The present invention relates to stack concrete masonry systems for building structural load bearing and non-load bearing walls and, more particularly, to a system and method that utilizes precision grinding of pads on a top portion of masonry blocks in addition to a mechanical system and method for high-speed, precision application of a masonry adhesive or mortar/grout. The ground leveling pads “self-level” the masonry blocks to provide for accurate and simplified assembly of concrete masonry while the applied mortar/adhesive serves to both adhere the blocks together and serves as a high speed, building code approved mortar/grout between horizontal and vertical surfaces of adjacent blocks.
Present masonry construction techniques provide for essentially two masonry construction techniques: the traditional mortared block technique where mortar is placed between each block both on a horizontal face as well as a vertical face; and a newer technique of dry stacking where blocks are designed to be simply placed one upon the other in some arrangement without any mortar between the blocks themselves. An advantage of dry stack masonry systems is that the labor component of installation can be dramatically reduced. Some studies have shown that dry stack masonry systems are up to ten times faster to install than conventional joint mortared masonry systems and require a significantly less skilled labor force to install them. Because these systems do not use bonding mortar to provide joint support, it may be necessary to use other means of developing wall strength to meet various building codes which limits its usefulness.
For example, various building codes may require dry-stacked concrete block cells to be fully filled withconcrete grout in order to provide specified structural integrity. Some applications may require all the cells to be filled with concrete. Other applications may require the concrete to be poured into distinct vertical columns and only in certain cells or cores of the block. These applications may require cells, for example, to be filled generally at four foot on center increments and/or at wall corners and jambs of windows and doors or various load points. A general overview of the use of current dry stack methods in masonry wall construction can be found in National Concrete Masonry Association's (NCMA) technical publication TEK 14-22 “Design and Construction of Dry-Stack Masonry Walls” Incorporated herein by reference.
Currently, the accepted practice for constructing with concrete masonry units using the traditional mortared technique (structural concrete block) requires that the blocks be mortared together with a code approved masonry mortar mix. Typical masonry mortar mixes contain portland cement, lime and mason sand, as well as additives for improving workability. These masonry mortar mixes are applied and installed by an experienced mason using a trowel. The trowel has been used in constructing masonry walls for centuries, without much of any change in design. As a result, the availability of a skilled mason applying mortar with a trowel becomes the limiting factor in the how fast a masonry wall can be constructed. Masonry up to now had been very skilled and labor intensive. The amount of labor cost to install a masonry wall is currently in the range of 66% to 75% of the overall masonry construction costs.
There have been attempts to change the dynamics of the masonry construction market in an attempt to lower the labor expenses associated with typical block concrete construction. As a result, many systems have attempted to eliminate the need for mortar during construction of the wall. The dry-stack masonry wall describe above is one such example. By eliminating the mortar step, the installer should be able to go much faster in erecting walls. The issue with current mortar-less systems, however, is that these systems do not have sufficient height control to duplicate the height control capability of a mortar joint between block that can be adjusted to take care of standard concrete masonry units block height irregularities. The mortar, besides providing bonding and sealing, also serves as a leveling mix that provides a way for the wall builder to adjust the height and level of the courses to meet the specific dimensions for openings and top of wall elevations. Moreover, dry stack masonry walls may not have the same load/shear strength as traditional mortared masonry walls and many building codes recognize this and are reluctant to change to allow dry-stack masonry walls in many applications. Drystacked concrete masonry walls generally must be reinforced and/or grouted. Over half the market for masonry is “un-reinforced”.
Given that construction codes and the previous personal experiences of contractors, building inspectors and masons generally encourages or requires mortared concrete walls, a system that includes a thin mortar and grout along with a system and method to apply such thin joint mortar developed to meet or exceed the requirements of the Masonry Standard for Unit Mortared Masonry ASTM-C270 Type S/M) for use with precision ground masonry blocks is required. Mortar application techniques should be designed to eliminate the need to use a mason's hand trowel to apply mortar to masonry blocks. All non-trowel, conventional ways of applying mortar using (1) a standard grout bag (baker's bag) for small project applications and (2) a high speed mortar pump system for large project commercial-style applications are too slow or too messy or both. Traditional mortared masonry has been installed with the aid of a mason's hand trowel. Much skill and effort is required to effectively apply mortar to masonry structures with a trowel. The disclosed precision ground masonry block along with the disclosed easy flow mortar eliminates the need for skilled masons and reduces mortar volume on a project by up to 90%, making it highly effective and efficient. But such easy flow Flow mortar must be applied using a fast and effective way to make it outperform traditional trowel applied installations. Using just a grout bag is too slow while using a mortar pumping device with simple nozzles can be too messy and requires significant level of skill.
Accordingly, a need has existed for a system and method that provides a self-leveling masonry block (the block does not rely of the mortar to level or control the height of the block) having one or more predetermined areas (that are smaller than full top surface area of the masonry block) that can be ground down to a precise level to ensure that there will be no “rocking” or un-levelness in the stacked blocks and that are installed using a non-hand trowel applied mortar/grout or adhesive which serves to adhere the blocks together without the need to use skilled masons using hand trowels and large amounts of conventional mortar (much of which is wasted or classified as “trash” Also needed are special tools and methods that may be attached to traditional grout bags and/or mortar pumping systems such that the mortar may be applied between the masonry blocks or on the face of the blocks (as grout between the blocks, or both) that is fast, easy to use, clean and effective and that requires little or no skill to use and apply.
In order to solve the problems associated with conventional mortared masonry and with the mortar less/dry-stacked methods of building masonry walls, a new system was developed. This novel system combines a wet-stacking installation method (applying mortar/grout between the blocks as they are being installed—versus dry stacking which is simply stacking the concrete blocks with no mortar/adhesive or grout between the blocks as they are being installed) with self-leveling and precision ground concrete building blocks. This system eliminates the need for hand trowel-applied mortar. The system dramatically reduces the need for highly skilled masons in the overall construction crew, while also providing nearly the speed of conventional dry-stack methods and systems.
In one aspect the invention features a method of producing a stackable building block for constructing a masonry wall. The method comprises the acts of molding a concrete block having a front section coupled to and substantially parallel with a rear section. Each front and rear sections has a bottom surface and a top surface, wherein the top surface on both the front and rear sections includes at least a central region having a height which is greater than the first and second end regions located on either side of the central region. The method also includes grinding the central region of the top surface of the front and rear block sections to a predetermined height.
The method of producing a stackable building block for constructing a masonry wall utilizes a building block that is a dry stackable concrete block. Alternatively, the method of producing a stackable building block with mortar/grout/adhesive for constructing a masonry wall utilizes a building block that is a wet stackable concrete block.
In another aspect of the invention, the method of producing a stackable building block for constructing a masonry wall includes at least a front surface having a sloping edge region for accepting mortar/adhesive and forming an area into which mortar/adhesive can flow and be worked to for a traditional looking mortared joint.
In a further embodiment of the invention, the method of producing a stacked building block wall utilizing the stackable building block further comprises applying a flowable, thin set mortar onto the top surface of the stackable building block using a high-speed applicator. The high-speed application may be a grout bag or grout pump. The mortar is applied to a minimum thickness of typically ⅛ of an inch or less.
In another embodiment of the invention, the grinding of the higher surface of the top surface is precision ground to provide a stack building block of a specific precision height (typically 8″ in the USA)
In an additional embodiment of the invention, the central region of the top surface further may include a plurality of indents or serrations or channels. The method of producing a stacked building block wall utilizing the stackable building block further comprises the acts of applying a bead/slug of a special flowable, thin set mortar/grout/adhesive onto the top surface of the stackable building block using a high speed applicator and allowing the mortar/grout/adhesive to enter the plurality of indents or serrations or channels on the central region of the top surface, wherein the addition of the mortar does not significantly increase the specific precision height of the stackable building block as installed. Next, the method comprises stacking a second duplicate stack block staged halfway off-center from the first block and stacking a third duplicate stack block staged halfway off-center in a direction opposite and adjacent to the second stack block.
In a further aspect of the invention, the stack building block has a chamfered or beveled edge on one more exterior edges of the building block.
It is important to note that the present invention is not intended to be limited to a system or method which must satisfy one or more of any stated objects or features of the invention. It is also important to note that the present invention is not limited to the preferred, exemplary, or primary embodiment(s) described herein. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention which is not to be limited except by the allowed claims and their legal equivalents.
These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein:
The present invention features a masonry block system and method providing masonry blocks having top surface regions that self-level the blocks without the use of mortar or adhesive and to an adhesive/grout/mortar formulation and application system that allows for a generally non-skilled work to quickly apply a limited amount of adhesive to a masonry block and to, in one embodiment, simultaneously grout the masonry joint, as will be explained in further detail below. As used herein, the terms grout or adhesive or mortar are used interchangeably.
Referring to
According to an exemplary embodiment of the invention, the top surface 1109 may be divided into regions of varying levels during the molding process. The stretcher unit 1102 may be molded with a central region 1111 having a slightly higher or raised surface 1500/1502 than the adjacent top surfaces 1113 which have a lower profile by approximately ⅛ inch. Additional regions of the block such as end regions and the like may also include and benefit from such raised surfaces that are also ultimately ground to a precision height. After the molding process, the top of the raised surface 1500/1502 which may be in the range of approximately 2″ to 7″ in length (and preferably only about 3″ in length) are ground to provide a more accurate, precision height of the stretcher unit 1102.
The lower surface areas 1113 are molded at a height slightly below the ultimate desired height of the stretcher unit 1102, while the higher surface region 1500/1502 in the central part 1111 of the block front and rear sections are molded slightly higher than the desired height of the stretcher unit 1102. Since masonry blocks are typically made from a mixture of concrete, sand and small stones, the ultimate height and “levelness” of each block can and does vary, particularly because of the effects of the small stones which may protrude upwards from the concrete block. In the prior art, this variation in height was taken care of by the application of a fairly thick layer of mortar, applied by a skilled mason using a hand trowel, all of which is eliminated by the present invention.
During the grinding process, these height irregularities are eliminated. The grinder will either not or perhaps barely grind the lower surface 1113 due to the height being just shy of the set grinding height. As the higher surface pads 1502/1500 passes under the grinder, the grinder removes a portion of the concrete block unit material that exceeds the desired height providing a more accurate stretcher unit 1102 height in view of the molded height. By reducing the amount (length) of the stretcher unit 1102 to be ground down (i.e. a rather short 3″ or so central region 1111 and any potential raised height end regions), there is improved grinding performance resulting from an increase in the throughput speed as well as reduced wear on the grinding heads.
For example, when manufacturing an eight-inch high unit, the block may be molded with lower surface 1113 being a one-sixteenth ( 1/16) of an inch shy of eight inches and the higher surface(s) 1500/1502 being a one-sixteenth ( 1/16) of an inch above eight inches. During the grinding process, the grinder may remove portions of the higher surface 1500/1502 providing a height that is eight (8) inches to a greater degree of 1/64″ or less of an inch accuracy. This accuracy allows for good overall height control of the wall and levelness (since blocks in the next row above will touch two (2) or more raised and ground regions 1500/1502 on two (2) blocks in the row or course underneath the present block) without the block “rocking” which is normally not a problem in a mortared wall since the mortar takes up any unevenness in the blocks.
The precision ground block units provide for precision height control even when mortared together. The design provides for lower surfaces 1113 and a higher surface 1500/1502, which reduces the amount of influence the mortar has on adding height to the courses of the wall. The higher surface 1500/1502 may further have an appropriate number of indentations (grooves or channels) that serve to reduce the mortar influence in height control to almost zero by providing channels or grooves into which any adhesive, grout or thin mortar placed on the higher surface may flow. Any grout, adhesive or this mortar in the grooves or indentations will still serve to adhere the top surface of this block with the bottom region of a block placed on top of the block. This higher surface 1500/1502 is then ground to the desired height to provide units of precision height. The geometry of the higher 1500/1502 and lower 1109 surfaces and the indents in the top surface 1109 are designed in such a way as to provide a self-leveling aspect to the wall construction. The self-leveling feature allows for high stacking productivity even if the field conditions are not perfect. The self-leveling provides for a near foolproof solution that allows the construction of the concrete block wall to be more forgiving.
As an example, if foreign materials are present in one level of the stacking, as subsequent courses are stacked, there is little or no potential for “rocking” of a block. The precision ground region of the higher surface 1500/1502 located in the top surface 1111 of the block's face will implement the self-leveling feature and allow for an instant remedy to blocks that would otherwise by crooked or at an angle. The problem of angled or crooked blocks can be remedied immediately without the need for shims or grinding.
The surface-grinding embodiment described above is not limited to the lower surface 1109 being lower than the desired height. The lower surface 1109 may be molded to the exact height of the desired stretcher unit 1102. In this example, additional grinding may be required with the bulk of the grinding occurring on the higher surface 1500/1502. Additionally, the surface-grinding embodiment may have different lengths of higher surfaces 1500/1502 and lower surfaces 1109. In one embodiment, each surface is roughly divided into thirds; however, the invention if not limited to this exemplary width and ratio. The higher surface 1500/1502 may be greater or less than a third of the overall length of the cement block. In addition to grinding certain predetermined regions of the front and rear top portion of the blocks, certain end portion, such as end portion 1315 may also be ground to assist in providing a wall construction of uniform height.
After manufacturing and precision grinding of the stretcher units 1102, the stretcher units 1102 may be assembled as previously discussed herein. In the preferred embodiment of the method of the present invention, an adhesive (also termed grout or thin mortar) is applied between each course of the stretcher units 1102. The adhesive may be squeezed out from the areas between the higher surface 1500/1502 and the bottom of the next course of units. Preferably, the adhesive may be applied on the top surface 1109 of the stretcher unit 1102 that does not have any raised area 1500/1502. In this manner, the adhesive has no impact on the height of the block wall. The height is controlled solely by the precision ground areas. The adhesive preferably remains in areas between the lower surface 1109 and the bottom of the next course of stretcher block units 1102 placed on top of the current block. Once the adhesive cures, the adhesive may provide additional load bearing support that typically meets or exceeds code specifications. The adhesive may be an expandable adhesive to aid in the filling of voids between surfaces. The adhesive in this case is selected to provide a desired expansion force that prevents movement of the stretcher unit 1102 after proper positioning while expanding to fill any voids or spaces between surfaces of blocks 1102 stacked one on top of the other.
An exemplary code compliant mortar/grout/adhesive according to one feature of the present invention was designed and developed to be applied without a trowel but rather, using a high-speed applicator as will be explained further below. Examples of such a high-speed applicator include a grout bag or a grout pump well known in the industry for applying grout to tiles/brick (tuckpointing) or to the exterior face of previously erected block walls. The stackable block design of the present invention allows for the mortar/adhesive disclosed herein to be easily squeezed between the subsequent blocks to a thickness of typically less than ⅛ of an inch so that the mortar is not dictating the height of the wall. Rather, the height of the wall is dictated by the high-speed grinding height gauging process that each block passes through to make it a precision height unit with tolerances that are an order of magnitude better than in the ASTM C-90 block standard (less than 1/64″ compared to the +/−⅛″ standard). Fine grained thin set mortar readily available in general home building supply stores like that used for laying tile on floors or walls will work well with the present invention as the mortar/adhesive.
A mortar/adhesive may also be provided that has properties that conform to the Masonry Standard for Unit Mortared Masonry (in the USA—ASTM C-270) but is also designed so that it can be applied at high speeds without a trowel or experienced applicator and applied so that it does not interfere with the height control aspects of the precision block of the invention. Such a code approved mortar can be applied at a thickness as thin as 1/64 of an inch. The mortar is ultra fine grained and made with cements, aggregates and chemical modifiers as in the thin set motors described above that give it its unique properties. The particles in the mortar are typically less than 5/1000 of an inch. The mortar should have good water retention and should not dry out through evaporation or through suction from the dry block to which it is applied. The water retention of the mortar allows the mortar to remain flowable after application to the block allowing all unnecessary mortar to flow or squeeze out from between two blocks. If the mortar where to lose its ability to flow, the mortar would add too much thickness between the blocks and would affect the ability of the wall to be built to meet specified elevations.
Multiple levels may be provided on the top surface 1109 of a stretcher unit 1102. According to a second exemplary edge-grinding embodiment, the top surface 1109 may be divided into regions of varying levels during the molding process. The stretcher unit 1202 may be molded with a curved top surface 1209 that has a higher surface 1211 sloping down to the adjacent top lower surfaces 1213. After the molding process the top surface 1202 may be ground to provide a more accurate height of the stretcher unit 1202 as previously described with regard to the embodiments in
Referring to
The present invention features a block and method which allows for fine height control and adjustment by quickly and easily changing the location where the installer positions a bead of mortar on the bed joint of the block. The combination of the location or placement of raised pads 1500,
The blocks according to the present invention may include both a raised pad area 1500,
Cement blocks manufactured and erected into a wall, according to the teachings of the present invention, may not have mortar or adhesive between the vertical joints of adjacent blocks, as commonly done in the prior art and may or may not have any visible mortar between the adjacent blocks horizontally. Such mortar is not necessary structurally using the block and methods taught by the present invention. However,
By controlling the location of where a bead/slug of adhesive/mortar 1520
Accordingly, the installer is able to quickly add fine height elevation control to the finished wall by simply changing the location of where a bead of mortar/adhesive is applied. This allows a user installing the blocks constructed according to the teachings of the present invention and using the methods disclosed herein, to handle any height elevation issues in the field and brought on by footer or base course issues, blocks being too wet or dry, too lightweight, normal or heavyweight, all without shims or other more costly and time consuming remedies.
The raised leveling pads of the present invention are designed to be run through a grinder to provide precision height control during assembly and construction of the finished wall. The pads are also designed to be wide or long enough, for example approximately 5.5 inches, to allow for blocks to be stacked directly one on top of another in a “stacked bonded” fashion without rocking. The pads may also be designed with channels to accommodate brick tieback anchors and to aid in the flow of the precision mortar to maintain precision height control when stacking using mortar (wet stacking).
The raised leveling pads of the present invention are also designed to be wide or long enough to allow for blocks to be stacked “offset” to one another in a “running bond” fashion without rocking.
In addition, as previously mentioned, the raised leveling pads of the present invention may also include one or more channels that facilitate the use of brick tiebacks. The channels may be full channels extending completely through the raised areas to accommodate the brick tie backs or other reinforcement wire, or partial channels extending halfway or quarter way through the raised area to provide relief areas for the precision, fine grain mortar to flow away from the top of the leveling pads to ensure that the block height during construction is maintained. Under normal circumstances, mortar is not normally applied to the top of the leveling pads but in front of them. However, in the event the height of the block needs to be increased during construction, the precision mortar may be applied either on top of or in close proximity to the leveling pads providing a “liquid shim” for the wall system.
Another feature of the present invention is a block, in accordance with the teachings of one embodiment of the present invention, that includes at least one side region 2000,
One additional feature of the present invention are novel tools that are designed (1) to fit onto a conventional grout bag and (2) onto a conventional mortar pumping system, to provide for an easy, fast, clean, and effective way to place the mortar/adhesive described above in which has not been available in the prior art.
The mortar pump tool of the preferred embodiment of the present invention features twin tips 2052a and 2052b,
When tested, the mortar/adhesive disclosed and described herein was mixed and placed into both the grout bag and the mortar pump system. Both tools allowed for a quick and easy application of mortar, whether it was injected into the pre-stacked block with a grout bag or pumped onto the block to provide an ideal bead of mortar at both bed and head joints of the Block. The mortar/adhesive joints were installed without a trowel; easily, quickly, cleanly, and with excellent coverage (typically less than 1 lb. of mortar per block compared to the conventional 5 plus lbs. per block).
Accordingly, essentially anyone (unskilled labor) can construct masonry block walls with the described precision ground masonry block and the mortar/adhesive that is fast, easy and clean; all done effectively without a mason's trowel.
Modifications may be made to fit particular operating requirements and environments as will be apparent to those skilled in the art, the invention is not considered limited to the examples chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention which is not to be limited except by the allowed claims and their legal equivalents.
This application is a continuation of U.S. patent application Ser. No. 12/466,972 filed on May 15, 2009 entitled “SYSTEM AND METHOD FOR PRECISION GRINDING AND SELF-LEVELING INSTALLATION OF CONCRETE MASONRY SYSTEMS”. The present application also claims priority to: U.S. Provisional Patent Application 61/230,358 filed on Jul. 31, 2009 entitled “SYSTEM AND METHOD FOR PRECISION GRINDING AND SELF-LEVELING INSTALLATION OF CONCRETE MASONRY SYSTEMS”; U.S. Provisional Patent Application 61/249,619 filed on Oct. 8, 2009 entitled “SYSTEM AND METHOD FOR PRECISION GRINDING AND SELF-LEVELING INSTALLATION OF CONCRETE MASONRY SYSTEMS”; U.S. Provisional Patent Application 61/258,352 filed on Nov. 5, 2009 entitled “SYSTEM AND METHOD FOR PRECISION GRINDING AND SELF-LEVELING INSTALLATION OF CONCRETE MASONRY SYSTEMS”; and U.S. Provisional Patent Application 61/319,999 filed on Apr. 1, 2010 entitled “SYSTEM AND METHOD FOR THE HIGH-SPEED APPLICATION OF GROUT TO PRECISION GROUND CONCRETE MASONRY AND SELF-LEVELING INSTALLATION OF CONCRETE MASONRY SYSTEMS”; all of which are incorporated fully herein by reference.
Number | Date | Country | |
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61230358 | Jul 2009 | US | |
61249619 | Oct 2009 | US | |
61258352 | Nov 2009 | US | |
61319999 | Apr 2010 | US |
Number | Date | Country | |
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Parent | 12466972 | May 2009 | US |
Child | 12848438 | US |