Patent Application
20150013255
The present invention relates generally to methods of manufacturing and construction, and specifically to commercial construction using cementitious materials. In this specific application precast/pre-stress concrete and autoclaved aerated concrete (AAC) to construct habitable multi-level buildings via the synergism of uniquely designed precast concrete support columns and beams, AAC beams, AAC floor panels and/or steel decking, sheer walls and exterior AAC panels with methodologies required to fasten the components.
One of the wisest people in history. King Solomon, is recorded in the Old Testament of the Bible as having constructed a temple for God by manufacturing individual dimensional material off site and then transporting members to the site where they were assembled. Despite this extensive history, the present invention overcomes the negatives and inadequacies of current methodologies inherent in precast systems that are disqualifying precast/pre-stressed concrete as the primary structural system in habitable multistory buildings. While precast is used for exterior facing, almost all habitable multi story buildings are currently being either constructed out of steel for speed or poured at site concrete for cost effectiveness. Precast on a whole is currently used more specifically for parking decks and highway bridges and the like.
The problems with current alternatives to precast are that steel is expensive and has a negative environmental impact in manufacturing and poured at site concrete is labor intensive and time consuming due to forms and shoring required.
Prior art for precast, such as Piggins U.S. Pat. No. 1,380,324, May, 1921 are elementary first attempts of precast units being transformed into monolithic structures by pouring finishing concrete which are not economically practical in application. There are some prior art composite steel and precast systems such as Fisher, et al. U.S. Pat. No. 5,704,181 Jan. 6, 1998, that shows steel columns and beams with precast floor panels, but it is basically a standard steel support system with heavy and difficult to manufacture and transport precast floors. Other systems such as Perrin U.S. Pat. No. 5,867,964, Feb. 9, 1999 rely on complicated and exacting fastening and interlocking mechanisms.
While the concept of reinforcing and joining precast pieces by employing steel bars that extend beyond one piece and are inserted into another is common practice in field and prior art as in Simanjuntak U.S. Pat. No. 5,809,712, Sep. 22, 1998. These systems require welding and/or cumbersome precast floor slabs. Wetton U.S. Pat. No. 5,161,340, Nov. 10, 1992 and Simenoff U.S. Pat. No. 5,123,220, Jun. 23, 1992 are typical examples of precast concrete structures that require many plates, fasteners, etc. and require exact placement in the field. Simpler methods of securing precast pieces together, like having rebar pass through corrugated sleeves arid then sleeves filled with grout to secure, have problems of: no guiding system to center the rebar in the sleeve so that the rebar will not rest directly against the wall of the sleeve that causes an inferior bond, time consuming requirement of pre-marking pieces so workers can know correct positioning that introduces element of human error, maintaining correct alignment and position without concern of subsequent movement, the fundamental problem of employing metal sleeve that is corrugated so that grout can bind rebar since concrete does not adhere to a smooth metal surface sleeve and all the construction problems of crane positioning and securing sleeves to form precast pieces, that crane and labor costs can exceed savings in a precast system. There are alternatives to corrugated sleeve systems, such as splice systems, but they tend to be expensive, do not align easily and still require excessive crane and labor time.
In constructing a multistory building, prior art typically places columns in a pattern at approximately 20′ by 35′ on center with the negative consequence of the more columns a building has the greater the material use and the less flexible the floor plan.
Prior art solid structural beams being placed on columns has problem in attempting to get as much concrete in as compact a space as possible; hence openings in beams are detrimental to structural strength. The prior art requires mechanical sprinkler systems and air ducts suspended below structural beams with the negative consequences of adding height and volume to each floor. This additional height necessitates additional structural components and exterior surface area, as well as interior air space that must be heated and cooled. All these factors not only add to construction costs, but also to operational costs for owners.
Prior art and current methodologies for poured in place system require extensive forming and support systems that must stay in place while concrete cures. These shoring systems are incredibly labor intensive and cause great delay by prohibiting all other trades from beginning work until they are removed. These shoring systems also have negative environmental impact due to large amount of lumber wasted and the requirement for steel.
Precast has negatives in manufacturing requiring forming multiple welding plates and then constructing at site that causes crane delays as pieces are positioned and then held in place by several workers while being welded. Precast pieces simply positioned in grouted precast seats lack ability to become a truly monolithic reinforced structure.
Current poured floor systems and prior art construct an approximate 10,000 square foot floor area per level in an industry accepted average construction rate of a seven-day cycle. This includes set up and pouring concrete floors, but does not include long term curing that requires the cost and labor of additional shoring, etc. Alternative decking floor systems never realized the reinforcing attribute of decking due to deficit of generous hole space left around weld bolts, etc., allowing movement in decking and so prevent decking from actualizing its potential to be a diaphragm without reinforcing concrete.
In regards to prior art flooring systems, an example is U.S. Pat. No. 5,507,124 Tadros, et al. Apr. 16, 1996 which shows a concrete framing system requiring bolts, reinforcing wires being placed and then poured concrete to secure, also columns pass through openings in beams and beams rest on fastening devices on columns. This and all other systems are environmentally unfriendly requiring a lot of lumber waste and cause a dangerous and dirty environment for workers and a liability for owners.
To overcome poured in place flooring, precast floor systems have been proposed but they have not proven practical due to manufacturing, transportation and installation difficulties associated with such heavy and bulky pieces of precast.
In regard to precast, and specifically prestressed, there is a great need in casting methodology for improvement in reusable parts and lessening time consuming and labor intensive set tip.
Smaller cementitious block buildings require bond/ring beams that are poured in place requiring labor and material costs. Until teachings of present invention there have been no alternatives to bond/ring beam.
Stairways are an instrumental part of commercial buildings and usually are steel framing welded together at site and then poured with concrete which require labor intensive, skilled workers.
When buildings are constructed higher than seven stories, they must add sheer walls, transforming building from a precast structure to a sheer wall structure. Sheer walls have many manufacturing and construction problems when precast systems are employed, similar in nature to problems of precast beams and columns, as well as downtime of the crane while waiting for shear walls to be welded in place. When sheer walls are formed and poured at site they require a large amount of labor and time.
Most commercial multi-story buildings of prior art also have problems with very low R-factor insulating exterior wall systems that are nothing more than architecturally finished concrete slabs. They are labor and time intensive due to requiring precast welding plates, additional insulation and interior wall build out and finish. Prior art AAC exterior wall panels required post autoclaving for architectural relief, work that is difficult on large pieces and causes unusable waste and required labor intensive and time consuming fastening systems.
Exterior panels of AAC currently also have architectural deficit in design having to either be coated with stucco or, to achieve a higher quality finish, have tiles of marble, granite, or the like fixed to surface. There was no architecturally aesthetic product that supplied the water proofing and vapor permeability AAC requires between either a plain common stucco or completely new solid surface material to architecturally finish the exterior AAC panels.
Prior art of manufacturing and installing the exterior AAC wall panels is to individually lay them on floor and position them inside structural columns with the result of difficulty of manufactured uniform exterior finish. To accomplish a uniform exterior finish by suspending exterior panels to the exterior race of a building frame requires complicated and time consuming methods of individually installing each panel that does not overcome difficulty of being drawn tight together.
Therefore, there is no prior art that feasibly employs the cost effectiveness and precision of precast concrete with advantages of strength and speed of steel systems, while simultaneously reducing building volume and that is simple and quickly constructed to make a monolithic structure.
Accordingly, several objects and advantages of the present invention are:
Further advantages include:
Other advantages are to provide a much cleaner, safer working environment for construction workers, to improve building quality while reducing labor costs, materials, and weight of structure, to provide savings in interest costs for construction loans and simultaneously a quicker realization of income from tenants by reducing construction time and costs, to reduce operational costs for owner by providing a substantial savings in utilities by increasing R-values of exterior walls and to provide a more environmentally friendly habitat.
This invention also helps the environment for it uses precast concrete and AAC so that no lumber is used and wasted for shoring, etc. AAC is known as an environmentally friendly material as some factories have been recognized as “Green Factories.” Given the current rising costs of utilities and concerns of global warming, these are considerable advantages that the present invention makes economically feasible.
The present invention includes methods of manufacturing and constructing a multi-story building comprising uniquely designed columns, beams, a flooring system, an exterior wall system, a stairway and means of securing the components.
On the first level, precast columns with the top surface having knobs with reinforcing rods protruding from their center are placed and secured to the foundation. Primary and secondary structural beams with funnel shaped sleeves on the underside ends corresponding to protruding reinforcing rods and knolls in the column are placed on columns with reinforcing rods passing through corresponding funnel shaped sleeves in the beams without the use of welding or mechanical fasteners.
The next level of columns have funnel shaped sleeves on the bottom corresponding to protruding rebar and knobs placed on top of the primary and secondary structural beams. Columns are then plumbed and the whole assembly is then grouted. This column and beam assembly is facilitated by knob-funnel design in precast pieces so that rebar is guided into the sleeves by funnel shaped sleeves in the beams and the beams are forced into proper position and aligned by knobs with the rebar centered in the sleeve for optimum grouting. The advantage is that the crane only has to lower and place the beams into the general area of the rebar protruding from the columns as the funnel design in sleeves will align beam and correct any bent rebar, etc., and the knobs correctly position, align and temporarily hold pieces together. Supporting columns are set and the rebar passes through beam's sleeves so there is no way beams are going to fall off the column and hurt anyone. It would take an earthquake just to move the beam off the column knob seat as the entire weight of the beam is pressing down on seat that has interlocking overlap that prevents movement. Optionally, a dab of grout can be placed on knob seat just before beam is lowered onto it for extra securing. After the first level of beams are set and the next level's columns are positioned and plumbed, it is only then that the system is grouted with the result being all pieces become monolithic without welding or the use of fasteners.
The primary, secondary, cross and AAC beams are then placed on columns or into precast seats or joist hanger that are secured in indentations so no measuring is required. Workers simply put it into position and then grout joints. The beams can be permanently attached to each other employing either of this present inventions two teaching: one a self-locking mechanism and the other a self-locking clip fastener.
Then the decking is attached to beams using a fastening system that employs actualized moment potential of decking, or instead, AAC panels are used employing system that provides moment via R-screws being used to secure AAC floor panels into composite pre-stressed/AAC beams. Both systems are installed in an area not directly under where the next row of beams and columns are being set. The previous floor's deck is poured after subsequent level floor's decking is installed so decking acts as a safety net and prevent injury if a precast piece were accidentally dropped. Mechanics can be working in areas with or without decking poured, but preferably after decking has been poured. In an AAC floor panel system, all sprinkler, electrical, etc., are placed before topcoat is poured.
The three levels of assembly are thereby coordinated so that it is now possible to continue construction for as many floors as are desired uninterrupted. It is also possible for precast system to be built several levels in advance of pouring decking. The present invention's system makes it possible to construct and pour 10,000 square feet of area in three days instead of standard seven days with much less labor and material.
The exterior perimeter columns can be either a composite of precast concrete with AAC inserts that are cast into the column or precast with receiving voids and steel created by a special mold. The AAC exterior panels are then aligned to precast column's AAC inserts and simply screwed onto columns employing an auger screw. AAC receptor inserts provide placement for workers, extra insulation to prohibit temperature transfer from fastening mechanism and facilitate installation in a much quicker manner than welding, and horizontal rebar placement using prior art is not possible. The panels can simply be hung onto columns and grouted. The column's shear strength is maintained as grouted AAC inserts or voids do not interfere with tension cables or reinforcing.
Both floor systems require a concrete finish pour, but unlike prior art, the present invention installs exterior panels before the floor is poured and the panels act as a form for final pour and can be integrated into floor thereby compounding the strength of the building.
The exterior panels are minimum R-30 as compared to minimal R-value for standard precast concrete. Exterior panels have architectural features uniquely manufactured into them at factory during cutting stage of production. AAC recycling planer/molder for adding architectural relief to exterior panels facilitates ecological recycling with advantages in time and labor savings as compared to procedures currently used on post autoclaved, cured AAC. Exterior panels employ a unique coating specialized for AAC that is water proof, vapor permeable and has aesthetic qualities far superior to simple stucco.
The stairway is basically precast and requires no welding to construct, only simple grouting and optional screwing to set.
When buildings go higher than seven stories, the structural requirements mandate sheet walls to be employed for additional reinforcing, and by employing the knob and tunnel sleeve system coordinated with clips and grout fasteners the corners and wall sections are joined quickly and permanently so that the crane has no down time holding pieces in place as required in prior art.
Several alternative fastening systems are presented for securing and/or attaching building components together that are quick and easy and yield the strength and advantages of welding but are simply grouted instead of the extra time, labor and cost welding requires.
Floor and roof joists/beams are secured to walls employing unique system that eliminates need for bond/ring beam by employing the diaphragm of floor or roof, thereby enabling a building to be constructed unimpeded.
The building is started with a foundation and first floor support columns being secured to/in the foundation or slab. Columns are set typically on 40′ centers and then plumbed and anchored.
Precast support columns 20 are approximately 20″×20″×9′-6″ high from base to top, except those columns supporting primary beams that are 24″×24″×9+″ high. This provides a 9′ high floor to finished acoustical ceiling and 6″ clearance for lights under all support beams, except for under primary beams that have clearance for ceiling and wiring but not lights.
Support columns have precast tunnel shaped sleeves 21 in the base for receiving corresponding reinforcing rods of rebar. Rebar is simply installed at site (
Column's top has knobs 22 corresponding to beam's base funnel sleeves 21 that receive rebar. The unique funnel shape of sleeves facilitates receiving the rebar by acting as a guide and additionally centers and positions piece being attached, whether beam or column, and then locking the piece onto knob to prevent movement from the correct position. The columns are anchored by simply filling precast area of voids 12 that are larger than rebar with epoxy grout. Columns have cast within them a receptor for rebar 11 that has pipe threading manufactured on it matching threads in receptor 23 so that reinforcing can be installed at site. By employing this receptor, columns do not have to have a rebar protruding from top of the precast forms or in transit.
Columns have cast into them AAC inserts 24 for receiving fasteners of exterior panels of AAC or alternatively interlocking fasteners shown in
After correct placement, plumbing and grouting of the columns on the first level, beams are installed. Beams, identified as primary 30, secondary 31 and cross 32 are similar in design except for size and precast features. Primary beams 30 being approximately 42″ wide×24″ deep×40′ long, secondary beams 31 being approximately 36″×18″×20′ long, cross beams 32 being approximately 24″×18″×20′ long, and AAC beams 33 approximately 8″×18″×20′ long. Perimeter beams 34 being approximately 24″×24−×20′.
One of the invention's teachings is a concrete structural beam with perpendicular utility voids 39 for allowing mechanical duct, sprinkler systems, etc., to pass through them. Utility voids 39 are unique in being strategically located for both structural purposes as well as functional requirements of mechanical system so that a grid system results for ease of design and a reduction of as much as 33% of prior art's vertical height dead space is removed from the building.
The structural beam system represented in
The perimeter beams 34 have unique end design 36 to finish corners flush with rebar 11, knob 22 and funnel system 21 locking corners in place. Perimeter beams 34 have precast seats on only the interior side and no utility voids. Perimeter beams can also have AAC inserts 24 to attach AAC exterior panels.
Beams do not require a curing time as they are secured by sleeve 21 and knob 22 system and pouring an epoxy mortar permanently sets beams. This adequately secures the structural system so than an entire floor level can be constructed and secured without any welding, mechanical fastening or further bracing other than temporary X bracing so that construction can continue unimpeded by prior art's welding and/or shoring.
This entire interlocking beam/joist floor support system can have one or more 40′×40′ quadrants, or even one or more smaller AAC 20′×20′ quadrants, rotated 90 degrees if required for mechanical duct work, sprinkler system, etc., by simple design of interchangeable block outs 32A and 35A and joist notches 62 in primary and secondary beams.
A top view of partial floor plan engineered for structural beam system is shown by
The flooring system
The flooring system employing AAC panels sprinkler system's CPVC pipe branches 51 embedded into the AAC panel's enlarged key joint at 6′ centers, 3 panels from the beam. The precast beams have a void for accepting sprinkler pipe formed 64 across the top.
The sprinkler system's main pipe 51A runs in the gap between the panels and beam. Sprinkler heads 54 protrude through the ceiling, that is the bottom face of the AAC panel, as code requires. Additional heads can be placed at minimal cost so that future remodeling of pace presents no problems, as even acoustical ceiling can be installed in rare instances to hide additional runs if required.
After testing for pressure and drainage, the sprinkler pipes are covered in floor's cement topcoat that can be colored or stained and become a finished floor without the health hazards of carpet that contribute to “sick building” syndrome.
The AAC floor panel system has on the beams a marking system 57b so workers can easily locate the correct placement for fasteners 130 employing drill guide 57a. The triangulated point fits into beams triangulated void 57b and straight front plate aligns square. The worker simply eyes the alignment plates in imaginary crosshairs 57c to drill fastener directly into AAC insert 24. The AAC insert is held into precast mold by guide 24a. Alternatively to AAC insert is a beam void 55 that is precast using a large plastic screw 56 that when removed from mold it leaves a void cavity in the beam into that fastener point sits after being drilled through AAC floor panel and when epoxy is poured info the fastener and flows out of fastener the void is filled and thereby locks the panel into place.
The precast utility voids 39 in the beams are formed circular 39 or to accommodate required duct volume while retaining beam strength formed oval 39A.
A top view of partial floor plan for an alternative AAC floor panel system
The exterior AAC panel system in
The beam precast form system is represented in
The column precast form system is represented in
The process of disassembling the form assembly is to remove nuts from ends of void form extensions 92, 94, then remove top plate 91 off column form 90, sliding it over extensions and then with wrench type device applied at end of extension 98 to remove the entire rebar void form 93 leaving the rebar anchor 97 embedded in concrete column. At site reinforcing rebar 11 will be installed as
The form for base of column is assembled and disassembled similarly to the top as detailed. The distinction is in the ends of rebar voids 93 in bottom have female threaded receptors 190 cut at angle so that the grout sleeve form 192 that has a male threaded bolt type end 194 can be screwed into base rebar void form 93 and thereby form a continuous void starting on exterior face of column channel with grout sleeve 191 and continuing to the rebar void form 93 and then to base 91A. At the site this will allow grout to flow all the way through the voids in knob and through support beam to lower level's column top, thereby making one monolithic piece of all precast pieces, with no welding nor mechanical fasteners.
The precast sheer wall 100 incorporates this invention's knob and sleeve system so that an entire wall sections for each floor can be precast and then assembled at site in order represented numerically in
To produce exterior panels with custom face relief a teaching is the AAC recycling planer molder 110 that has a cylinder shape with hollow core 112 and planer molder blade 111 that is attached from the backside so nothing impedes ground AAC. The AAC recycling planer molder can have water added to top 120 to facilitate expulsion of the ground “green uncured,” recyclable AAC waste 70B that exits from the base. The interior wall of shaft 112 has downward spiraling grooves 113 and hollow core is slightly wider at base than at top that employs centrifugal force to force AAC waste down as planer spins. The AAC recycling planer blade 111 is angled as shown to force ground AAC waste 70A into hollow shaft 112 and the centrifugal force of spinning action forces AAC waste against grooved shaft wall and down. When AAC reaches the overlap area 115B the AAC is forced to leap over intake slot and go against outer wall to repeat cycle until expelled out base. When AAC is cut, usually wire 116 is used when AAC is still green before if has hardened and been autoclaved. While in this stage the AAC can be recycled and reused unlike after it has hardened and/or been autoclaved. The left side of
By employing interlocking clip system 120 and 121 precast pieces can be locked into position and together without requiring crane to hold pieces while being welded. FIG 12A shows how clip 121 locks onto reinforcing bracket 120 and by simple grouting 182 is permanently fastened without welding.
When attaching AAC pieces such as a panel 70 to structure such as column 20 via AAC insert 24, fastening screw 130 is employed. The fastening screw has special threads 136 on only front half of a hollow shall 135A. The hollow shaft 135A has reverse rifling 131 to receive AAC dust that is ground up by screw special tip 135 that relieves pressure and facilitates screws ability to go through 12″ of AAC. The rear half of fastening screw's shall is smooth without threads so that there is still a bearing capacity of screw by the shaft fitting smoothly against walls of AAC, but by special threads 136 pulling screw into AAC and head 138 of screw pulling AAC panel tight against the grouted surface of the piece to that it is being secured. The head of the screw has two slots 134 that facilitate countersinking the screw and when the surface is finished the screw head is grouted that prevents screw from backing out, and in severe applications a securing pin 132 is driven that prevents screw from backing out. Once AAC pieces are fastened and pin set, then counter sunk screw's head can be covered by decorative architectural covers 139A and 139B that are attached by grout.
A fastening system that is an alternative to screws for exterior AAC panels 70 is the hanging clips 145 and 145B system. Prior art
This invention's teaching in
The balloon coupling sleeve
An alternative to the balloon coupling sleeve is the threaded coupling sleeve 180. First step is to slide special circular reinforcing rebar 172A onto precast's rebar 11. Then screw threaded coupling sleeve 180 onto rebar 11 and slide circular rebar 172A over threaded coupling and screw it onto threads 186 on coupling sleeve. After member has cured, simply remove coupling sleeve by unscrewing. At site this invention's hour glass threads 183 is screwed into the void's threads and the rebar inserted into coupling sleeve passes through hour glass threads 183 that has holes with reducing diameter, as diagram 185 shows, at end towards knob seat 22A. The hourglass thread 183 also has notches 184 so when high strength grout is installed it locks whole system into place. A funnel shaped receiver 187 can assist rebar fitting into hourglass thread 183.
A unique and interlocking rebar pattern 188 that acts like a paper clip is fitted over a group of coupling sleeves and then poured to become a monolithic precast system requiring no ties, etc., to secure. As shown in
This application claims the benefit under 35 U.S.C. 119 of provisional patent application 61/785,140 filed Mar. 14, 2013.
| Number | Date | Country | |
|---|---|---|---|
| 61785140 | Mar 2013 | US |
