Abstract:
A modular structure foundation system that requires no heavy equipment, minimal site preparation, bag concrete and crushed rock, and can be easily assembled by a small crew. The foundation consists of a number of box bar joists that are square units which are assembled based on a grid layout. The box bar joists are supported by foundation steel columns that are embedded into the ground. No forms or other complex structures are needed for the installation. Once the columns are installed, the box bar joists are installed using a unique leveling system. Once the box bar joists are level and secured to the columns, the foundation is complete. The use of the box bar joists also allows for expansion or contraction as additional box bar joists can easily be added or removed from the foundation. Once the box bar joists are in place, the foundation is ready for building.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to foundation systems and particularly to foundation systems for modular type construction. 
     2. Description of the Prior Art 
     Constructing shelters has been an essential part of human development since the beginning of civilization. In the last century, buildings have been developed beyond the ordinary “stick-frame” construction into new modular designs. Both types of construction, however, use the same types of foundation, which consists of a concrete footing and some type of concrete or block walls. The building is built upon these walls typically by bolting a bottom sill plate to the top of the foundation wall using “J” bolts that have been embedded in the concrete. 
     Although these walls have been proven to be strong and reliable, they require quite a lot of site preparation, including surveying, grading, excavating, rebar install, setting concrete forms, pouring concrete (or building wall of block), and then back filling around the foundation. Additionally, in many areas, the foundation wall is waterproofed, which adds additional costs and time. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The instant invention eliminates all of the problems associated with conventional concrete type foundations. It consists of a modular structure that requires no heavy equipment, a fraction of construction time, minimal site preparation, bagged concrete, and can be easily assembled by a small crew. The foundation system is hurricane proof and tornado proof. It can be assembled and dismantled, for either emergency housing or permanent construction. It allows additions to be added at any time, simply and easily. Moreover, it allows parts of the building to be removed if desired. The foundation system allows an owner or contractor to build it quickly and easily. 
     The foundation consists of a number of box bar joists that are square units that are assembled based on a grid layout. The box bar joists are supported by foundation steel tube columns that are embedded into the ground. While installing the foundation columns does require bag concrete and crushed rock, no forms or other complex structures are needed for the installation. Once the columns are installed, the box bar joists are installed using a unique leveling system. Once the box bar joists are level and secured to the columns, the foundation is complete. The use of the box bar joists also allows for expansion or contraction as additional box bar joists can easily be added or removed from the foundation. Once the box bar joists are in place, the foundation is ready for building. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a layout grid (LG) used in installing the foundation system. 
         FIG. 2  is a detail view of a connection node bolt (CNB) in the layout grid (LG) of the foundation system. 
         FIG. 3  is a detail view of an auger end post and turnbuckle used in the layout grid (LG) of the foundation system. 
         FIG. 4  is an exploded view of the connection node bolt (CNB) used in the layout grid (LG) of the foundation system. 
         FIG. 5  is an expanded detail view of the major components used in the foundation system. 
         FIG. 6  is a top plan view of a portion of the foundation system. 
         FIG. 7  is a top perspective view of one of the box bar joists (BBJ) used in the foundation system. 
         FIG. 8  is a front elevation view of one of the box bar joists (BBJ) used in the foundation system. 
         FIG. 9  is a side elevation view of one of the box bar joists (BBJ) used in the foundation system. 
         FIG. 10  is a top plan view of one of the box bar joists (BBJ) used in the foundation system. 
         FIG. 11  is a front elevation view of two box bar joists (BBJ) used in the foundation system. 
         FIG. 12  is a perspective detail section view of an alignment of 4 box bar joists (BBJ) used in the foundation system. 
         FIG. 13  is a top perspective view of one of the foundation crawlspace leveling lifts (CLL) used in installing the foundation system. 
         FIG. 14  is a bottom perspective view of one of the foundation crawlspace leveling lifts (CLL) used in installing the foundation system. 
         FIG. 15  is an enlarged detail view of the leveling toggle bolts (LTB) on one of the foundation crawlspace leveling lifts (CLL) used in installing the foundation system. 
         FIG. 16  is an enlarged side view of one of the leveling toggle bolts (LTB) on one of the foundation crawlspace leveling lifts (CLL) used in installing the foundation system. 
         FIG. 17  is a perspective view of one of the steel tube columns (STC) used in the foundation system. 
         FIG. 18  is a side elevation view of one of the steel tube columns (STC) used in the foundation system. 
         FIG. 19  is a top detail view of one of the steel tube columns (STC) used in the foundation system. 
         FIG. 20  is a perspective view of the components used as part of the aligning bar connector (ABC) system. 
         FIG. 21  is a detail perspective view of the various aligning bar connector (ABC) systems. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The first step in the construction of the foundation is to prepare the site and lay out the grid. Referring now to  FIGS. 1-4 , the grid system  100  is shown. Prior to erecting the grid, it is good practice to ensure the site is surveyed by a licensed surveyor to confirm the location of all property lines. In the preferred embodiment, the best site is one that is nearly flat with no more than a six (6) inch rise (slope) from one side of the building exterior to the other in both directions, ensuring all the foundation poles are the same length; slopes greater than six inches will require longer foundation poles. As an alternative, the site can be graded prior to construction. In the next step, level any grade high points greater than six inches or fill areas lower than six inches with crushed rock or fill material and compact so that the area is reasonably smooth and free from irregular surface changes. Next, install wood stakes at the corners of the exterior walls, tie string between the wood stakes six inches above the construction site high point and ensure it is horizontal with a line level. The string may also be run diagonally to each stake to better view the highpoints of the site and make leveling adjustments accordingly. 
     Once the site is prepared, the next step is to unroll the site layout grid (LG) in the location where the foundation is to be assembled. The assembled grid is shown in  FIG. 1 . The grid is made up of lengths of coated wire rope. In the preferred embodiment, this is stainless steel vinyl coated wire rope, ⅛″ Bare OD, 7/32″ Coated OD. The wire rope is cut into sections and secured to end posts. 
     The grid may be assembled prior to deployment in the field. Note that for the system, the grid  100  has rows  101  and columns  102  of wire rope to make up the grid. The intersections  103  are fitted with special bolts and other hardware called connection nodes, which ensure that the intersections are properly spaced. The foundation poles are placed at these intersections so it is important to make sure they are properly positioned. Once the site is ready the grid is prepared; stretch the grid so that it is flat on the ground. The grid is anchored at the corners with two augers  104  at each of the corners. The augers are installed twelve (12) inches below grade to ensure the wire is taught, and laid directly on grade. 
       FIG. 2  shows details of the grid  100  showing one of intersections  103  and the hardware for making up the corners of the rope grid  100 . Note that the ends of the rope are folded over to make thimbles  105  using clips  106  in the ordinary manner. The thimbles are placed on all lines leading to each auger. At each of the intersections  103  formed by the rows and columns are bolt assemblies  110  that hold the grid together. 
       FIG. 3  is a detail view of an auger and turnbuckle used in the layout grid (LG) of the foundation system. In this view, the actual attachments are shown. As shown, an auger  104  is shown with a thimble  105  on it. A length of wire rope is run out to a turnbuckle  108 . At the other end of the turnbuckle, the main row of the wire rope is attached. This rope runs the width of the foundation area, where it meets another turnbuckle assembly and another auger. The thimbles  105 , clips  106  and turnbuckles  108 , as a group, can be considered as a means for securing the rows and columns to the plurality of auger posts. Note the bolt assembly  110  at the intersection. 
       FIG. 4  is an exploded view of the connection node bolt (CNB) assembly  110 . At the bottom of the assembly is a ¾″-10 hex bolt  111 . This bolt is an ASTM A307 grade A bolts that is zinc plated. Note that it also had two grooves  112  formed in it as shown. These grooves  112  are used to hold the wire ropes that form the grid. The grooves allow the wire ropes  102  and  103  to fit within the bolt to produce a compact assembly. The wire ropes  101  and  102 , with the intersection  103 , are positioned between two flat washers  113 . Above the top washer  113  is a lock washer  114  and hex nut  115  as shown (or hex nylon lock nut replacing lock washer and nut). Note that the bolt and nut assembly described above can be considered as a means for fixing the intersection points. Note also that all of the components discussed above and shown in  FIGS. 1-4  can be considered as a “means of forming a grid”. 
     As noted, the grid can be assembled prior to field layout. Once the augers are set and the grid stretched on them and properly tightened, the outline of the wire four-foot grid pattern is transferred using white pavement marking paint (or its equivalent) sprayed onto the surface of the ground. Next, orange color marking flags are installed at all connector node bolt (CNB) locations; i.e., at all four-foot wire spacing&#39;s. These flags are pushed deep into the soil so each flag is just visible to avoid pulling out the flag during construction. Once the flags are set, the layout grid (LG) can be rolled up and removed as the site is now prepared for the foundation installation. 
     This system uses rigid box bar joists (BBJ) set on plies. Unlike conventional pile foundations, however, the piles (called steel tube columns (STC) here) are attached to a leveled set of box bar joists (BBJ) before they are cemented into place. To do this, the following components are used, as shown in the following figures. 
       FIG. 5  is an expanded view of the major components used in the foundation system.  FIG. 6  is a top plan view of a portion of the foundation system. At the top of the figure are four box bar joists (BBJ)  10 . Below them are four crawlspace leveling lifts (CLL)  20 . Below them are four columnar supports called steel tube columns (STC)  30  that are shown embedded in the ground  1000 . Note that the steel tube columns (STC)  30 , crawlspace leveling lifts (CLL)  20  and box bar joists (BBJ)  10  are the same for a flat site. The installations directions listed below are for a flat site setup. A sloped site setup is the same except that the steel tube columns (STC) are different lengths to accommodate the uneven ground. 
     Each of the components is discussed in detail below, along with complete installation details. 
       FIG. 7  is a top perspective view of one of the box bar joists (BBJ)  10  used in the foundation system. Each BBJ  10  has a top chord  11  that is made up of four pieces of angle iron that are welded together as shown. In the preferred embodiment, each of the top angle iron pieces is a 4″ by 4′ by 0.25″ with two 48″ long and two 40″ long pieces of angle iron. Four ⅞″ inch holes  12  are drilled to receive four ½″-13 bolts  1 ″ long  12   a , bolt head height is ¼″. The bottom chord  13  of the BBJ  10  is made up of smaller angle iron. In the preferred embodiment, the longer frame is made up of four pieces of 2″ by 2″ by 0.25″ by 40½″ long angle. Additionally, in the preferred embodiment, four ½″-13 studs  14 ,  1 -inch long are attached as shown to each corner with ¼″ steel plate tabs  14   a . Between the top and bottom chords is a web  15  of #3 rebar, or equivalent, this is welded to the top and bottom chords. Note that the overall height h (see  FIGS. 8 and 9 ) of the BBJ  10  can range from 12 to 30 inches. In the example shown the height h is 18 inches. 
       FIG. 8  is a front elevation view of one of the box bar joists (BBJ)  10  used in the foundation system.  FIG. 9  is a side elevation view of one of the box bar joists (BBJ) used in the foundation system. In these views, the top chord  11 , the bottom chord  13  and the web  15  are shown along with the tabs  14   a , studs  14 ,  7 / 8 ″ hole  12 , and ½″ hex head bolt  12   a . Note here, the height h is also 18″ and overall length of the top chord is 4′ and overall length of the bottom cord is 40½″ (dimensions may vary per structural calculations). 
       FIG. 10  is a top plan view of one of the box bar joists (BBJ) used in the foundation system. Here, the top chord  11  is shown. Note that the corners  11   a  are notched. This is to facilitate the assembly, as discussed below. Note here, that the holes  12  and bolts  12   a  are also shown adjacent to the studs  14  and tabs  14   a.    
       FIG. 11  is a front elevation view of two box bar joists (BBJ) used in the foundation system. Here, two sections of BBJ  10  are shown placed adjacent. This is how the BBJs are aligned during the construction.  FIG. 12  is a perspective detail section view of an alignment of four BBJs used in the foundation system. In this view, note how the holes  12  and the studs  14  are aligned. Note too, that the notched corners  11   a  come together to form a hole in the center of the assembled BBJs, as shown. This hole is used to secure the aligning bar connectors (ABC), as described below. All BBJs are galvanized and are coated with a bitumen coating. 
     As discussed above, the BBJs  10  must be arranged and leveled prior to attaching the steel tube columns (STC). To do this, a number of crawlspace leveling lifts (CLLs)  20  are used to support and level the BBJs. These CLLs can be considered as a means for temporarily supporting the box bar joints. Referring now to  FIGS. 13-16 , details of the crawlspace leveling lifts (CLLs)  20  are shown.  FIG. 13  is a top perspective view of one of the foundation crawlspace leveling lifts (CLL)  20  used in installing the foundation system.  FIG. 14  is a bottom perspective view of one of the foundation crawlspace leveling lifts (CLL) used in installing the foundation system. Each of the CLLs  20  consists of a base plate  21  that has four spikes  22  attach that extend downwardly from the base plate  21  as shown. Four angle braces  23  extend upward from the base plate (one is placed at each corner of the base plate). The braces  23  are attached to a top plate  24  as shown. Two leveling toggle bolts (LTB)  25  assemblies, which can be considered as a means for leveling the box bar joints, are attached to the top plate as shown. 
       FIG. 15  is an enlarged detail view of the leveling toggle bolt assemblies  25  on one of the foundation crawlspace leveling lifts.  FIG. 16  is an enlarged side view of one of the leveling toggle bolt assemblies. These assemblies are temporarily installed, as described below, and are used to level the BBJs and to support the BBJs and the STCs while the concrete for the STCs is curing. Each leveling toggle bolt assembly  25  has a long bolt  25   a  that is threaded through two nuts  25   b  that are welded to the top plate  24  as shown. A leveling nut  25   c  welded and fixed to the bolt is provided as a measuring device to move bolt  25   a  to the desired height, as discussed below. At the top of each of the toggle bolts  25   a  is a “C” holder and toggle clamp  25   d  that is riveted (and free turning) to the top of the bolt  25   a . In use, the bottom frame angle of a BBJ is placed in the “C” holder of the toggle bolt and clamped into place. Then, the toggle bolt height can be adjusted as needed, as described in the installation section below. Referring now to  FIGS. 17-19 , details of the steel tube columns (STC)  30  are disclosed.  FIG. 17  is a top perspective view of one of the steel tube columns (STC) used in the foundation system.  FIG. 18  is a side elevation view of one of the steel tube columns (STC) used in the foundation system. Each STC  30  consists of a top cap  31  and a lower column  32 . The top cap gas a 7″ square×¼″ thick flange  33  that is secured to a 6″ long, 2½ inch OD round bar  34 . In the preferred embodiment, the cap is galvanized; the top cap secures the BBJs top chord hex bolt  12   a . Below the cap is a lower column  32 . This column is a 3″ diameter steel tube  35 ,  3 / 16 ″ thick and is between 6 and 8 feet long. In the preferred embodiment it is galvanized and covered with a bitumen covering. The column has four ¼″×2″×2′ hurricane fins  36  attached as shown. Below the fins, four 2″ shear studs  37  are attached. Two steel angles  38 , 3″×3″0.25″, 4″ long are attached on opposite sides of the column. These angles have 9/16″ diameter holes  39  drilled in them (see also  FIG. 19 ). The angles secure the BBJs stud  14 , tighten with a ½″ hex net and washer. 
       FIG. 19  is a top detail view of one of the steel tube columns (STC) used in the foundation system. Here, the top cap  31  is shown. Note that the top cap has four 9/16″ perimeter holes  33   a  formed in it as shown, and a center hole  33   b  that is tapped at 1″-12 NC threads, 2″ deep. The cap  31  is placed into the lower column  32  and is welded to the lower column assembly. 
     Finally, another temporary component is shown on  FIGS. 20 and 21 .  FIG. 20  is a perspective view of the components used as part of the aligning bar connector (ABC) system. The aligning bar connectors (ABCs)  40  are made up of ⅛″ steel plates  41  that from a square perimeter and are reinforced by plates  42  that cross in the center as shown. At the four corners are steel tubes  42 , 1½ inch (nominal) milled ID, as shown. Four 1½ inch shoulder bolts  43  are placed in the tubes  42 . In addition, a number of spacers  44 , made from 2″ round stock and having 1½ inch (nominal) milled holes are used to support the ABCs when installed to the steel tube columns (STC) aligning them to the modular grid system. 
       FIG. 21  is a detail perspective view of various aligning bar connectors (ABC) to be used to align the steel tube columns (STCs). In this view, a single ABC is overlaid with 2 ABCs, followed by three, and so on. The ABCs  40  provide a locking overlay to secure all of the foundation components from above as part of the curing process, as discussed below. In practice, referring to  FIG. 6 , the first ABC is placed atop the first BBJ. The four shoulder bolts are then secured to the center holes  33   b  on the top caps. Once this is done, the second ABC is secured to the adjacent BBJ. Note that this ABC overlaps the first at one edge. Thus, two of the bolts used in the first installation are removed and then fed through the steel tubes  42  on both of the ABCs. Obviously, spacers  43  are used to support the other end of the second ABC. In a similar manner additional ABCs are installed overlapping them as needed until the entire foundation is covered. 
     To install the foundation, the following steps are used: 
     First, set up a laser level at a far corner of the grid that has been laid out as described above. Ensure the laser level is placed in an unobstructed sight line of all marking flags. This corner is opposite of where the first BBJ  10  is to be placed. The start location may be at any corner. In the preferred embodiment, the laser level height is 27″ above grade. 
     Next, the grid area is inspected to remove debris, vegetation, large rocks and tripping hazards. All paint markings and marking flags are verified as being visible. Note that as described above, the marking flags and paint stripes are on a four (4) foot grid. 
     Beginning with the first grid square, (opposite diagonal end from laser) auger two rows of STC holes (Depth varies per location). These holes should start at the short length of the building and next row over. 
     Next, tamp down and compact the exposed earth at the bottom of each hole. Then pour 1 cubic foot of crushed rock into the hole and tamp and compact the rock. 
     Once the rock has been compacted, place a paver (stone or plastic) cover over each hole. In this example, these holes are called row one (1) and two (2). 
     Next, place four CLLs  20  in the starting corner of the grid (herein called square #1). As shown in  FIG. 6 , place each of the CLLs centered between the holes drilled for the STCs around the perimeter of the first starting corner square #1. 
     Place the perimeter CLLs  20  with the screw hold up toggle lock bracket on the inside of the square (one toggle lock will be unused at the perimeter, as shown in  FIG. 6 ). 
     Note, the bottom plate stakes are not pushed into soil more than an inch at this time. Place a BBJ  10  on the first square CLLs  20  into the channel next to the toggle bolt clamps again as shown in  FIG. 6 . Ensure that the CLLs are in a near vertical position. Then, the bottom plate stakes are hammered into the ground. 
     Next, the leveling/toggle bolts are adjusted (up or down) until the welded leveling nut is centered in the laser level beam. (Note: in the preferred embodiment, the leveling nut is welded to the leveling/toggle bolt. 
     These steps are repeated for each CCL. When first CCL is level (i.e., when all leveling nuts at the same height), this is the height of all the BBJs  10  used in the system. 
     Next, after ensuring that the laser level is perfectly level at all times, begin working in the second grid square. As before, the next three CLLs are placed in the adjacent grid square. Similarly, the next BBJ is placed atop the three new CLLs, next to the installed BBJ. 
     Next, an STC  30  is placed in each of the four holes at square #1. (Note: STC may need to be placed earlier, depending on depth of hole from structural analysis). Each STC is raised up and the column cap is bolted to the BBJ hand tight. See  FIG. 6  for the position of these components. Next four STC are installed in the grid square #2, as before. 
     Next, an aligning bar connector (ABC) is bolted into the center of each column cap  33   a . See  FIG. 6 . Next, the bolts on the column cap are wrench tightened on each BBJ. Then concrete is poured into each STC hole. 
     The remaining grid squares for the foundation assembly are completed using the same process as in grid squares #1 and #2. 
     After seven (7) days from the last concrete pour, the CLLs are removed, and earth is pushed back into the holes in eight-inch lifts. Leach lift is compacted. Compact a small amount of earth two inches high around the top of each STC hole. 
     At this point, the foundation system is complete and ready for building upon. 
     Note that the ABCs are not removed at this time. They are removed only when floor joists assemblies (FJA not part of this system) are installed. Note: an alternate method of construction uses floor joists assemblies (FJA) in place of the ABCs. 
     Finally, a crawlspace vapor barrier may be installed later in the construction process, for example, after installation of roofing. 
     The present disclosure should not be construed in any limited sense other than that limited by the scope of the claims having regard to the teachings herein and the prior art being apparent with the preferred form of the invention disclosed herein and which reveals details of structure of a preferred form necessary for a better understanding of the invention and may be subject to change by skilled persons within the scope of the invention without departing from the concept thereof.