with metal wires or tabs placed in the horizontal mortar joints of both walls. An air space may be left between the insulation of the first wall and the second wall to define a cavity wall or a rain screen wall that permits the ventilation of air between the two walls. The wall system may also be reinforced with vertical steel rods running through the cores of the masonry units, horizontal steel rods, and/or horizontal ladder wires.
The construction of a composite wall of this type is typically time consuming and labor intensive. Because the two walls are build sequentially, the construction of the veneer wall depends on the completion on the concrete masonry wall. Moreover, when vertical steel reinforcement rods are utilized during construction, masons must typically lift the heavy masonry units to thread their cavities over the top of fixed vertical rods. Because vertical rods are typically four to eight feet in length, this task can be very strenuous.
Hence, there is a need for an improved masonry unit that facilitates construction of a multi-wythe wall.
In one aspect, the present invention provides a masonry unit for constructing a wall. The masonry unit comprises at least three substantially vertical parallel partitions extending along a lengthwise direction. Each of the partitions connects to an adjacent partition by a web extending in a widthwise direction, thereby defining a pair of oppositely-facing open-ended recesses on either side of the web. Each of the webs connecting the partitions is offset in a lengthwise direction from any adjacent webs in the masonry unit. When a wall is formed from a plurality of the masonry units by positioning multiple rows of stacked masonry units on top of each other in a horizontally offset and vertically inverted manner, a plurality of separated continuous vertical cavities extending through the multiple rows are formed within the wall.
In some forms, the masonry unit may further include a vertically-extending support formed along one at least one of the partitions to provide support for the partition during fabrication of the masonry unit. The vertically-extending support may be aligned with one of the webs in the lengthwise direction. If mortar is applied to the top surface and bonds the unit to the unit above, the vertically-extending support may further lend additional load-bearing capacity to the overall wall system.
In some forms, the masonry units may be configured such that, if a second row of masonry units is stacked on top of a first row of masonry units in a vertically inverted manner and are horizontally offset approximately one-half of an overall length of the masonry unit from the first row, then the webs of the masonry units in the first row and the second row are vertically aligned with one another. Each of the webs may be offset from any adjacent webs in the lengthwise direction of the masonry unit by substantially one half of an overall length of the masonry unit. Moreover, each of the webs may be offset from ends of the partitions in the lengthwise direction of the masonry unit by substantially one quarter of an overall length of the masonry unit. Because some mortar may be inserted between the blocks, the one-half and one-quarter offsets may be approximate.
In some forms, at least one web may include a vertically facing open-ended slot configured to receive a horizontal reinforcement rod.
In some forms, the partitions and the webs may comprise cement and each of the partitions may integrally connect to the adjacent partitions by the webs.
In some forms, the masonry unit is generally rectangular shaped. In this way, when a wall is formed, these masonry units may maintain an aesthetic consistent with conventional masonry units and, moreover, may be made to easily interface with standard corners, end pieces, and other fittings.
A masonry unit of this type offers many advantages over conventional concrete masonry units with closed cavities. With the improved masonry unit, a wall can be constructed with multiple layers in manner that is far easier than the construction of a conventional composite wall. Whereas conventional composite walls require the sequential building of at least two walls with a space there between, by using the disclosed masonry unit the same effect can be achieved with the construction of a single wall. Moreover, because the masonry unit has open-sided cores, the masonry units do not need to be lifted over the top of vertical reinforcement rods during construction. This reduces the amount of lifting necessary to build the wall and eliminates the amount of reinforcement rod material required (as longer continuous lengths of reinforcement material can be utilized).
The masonry units can be used to form a wall with separated continuous vertical cavities. Some of these cavities can serve as a rain screen wall to control moisture and/or provide ventilation to avoid mold and maintain healthy building structures. Additionally, these cavities can receive insulation, receive reinforcement materials to strengthen the wall, and/or house utilities such as plumbing lines, electrical cables, and so forth.
Additionally, this single wall has superior thermal and acoustic transmission properties that are not found in walls constructed with masonry units in which the webs directly connect a front and rear face of the wall.
The foregoing and advantages of the invention will appear in the detailed description which follows. In the description, reference is made to the accompanying drawings which illustrate a preferred embodiment of the invention.
The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
Referring generally to the figures, a masonry unit according to the present invention facilitates improved construction of a wall compared to previous masonry unit designs. Masonry units according to the present invention, when constructed to form a single wall, provide properties and advantages of a multi-wythe and/or a cavity-wall system. In the following paragraphs, the structure of masonry units according to the present invention are first described. Thereafter, walls made from masonry units according to the present invention are described in further detail.
Referring first to
The connecting webs 14a and 14b are spaced from horizontally-facing ends 16a, 16b, and 16c of the partitions 12a, 12b, and 12c to define, together with the partitions 12a, 12b, and 12c, oppositely facing recesses 18a, 18b, 20a, and 20b on the ends of the masonry unit 10. These recesses 18a, 18b, 20a, and 20b are generally U-shaped, extend inwardly from the horizontally-facing ends 16a, 16b, and 16c, and are the fully height of the masonry unit 10. During the construction of a wall, these side-accessible recesses or open-sided cores permit the masonry unit 10 to be moved horizontally relative to a vertical reinforcement rod to receive the rod in one of the recesses 18a and 18b. This feature significantly reduces the amount of lifting required for constructing a wall using masonry units 10 compared to traditional masonry units with cavities/cores that are centrally disposed in the masonry unit and which are closed except on the top and bottom faces of the masonry unit.
In addition to the benefit of reduced labor during construction, this open-sided core design also allows for the use of longer vertical supports because overhead lifting is not required. This means that overlaps, ties and couplers do not need to be used to join separate shorter vertical supports and reduces the amount of vertical support material needed.
To accommodate the formation of separated continuous vertical cavities in a wall constructed from the masonry units 10 in which adjacent rows of masonry units 10 are offset by one-half length, the webs 14a and 14b are preferably spaced apart from each other in a length direction of the masonry unit 10 by about one-half of the overall length of the partitions 12a, 12b, and 12c. The webs 14a and 14b are also preferably spaced apart from the horizontally-facing ends 16a, 16b, and 16c of the partitions 12a, 12b, and 12c by about one-quarter of the overall length of the partitions 12a, 12b, and 12c. To account for the mortar between the units, the distance between the webs 14a and 14b may be slightly greater than one-half of the length of unit 10 and the distance from the webs 14a and 14b to the nearest ends 16a, 16b, and 16c may be slightly less than one-quarter length. Such dimensions provide a well-balanced structure about both horizontal axes, which facilitates ease of handling and installation. Such dimensions also provide additional advantages when constructing a wall using multiple masonry units 10 as described in further detail below.
In addition to the partitions 12a, 12b, and 12c and the webs 14a and 14b, the masonry unit 10 further includes vertically-extending supports 21a and 21b that integrally connect to and are disposed on the first and third partitions 12a and 12c, respectively. These supports 21a and 21b are positioned along the inwardly facing side of the partitions 12a and 12c in the recesses 18a and 18b in a region in which the partitions 12a and 12c are largely otherwise unsupported (i.e., not disposed near the webs 14a and 14b). The supports 21a and 21b provide support for the first and third partitions 12a and 12c, respectively, when initially fabricating the masonry unit 10. Further, in a wall formed from the masonry units the supports 21a and 21b may be respectively aligned with the first and second webs 14a and 14b in such a manner that the supports 21a and 21b may also be vertically aligned with one another when the units 10 are stacked.
The interfaces or corners between the partitions 12a, 12b, and 12c, webs 14a and 14b, and supports 21a and 21b are preferably curved or radiused to reduce stress concentrations and cracking at the interfaces. In some embodiments, such as the embodiment depicted in
Referring now to
In addition to the preferred dimensions and features described above, a masonry unit according to the present invention may have various heights. For example, the masonry units shown in
Turning to
Next, and as depicted in
Positioning the masonry units 410 in the lower and upper rows 30 and 32 in the above manner provides several advantages. For example, the webs 14 of the upper row 32 are stacked vertically upon one of the webs 14 of the lower row 32. As such, the webs 14 define a plurality of separated continuous vertical cavities 36 (
As used herein, the term “continuous” and variations thereof, when used to describe the vertical cavities 36, mean that the shape of the cavities 36 is generally constant as viewed from above as the webs 14 align with one another. It will be appreciated that some limited amount of discontinuity may occur at the interfaces between the masonry units 410 or where other features have been intentionally introduced (e.g., as described below, the vertically facing open-ended slots 42 configured to receive horizontal reinforcement rods 44 which may interrupt the continuity of the wall of the cavity).
Because of the separation of the cavities 36, grout and/or insulation, etc. is prevented from leaking horizontally into other cavities where it is not desired. Similarly, the separation facilitates vertical drainage of intrusive moisture because it has a clear, uninterrupted path downward. There are no webs obstructing the flow as is found with conventional masonry units.
The separated continuous vertical cavities 36 may provide vertical compartmentalization that inhibits horizontal air movement within the wall 25 (i.e., air movement between different cavities 36). When combined with well-known ventilation components (not shown) at the top and bottom of the wall 25, the vertical cavities 36 also facilitate natural convective airflow that may effectively act as a rain screen wall. Additionally, any moisture that passes through the outermost partition 12c of the masonry unit 410 or through voids in the mortar joints drains down the interior of the vertical cavities 36 and out through weep holes (not shown) at the bottom of the wall 25. In this way, wind-driven moisture is controlled and channeled out of the wall 25 to reduce the potential for moisture-induced problems.
In addition, the serpentine transmission paths through the wall 25 defined by the horizontally offset webs 14 provide thermal and acoustic advantages. In particular, the serpentine paths define relatively long thermal and acoustic paths connecting the interior and exterior of the wall 25 compared to walls constructed using traditional masonry units with single webs that directly connect the front and back walls of the masonry unit. Assuming the material of the masonry unit to be the path of least resistance for sound or heat, the distance through the wall is a length approximately equal to the thickness of the wall plus the lengthwise distance between the webs 14. Such a long thermal path significantly reduces the rate at which heat may be conducted through the wall 25 and, similarly, the long acoustic path significantly reduces sound transmission through the wall 25.
Additionally, the wall 25 advantageously provides additional thermal mass to the temperature stability of a building interior. Thermal mass can also reduce the need for supplemental heat in cold environments when included as part of an overall passive solar heating design.
Moreover, as best seen in
Referring now to
As another example and referring to
As yet another example and referring now to
A wall formed by masonry units according to the present invention may alternatively have other types of horizontal reinforcements. For example and referring to
Walls formed by masonry units according to the present invention may include combinations of the above components and materials. For example and referring to
Referring to
Masonry units and walls constructed therefrom according to the present invention may further vary from those described above. For example, conventional masonry fittings can be used in conjunction with the masonry units. In particular, corner units, closed end units, bond beams, and the like can be utilized with the masonry units in a wall structure. As another example, the separated continuous vertical cavities 36 may additionally or alternatively house components such as plumbing lines, electrical wiring, and data/communication cables.
Materials used to manufacture the invention are typically sand, stone, Portland cement, and water. Cementitious substitutes such as flyash, ground granulated blast furnace slag, cement kiln dust, silica flour and silica fume may alternatively be used. Iron oxides may be used to provide color, and admixtures may be used to aid in manufacturing or provide or enhance certain properties of the masonry units.
Masonry units according to the present invention may be manufactured using a concrete block machine such those manufactured by Besser Co., Columbia Machine, Tiger, or the like, using a concrete paver machine such those manufactured by Columbia Machine, Tiger, Masa, Hess, or the like, or using other similar machines. The masonry units may also be manufactured using a wetcast process in which concrete with a measurable slump is placed into a mold and consolidated prior to curing. As described briefly above, the vertically upright supports 21a and 21b connected to the partitions 12a and 12c, respectively, provide support for the partitions 12a and 12c during fabrication and subsequent transport of the masonry unit.
When the masonry units are manufactured using a block or paver machine, the forming mold can be fabricated in various manners. The complete mold consists of two main assemblies: the mold and the head.
One mold design is consistent with traditional block molds. This design utilizes metal wear partitions of various shapes and dimensions, made of hardened material, that are bolted into position in a rigid metal frame to create the mold.
Another mold design is consistent with traditional paver molds. This design utilizes a one-piece hardened-metal insert that is bolted into the mold. The insert is typically formed from a piece of steel or other wear-resistant material from which material is removed to form cavities of various shapes. These cavities define the shape of the mold. The head assembly consists of a top partition, plungers, and shoes. The various parts can be welded or bolted together.
It should be appreciated that while masonry units have been shown with three parallel partitions and two webs that can be used to form a wall having two rows of separated continuous vertical cavities therein, that masonry units having more than two rows of separated continuous vertical cavities can be made by adding additional partitions and webs. For example, three rows of separated continuous vertical cavities might be formed using a masonry unit having four partitions with three webs. In this instance, the two outermost webs may be co-planar with one another such that the first and third rows have aligned vertical cavities.
From the above description, it should be apparent that the masonry units and walls constructed therefrom according to the present invention provide various advantages over traditional masonry units and walls. In particular, the masonry units facilitate faster and easier construction of masonry walls with vertical reinforcement versus traditional masonry walls with vertical reinforcement. The labor associated with construction of a wall using masonry units according to the present invention is estimated to be less than half of that required for traditional multi-wythe walls. As such, the masonry units provide construction cost advantages through material, time, and labor savings.
Similarly, the masonry units and walls constructed therefrom also perform the functions of traditional multi-wythe walls. In particular, the masonry units provide multiple columns of separated continuous vertical cavities that can be utilized for placement of reinforcing materials, insulation, moisture control mechanisms, plumbing, electrical wiring, ventilation, data/communication cables, and the like.
Preferred embodiments of the invention have been described in considerable detail. Many modifications and variations to the preferred embodiments will be apparent to a person of ordinary skill in the art. Therefore, the invention should not be limited to the embodiments described, but should be defined by the claims that follow.
This application claims the benefit of U.S. Provisional Patent Application No. 61/326,346 filed Apr. 21, 2010, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61326346 | Apr 2010 | US |
