Abstract:
Connection devices to improve utilization of synthetic deformed bars to transfer tensile loads. Attachment devices for connection of thin wall face panels to mechanically stablized earth walls with minimal tensile loads. Horizontally disposed synthetically deformed bars or other tensionable members utilized to combine precast retaining wall elements.

Description:
[0001]    This application is a continuation in part of U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002 which is a continuation in part of PCT Application # PCT/US01/05733 filed Feb. 22, 2001, which claims the benefit of the U.S. Provisional Patent Application No. 60/184,049 filed on Feb. 2, 2000. These applications are incorporated by reference herein. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    Various methods have been used to construct precast walls for retaining earth, soil, sand or other fill (generally referred to as soil). A typical precast wall system is disclosed in U.S. Pat. No. 4,914,876, assigned to the Keystone Retaining Wall System, Inc. by Paul J. Forsberg. The Keystone Patent illustrates a typical modular block wall system wherein the wall face is comprised of concrete masonry units connected to geosynthetic wall reinforcement layers. The geosynthetic tensile inclusion members for this type of retaining wall structure are typically referred to as “geogrids.” 
           [0003]    A disadvantage of such a system is that a considerable amount of hand labor is required to install the numerous small block facing units of the block wall system. This requirement limits the amount of wall structure that can be completed in any work shift. In addition, if the wall is placed on weak foundation soils, a manifestation of wall settlement is cracking or more significant crushing or crumbling of the facing units. If wall settlement is excessive, the geogrid material can be sheared where it connects to the concrete masonry unit horizontal joints, which can result in wall failure.  
           [0004]    Numerous other types of concrete block mechanically stabilized earth wall systems are available. These systems, like the Keystone System previously described, mandate precise grading and compacting of the wall backfill to correspond to increments of the vertical height of the block facing units so that the tensile inclusion materials used to mechanically reinforce the retained wall backfill material can be placed at the horizontal joint elevations of the concrete masonry units. Although the material costs for these types of wall systems are low, the high labor costs for the various stages of wall construction can result in installed price of walls that are substantially higher than the material costs.  
           [0005]    Other mechanically stabilized earth walls include walls that use precast concrete panels for the wall facing elements, such as walls disclosed in U.S. Pat. No. 4,961,673, issued to Pagano et al., and U.S. Pat. Nos. 3,421,326; 3,686,873; and 4,116,010 to Vidal. Such wall systems require the use of metal reinforcing strips or steel grids as soil inclusion members in the wall backfill. Those members are connected to the precast wall panels to hold the panels in place and to provide stability for the wall backfill.  
           [0006]    A disadvantage of walls that use non-corrosion resistant metal soil reinforcement is that the metal soil tensile inclusion members are subject to corrosion, because the metal is in direct contact with the wall backfill. Numerous catastrophic failures have resulted from the effects of unchecked corrosion on the metal tensile inclusion members for these wall systems. Although soil inclusion members (e.g., metal strips or steel grids) can be galvanized to resist the corrosive effects of the oxidation process, this technique is not effective for all soil types due to the diverse mineral content present in some soils. Other methods, such as epoxy coating of the metal soil inclusion members, have been used to further resist the deleterious effects of potential chemical reactions of the soil minerals with the soil inclusion members. A disadvantage of the epoxy coating, however, is that the coating is easily scratched during the construction, which results in the exposure of the metal soil reinforcement to the corrosive effects of minerals present in the backfill. Also, epoxy coatings increase the costs of these systems.  
           [0007]    Another factor that increases the likelihood of premature failure of MSE walls that use steel soil reinforcement is the reduced sliding friction of the soil reinforcing material at the onset of the effects of corrosion. Because corrosion commences from the outside surface of the reinforcing material, the corrosive residue becomes the material that is in contact with the soil following the commencement of corrosion. The interface of the corrosion layer with the steel soil tensile reinforcement member is therefore the weak link. The remaining competent steel material may move with respect to the corrosion layer. Movement between the soil fill and the soil reinforcement may also occur. The ultimate result of this relative movement could be premature wall failure.  
           [0008]    Typical wall facing units for existing MSE systems in current use may range in size from 8″×16″ for block systems to 25 to 50 sq. ft. for precast panel wall systems. The concrete masonry block systems, due to the high unit weight and relatively small size of each block, do not require bracing or interlocking to hold the face units in a vertical position as the wall backfill is placed. Since the blocks are heavy (exceeding 100 pounds for some applications), the placement of the blocks is physically demanding, which adds to the placement cost of the facing units. MSE wall systems that use panels for wall facing are large in size compared to the block facing units, and the panels (typically between 25 to 80 sq. ft. in area) are held in place during backfilling operations by interlocking with previously placed or adjacent panels. For some systems, the facing units are “wedged” or leaned by other methods so that the effect of the interaction of the backfill pressure and the metal soil reinforcement will, in theory, force the panels into a plumb or vertical position. Panel placement for these systems requires experienced workers to erect the units so that the resultant structure will be vertical and not leaning either in or out of a vertical plane.  
           [0009]    Another broad range of MSE wall types that have been used extensively for permanent and temporary retaining wall applications are wrapped face, or confined fill layers, that form a geotextile MSE wall. These walls are comprised of an assembly of vertically stacked layers of wall backfill confined by closed face sheets of geotextile that are typically placed in horizontal planes within the wall backfill as the backfill is placed and compacted. For temporary walls, the face of these walls is the exposed geotextile material. The geotextile material that retains the fill at the face of each layer is wrapped back into the fill behind the face of the wall. The wrapped back geotextile is imbedded into the backfill material behind the face of the wall for each compaction lift of fill that is placed. One of the difficulties associated with the construction of these types of earth retention structures is that the wrapped back face portion of each backfill layer requires that an external forming system be installed in front of the face of the wall to hold the geotextile face at the proper alignment until the wrap back portion of the geotextile layer is sufficiently imbedded in the backfill adjacent to the wall face. The associated fill pressure prevents the wrap back geotextile from being displaced horizontally. The cost of labor associated with the placement and operation of the external forming system adds to the cost of these types of walls.  
           [0010]    Whether the geotextile wall is a temporary or permanent structure, a face forming grid is required during wall construction so that the resultant overall wall face will conform to the wall alignment limits. For permanent geotextile walls, it is necessary to cover the exposed wall face so that the geotextile will be protected from the deleterious effects of prolonged exposure to ultraviolet radiation. Although the geotextile material is corrosion-resistant with respect to the soils and minerals that the material may come into contact with due to the embedment in the wall backfill, the long-term effects of exposure to the sun can result in the ultimate deterioration of the wall face. There are various facing materials that have been used to cover the face of geotextile walls. The facing materials include, for example, sprayed concrete faces, precast or cast-in-place concrete panels. The use of a sprayed concrete faces requires that attachment fasteners, such as lengths of wire or pieces of rebar, be installed in the wall and protrude from the face of the wall to form a connection between the sprayed on concrete and the exposed geotextile surface. The disadvantage of walls with this type of face is that the wall surface is typically not uniform and not aesthetically pleasing. Additionally, if the walls experience any significant long-term settlement, cracking and spalling of the sprayed concrete face can occur.  
           [0011]    Precast facing elements have also been attached to wrapped face geotextile walls by the use of long bolts or thread bar anchors that are screwed into the geotextile earth retention structure. Although these methods are adequate to provide U.V. protection, corrosion of the bolts or metal anchors can reduce the life of the wall. The precast facing is also rarely attached accurately, so the resultant wall face may not be uniform in appearance.  
           [0012]    Another wall face that has been used for geotextile walls is the option of casting a poured-in-place concrete face over the geotextile textile wall. This approach can result in a uniform aesthetic face, but it does require extensive forming and the associated high field labor and material costs. These additional costs can make walls of this type less competitive than other conventional wall types.  
           [0013]    For wall locations where the retaining wall structure is located at the base of a hill or at the toe of an embankment, the cut or excavation required for the base of the wall may make the use of an MSE wall of any type impractical. Depending on the existing slope angle at the proposed wall site and in situ material of the sloping embankment, the excavation limits from the back of the cut may also be very large or require shoring in lieu of excavating massive amounts of material. For applications such as these, cast in place or tied back type retaining walls may be the current choice even though the cost of these walls exceeds the cost of typical MSE wall components.  
           [0014]    Cast-in-place, cantilever walls for these applications typically have an extended footing in front of the wall and a shear key. The cost of the shear key and the extension of the footing in front of the wall to offset the lack of the footing behind the wall (under the wall fill) results in a substantially more costly wall than would be the case for a standard configuration cast-in-place wall. By the same token, if a tied back or other top down type of wall is selected for the cut wall site (e.g., due to the high cost of wall excavation), the end result will be a wall with a much higher unit cost than for a typical MSE or cast in place wall.  
           [0015]    Another type of cast in place vertical cantilever wall application is for those walls along a channel or for bulkheads to act as erosion control structures along waterways or at the shore of other bodies of water. For channel applications where a vertical wall is required, if the area or right of way behind the proposed wall alignment is at a minimum, a front extension of the wall footing is required at the base of the wall. This situation, as for the previously described wall conditions, adds to the cost of the structure.  
           [0016]    Another method that has been used extensively for cantilever wall applications is the double tee wall system that was developed by Colorado Dept. of Transportation in the 1980&#39;s. For that design, double tee wall panels are placed on massive cast in place foundations to form a cantilever wall. The mechanism that is used to resist the overturning moments induced on the wall by the fill pressures is the extensive use of post tensioning rods. The rods are typically inserted through the tee stems of the double tee wall panels in the field and threaded into couplers cast into the wall foundation. To achieve the required accuracy for the placement of the couplers in the footing mandates, the use of special forming and highly skilled field personnel is required. Also, the installation of the post tensioning typically requires the use of special contractors in the field. As with the previous systems, should there be a void or incorrect application of grout at the connection point of the wall reinforcement the wall panel connection is subject to corrosion and premature failure.  
           [0017]    An additional precast wall system that simulates a conventional cast-in-place cantilever wall is disclosed in U.S. Pat. No. 4,572,711, issued on Feb. 19, 1986 issued to Benson et al. This system requires the use of a precast double tee attached to either a precast or cast-in-place flat footing slab. The implementation of this design has similar shortcomings as those stated for the CDOT tee wall system previously described. Since the footing shown for that post tensioned combination is a flat slab, the size and thickness of the footing is required to be massive, similar to the CDOT cast-in-place footing. Also, the installation of the post tensioning requires specialty contractors.  
           [0018]    In addition to the shortcomings stated for the above-mentioned systems, all of these products, with the exception of the Benson patent, require special forms for the production of the wall panels.  
           [0019]    There are currently numerous methods available to increase the stability of earthen embankments or to construct retaining walls. Retaining walls are generally constructed by excavating soil or rock at the desired location. Once the soil mass is excavated, the remaining soil mass is typically stabilized to prevent movement of that mass. Slope stability can be increased using soil nails. For example, a slope can be stabilized by drilling holes into an existing embankment, placing steel rods in those holes and then filling the holes with cementations grouts. By concurrently placing the steel rods and cement into an existing embankment, slope stability can be improved so that excavation can be completed in front of that stabilized embankment (i.e. in the plane perpendicular to the orientation of rods placed into the embankment), without risk of the embankment collapsing on the construction site. In another example, rods can also be placed into generally horizontally oriented shafts drilled into existing embankments. Following insertion of the rods into the shafts, concrete or high strength grout is injected into the shafts. The concrete or grout bonds the rods to the shaft, which results in a reinforced structural column within the soil mass of the embankment. There are currently many products that can be used to construct such ground anchored and or soil nailed structures.  
           [0020]    Anchored structures can also be used to increase soil stability in situ. Anchored structures are tensioned or loaded so that the load is placed on the face of the in situ soil mass. This face load, which is induced by anchor tensioning, holds the face of the anchors and the in situ material at a predetermined position. In contrast, soil nails are typically not loaded or tensioned when they are installed, but become loaded as the earth in front of the soil nailed structure is removed. A minor amount of movement of a soil nail in situ embankment is typically assumed in design. Movement of the embankment is a manifestation of the stabilizing effect of the soil nails replacing the buttressing effect of the existing in situ material in front of the soil nailed structure.  
           [0021]    Soil nails and anchors are prone to corrosion failures. For example, if the steel rods or steel strands are used as nails or anchors, they can corrode through contact with moisture and the soil. To minimize the effects of corrosion, products have been developed to protect metal rods or strands from corrosion. For example, the “Double Corrosion System” offered by the Dywidag-Systems International uses PVC pre-grouted sheathing over metal rods to provide a water tight barrier. Florida Wire and Cable, Inc., offers plastic sheaths over a flexible steel strand for use along soil anchors. Dywidag-Systems International also offers a “Dywidur” bar, which is a non-deformed fiberglass bar bolt. Such a bolt is suitable for use in highly corrosive soil, because it is resistant to corrosion. This bolt does not have significant deformation, so its use is limited in standard grout injection to providing a better bond to the drilled shaft. These products can be effective if installed properly and can offer extended life for the anchored structure.  
           [0022]    For anchored structures, corrosion protection is a major consideration. Because metal bars used in such structures are anchored, they are more prone to break under that tension. Therefore, metal bars used in such applications typically have double or triple corrosion requirements to ensure against failure of the anchored slope. Additional corrosion protection adds to the cost of currently available soil reinforcement for anchored slope stability projects.  
           [0023]    These and other corrosion-resistant products require proper installation to prevent damage to the corrosion-resistant coating material. The sites for such installations are generally uneven (e.g., mountainous or hilly), which requires heavy equipment. Such installation conditions increase the likelihood that damage might occur to the corrosion-resistant coating material. Because corrosion reduces the service length and load capacity of metal rods or cables, corrosion is a significant problem which limits the useful life of soil nailed or anchored structures.  
           [0024]    Another typical application where ground anchors, tie backs or soil nail earth retention structures are used is for the support of temporary site excavations for construction of buildings and other structures. For some locations, such as urban areas, it can be desirable to have the ability to remove or cut through the stabilized earthen wall utilizing tie back ground anchors or soil nails. Future utility placement or maintenance in the streets or other right-of-way areas behind the shoring may necessitate either the removal of or the cutting of trenches through the in situ reinforcement used as shoring. Currently the use of steel materials dominates the types of shoring used. Due to the high shear strength of steel tendons, steel rods, or steel threadbars cutting through the material is both costly and time consuming, resulting in expensive improvements in right-of-way areas behind excavation sites shoring.  
           [0025]    In view of these shortcomings of currently available devices for soil nailed or anchored structures, there is a need for soil nails and anchors that provide strength comparable to existing materials while providing improved resistance to corrosion and can be removed or cut if necessary. There is also a need for an economical MSE wall facing that utilizes corrosion resistant tensile inclusion members. There is an additional need for corrosion resistant tensionable rods that can be used to attach other precast concrete wall components to form retaining walls.  
         SUMMARY OF THE INVENTION  
         [0026]    The present invention provides devices to utilize corrosion-resistant, synthetic deformed bar (“SDB”) for use in soil stabilization structures, such as soil nailed or anchored structures, soil tensile inclusion members, or as tensionable tie or as connecting rods. As used herein, the term “bar” refers to a generally elongated synthetic structure which is a generally circular, ellipsoid, square, rectangular, polygonal or other regular or irregular cross section. A typical bar is composed of a synthetic, non-corrosive material, such as a resin. Suitable non-corrosive synthetic resins will include polyester, vinyl ester, epoxy and epoxy derivatives, urethane-modified vinyl ester, polyethylene terephthalate, recycled polyethylene terephthalate, and the like. Suitable resins can also include combination of any of these resins. The synthetic resin can be a complete fiber material, such as a combination of a synthetic resin and a fiber reinforcement. Suitable fiber reinforcements will include E-glass, S-glass, aramide fiber (e.g., Kevlar™), carbon fiber, ceramic reinforcement and the like and combinations of any of these. Suitable fiber composite materials are, for example PSI Fiberbar (Polystructures, Inc., Arkansas) or C-Bar (Marshall Industries). In some applications, the bar can be coated with a corrosion or moisture resistant material.  
           [0027]    The SDBs described in the present invention typically have adequate deformations for bonding to cementations grout (hereafter referred to as grout). As used herein, deformations can be corrugations, dimples, protrusions, and the like, on the circumference of the bar. Such deformations provide a larger surface for bonding of the bar surface to cement, concrete, grout or the like (hereafter generally referred to as “grout”). Such increased bonding area allows a stronger bond to be formed between the bar and the grout, thereby taking advantage of the load capacity of the bar. The deformations on the surface of the bar can optionally form a continuous repeating pattern on the surface of the bar. In such an embodiment, the deformation can have a generally relatively consistent spacing and depth (or height) from the bar&#39;s surface to provide a predictable field bonding characteristic. The deformations in the SDB also facilitate the connection of attachment devices, such as couplers to join SDB&#39;s to achieve longer length SDB&#39;s, as may be required for in situ soil reinforcement. The SDB can also have a flared end or a threaded end.  
           [0028]    Heretofore SDBs have been used extensively in lieu of standard steel reinforcement (rebar) for both cast in place and precast concrete structures. Prior to the use of SDBs, epoxy coated rebars were another conventional option that could be used for concrete structures placed within a corrosive environment such as for offshore structures. SDBs with an indefinite service life offer many advantages compared to both coated and uncoated steel rebar when used for concrete reinforcement for these types of applications.  
           [0029]    Attachment devices are provided to attach the bars to other structural components, which allows the load capacity of the bar to be transmitted to those other components. Attachment devices can be connected to a bar in a variety of ways. An attachment device or coupler can be connected to the bars during manufacture or at the construction site. A bonding agent is used to bond an attachment device to the SDB.  
           [0030]    An attachment device can be used to provide a means to transmit in situ earth loads at the face (“face load”) of the retained earthen structure to the in situ soil mass when the bars are used as ground anchors, soil nails or as tie backs. The tensile strength of the bars is then utilized to transfer the face load to the stable portion of the in situ soil mass. The length of the SDB is determined according to the soil anchor design to ensure that soil stability is enhanced. The length is also determined to ensure that the face load can be adequately carried by the SDB and the grout to the in situ soil mass. For some applications, anchor plates, rods or similar devices can be attached to the end of the SDB within the in situ soil mass to increase the loading capacity of the SDB. Attachment devices can also be attached to the portion of the SDB protruding from the face of the soil mass.  
           [0031]    Attachment devices on the face or protruding end of the SDB may be composed of a corrosion-resistant material that has adequate tensile strength to transmit any face loading to the in situ portion of the SDB. Such an attachment device can be a corrosion resistant metal, such as, for example, stainless steel, a similarly alloyed steel, a high strength aluminum, or the like. The attachment device can also be formed of a synthetic or conventional material, such as those disclosed above for the bar or can be formed of steel or numerous other steel or similar metal alloys. The preferred synthetic material will have a comparable tensile strength to the material of the SDB.  
           [0032]    For soil nailed, ground anchored, or tied back applications utilizing SDBs, a wall can be constructed by excavating a face on the soil mass. Such a face can be substantially vertical or can be at a lesser angle. Following initial face excavation, an exposed cut will exist. The SDBs are typically inserted into shafts placed in the in situ material per the site design. Grout is then injected into the shafts to secure the SDBs. The grout can be inserted according to conventional methods. Attachment devices are then attached to the exposed SDB ends. Alternatively, SDBs having previously bonded or otherwise connected, attachment devices can be placed in the shafts so that the attachment devices protrude from the face of the soil mass. Face reinforcement is then placed onto the exposed in situ soil face and attached to the exposed SDB bar ends or to the attachment devices on the bar ends. An encapsulation, such as field concrete, is then optionally applied over the face reinforcement. Specific designs may require face drainage materials and “shot crete” layers at various phases of construction.  
           [0033]    Soil anchor applications have similar construction phases as those of nailed structures except that the nail or anchor soil reinforcements are required to be tensioned after installation. Anchored applications typically require the use of threaded attachment devices to facilitate face tensioning with conventional jacking equipment. These attachment devices are connected as previously described. Tension can be applied to the bars at various phases of the excavation, according to the specific design criteria.  
           [0034]    For other “fill” retaining wall applications thin face wall panels attached to either SDB&#39;s as described in U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002 or by utilizing wire grid array mats are provided. Such walls can include for example an assembly of thin wall face panels that, with slight modifications to fit the wire grid array mats, are currently used for flat roof ballast paver applications. The grid pattern of the wires used for the wire grid array mats can be also manufactured to closely conform to the dimensions of precast ballast pavers as described by U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996 or the grids can alternatively match the dimensions of other thin wall face panels. In addition the wire grid array mat sections can be pre-bent to conform to various wall facing geometries. Although wire grid array mats are typically available utilizing standard steel for the wire grids for the retaining wall configurations described for the present invention, it is preferred, although not required, to utilize stainless steel, weathering steel, copper, aluminum or other metal alloys that are relatively unaffected by the deleterious affects of corrosion induced by placing wire grid array mats in contact with soil. Wire grid arrays can also utilize wires that are composed of a synthetic, non-corrosive material, such as a resin. Suitable non-corrosive synthetic resins will include polyester, vinyl ester, epoxy and epoxy derivatives, urethane-modified vinyl ester, polyethylene terephthalate, recycled polyethylene terephthalate, and the like. Suitable resins can also include combination of any of these resins. The synthetic resin can be a complete fiber material, such as a combination of a synthetic resin and a fiber reinforcement. Suitable fibers will include E-glass, S-glass, aramide fiber (e.g., Kevlar™), carbon fiber, ceramic reinforcement and the like and combinations of any of these. The wire shape can be round as is currently commercially available or wires can be of other common shapes i.e. square, rectangular or other common shapes with varying grid patterns in a wire grid array. Hereafter the term “wire”, when used herein, refers to the orthogonally oriented, generally circular shaped continuous flexible rod like members that, when bonded together at orthogonally oriented grid intersection points, form a grid array.  
           [0035]    For many of the embodiments of the present invention using thin face wall panels in combination with wire grid array mats, a portion of the wire grid is exposed to view on the face of the thin wall free panel. For other embodiments a portion of the wire grid in contact with the thin wall face panel is cancelled from view and is imbedded in edges of the panels. For configuration with either type of connection, that is in view or concealed, the wire grid array mats typically serve to stabilize and position the thin wall face panels at the face of an MSE wall. Typically the only earth loading imposed on a wire grid array mat is that portion contributed by the soil behind and adjacent to a thin wall face panel. Both the weight of the thin wall face panel and the minor earth loading imposed on the panel is supported by the wire gird array mats attached to the panel.  
           [0036]    For all embodiments the wire grid array mats have a rear portion that extends into a reinforced soil mass behind the exposed face of the wall. For walls of minor heights the rear portion of wire grid array mats can be sufficient to act as stabilizing tensile inclusion members to form the MSE wall. Taller walls utilize other common soil reinforcing materials such as welded wire mats, geogrid, or geotextile sheets placed within the soil mass. Flexible metal or synthetic sheets of these types can be used in combination with wire grid arrays for all embodiments of the present invention.  
           [0037]    The use of thin wall face panels offers many advantages compared to both concrete masonry unit (CMU) walls or for MSE walls formed with large concrete panels. Although thin wall face panels are comparatively light weight, i.e. approximately 15 pounds per panel for the ballast pavers described in U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996 they exhibit high strength due to the cross section and high compressive strength of the concrete mix used in paver manufacture. The lightweight and size of approximately 12″×16″×1.5″ facilitates ease of placement resulting in high production rates compared to that of the currently available CMU or panel systems. The substantially higher unit weight of the CMU and panel system face components typically requires lifting equipment to place theses face units. The lightweight of the thin wall facing panels facilitates fast and efficient hand placement of the panels. Additionally, standard wire grid array mats such as welded wire mats can be used for attachment to ballast pavers since the wire grid array spacing can approximate the width of ballast pavers. Different sizes and weights of panels are possible and are within the scope of the present invention as well as is the use of wire grid array mats of varying grid dimensions to correspond to panel sizes selected.  
           [0038]    The use of thin wall face panels not only allows for efficient placement with economical costs, but also walls can be configured in numerous wall facial appearances unattainable utilizing other current CMU or panel facing systems. For instance, in one embodiment of the present invention, thin wall face panels can be oriented with an outward batter for tiers of panels providing a planting space within the wall face. The resultant landscaping within the thin wall face panel MSE structure offers aesthetic features not available with other wall systems in current use.  
           [0039]    The ballast paver type thin wall face panel is manufactured in conventional high speed concrete roof tile machinery and the outer appearances of the pavers can be manufactured to have a similar appearance to roofing tiles. This colorful effect, along with various texture options, offer additional aesthetic features compared to the limited color and texture options attainable with CMU or panel systems in current use. For certain embodiments of the present invention ballast pavers can be arranged to match the appearance of the ship-lap effect of roofing tiles. This or other wall appearances can also either be constructed with an essentially vertical overall orientation or can be constructed with a batter appearing to lean off of a vertical plane. Either ballast pavers or other thin wall face panels or multiple panels can additionally be arranged in the wall face wherein a lower tier panel edge can utilized to support panels are adjacent upper tier. In certain instances the wire grid array mat may be exposed to view or placed within paver or thin wall face panels edges and the wires are not in view.  
           [0040]    Replacement of wall facing elements can be difficult and require substantial reconstruction with currently available CMU and panel MSE wall systems. For certain embodiments of the present invention, either with additional internal bracing or integral bracing of the wire grid array mats, efficient installation and replacement (if needed) of either pavers or other thin wall face panel types is facilitated. By bracing the earth loading of the MSE structure and thereby confining the MSE load to the wire mat, face panels can be removed and replaced over the life of any wall structure without disturbing the integrity of the MSE wall or adjacent thin wall face panels.  
           [0041]    The installation and or replacement of thin wall face panels is simply accomplished due to the flexible and resilient nature of the wire grid array mats. The exposed front section of the wire grid array mats can be slightly flexed as needed for panel installation and return to its original position after the paver or individual panel installation. By using a portion of the wire grid array to secure wall facing without additional attachment devices results in efficient placement or replacement of thin wall face panels.  
           [0042]    In another embodiment of the present invention thin face wall panels can be installed on opposite sides of wire grid array mats. This configuration has applications for sound or barrier walls typically used in urban areas of high traffic. Utilizing this configuration with the reverse batter (leaning out) wall face geometry allows for the option of planting within the wall face of the sound wall. The result of this internal landscape planting is both an aesthetically pleasing structure with additional sound dampening due to the landscaping.  
           [0043]    If a braced wall system is used for any of the thin wall face panel configurations described in the embodiments all or a portion of the MSE wall structure can be constructed prior to the installation of the thin wall face panels. This feature can offer wall construction site logistic advantages since the MSE wall construction can proceed in the field independent of thin wall face panel or ballast paver manufacture and delivery. Additionally the MSE wall can be utilized to surcharge or pre-compress weak or marginal foundation soils under the wall. This effect can induce any wall settlement and preclude future distress since wall foundation settlement, due to-the weight of the wall structure, occurs prior to rather than following wall construction.  
           [0044]    For certain retaining wall applications, wherein erosion control structures are utilized to strengthen and elevate existing flood control levees, the use of a “double-sided” precast wall can be desirable. A preferred method to form this type of assembly is by attaching two vertical double tee sections to each opposing end of a horizontal double tee section. When these units are structurally attached by either utilizing synthetic deformed bars, threadbars or steel cable stress strand, as described in U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002, a double-sided counterfort or double tee “H-brace” assembly is formed.  
           [0045]    Following assembly of “H-brace” tee units these precast assemblies can be used in combination with precast concrete wall panels placed between adjacent “H-brace” units in the field. The assembly formed can then be backfilled within the parallel walls formed by the panels placed on the flange extensions of the vertical tee components of the “H-brace” assembly of adjacent “H-brace assemblies.  
           [0046]    The system can either be used to create a new precast levee or floodwall or be used to elevate an existing earthen fill levee. For use to raise an existing levee, a “slot cut” method can be used that is similar to that excavation system that has been describe for other embodiments contained in U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002. A unique construction feature for elevating existing levees is the limited access attainable due to typically limiting work access from the top of the levee only. Since levee widths are typically narrow (under 30 feet), one-way traffic for equipment may also be mandated. Due to these site constraints, the use of the precast “Hbrace” is advantageous since little if any field concrete or additional fill is required which would entail numerous “two way” deliveries to implement. With the precast tee “H-brace” system an excavator can be the lead piece of equipment that cuts the slots, picks and sets the “Hbrace” units, places excavated fill within and around the “H-braces” and can be used to erect panels between the adjacent “H-brace” units. Although the lower portion of the T face panels can be at a lower elevation than either current or expected high water elevation the base units elevation is typically above the water surface elevation facilitating efficient placement of the units with an excavator. The excavator can typically be the lead piece of equipment on the levee with flatbeds delivering “H-brace” components to the access points of the excavator on the levee. The use of the “H-brace” system offers geotechnical advantages, construction ease, and cost savings compared to other conventional methods used for elevating levees.  
           [0047]    Typical concrete cantilever retaining walls or other conventional wall types, impact the wall foundation area inducing an increased vertical load in the in situ soil. Since levees are or will be subjected to flooding and may be in areas of silt or other low load-bearing capacity soil types, it is advantageous to use a floodwall system that has negligible impact on soil bearing capacity. Since the precast concrete “H-brace” assemblies are rigidly cross-tied together and because the unit weight of saturated soil and concrete are similar, a negligible load in induced on the in situ soil with the “H-brace” system. The vertical wall tees can additionally be extended down below the current or expected high water elevation so that the completed “Hbrace” structure has adequate scour protection. The cross-tied assembly also offers seismic advantages compared to a comparable structure utilizing either a conventional cantilever wall or sheet piling.  
           [0048]    One of the current approaches used to increase levee height is that of driving sheet piles into the in situ material on opposing sides of the levee. This is time consuming, disturbing construction, especially in urban areas due to continual high impact and vibration as a result of pile driving equipment. Additionally continual, on going corrosion protection can be required to be installed in order to extend the life of the steel sheet pile sections. Epoxy or other corrosion resistant coatings may be required to be applied to the pile sheets which adds to the cost of pile structures. Precast double tee “H-brace” components are not prone to the deleterious effects of corrosion and eliminate these extra costs associated with sheet piling.  
           [0049]    These and other objects, features, and advantages of the invention will be apparent from the following description of the invention as illustrated in the accompanying drawings. 
       
    
    
     BRIEF DECRIPTION OF THE DRAWINGS  
       [0050]    [0050]FIGS. 1 a - c  depict SDB test assemblies in an isometric, side and end views.  
         [0051]    [0051]FIGS. 2 a - b  depict a test end and load transfer of SDB test assemblies for ground anchor, tie back or soil nail applications.  
         [0052]    [0052]FIGS. 3 a - b  depict field open-ended SDB assemblies for soil nail applications in an isometric and sectional view.  
         [0053]    [0053]FIGS. 4 a - c  depict details of an assembled open-ended tube multiple SDB assembly in side and end views.  
         [0054]    [0054]FIGS. 5 a - c  depict test load transfer and force resolution of an open-ended tube multiple SDB assembly in side and end views.  
         [0055]    [0055]FIGS. 6 a - c  depict details of an assembled open-ended tube multiple SDB coupler.  
         [0056]    [0056]FIGS. 7 a - b  depict a schematic wall construction showing placement of wire grid arrays.  
         [0057]    [0057]FIG. 8 depicts a partially constructed tier of a reverse batter thin wall face panel MSE wall.  
         [0058]    [0058]FIGS. 9 a - b  depict modified precast ballast pavers used as thin wall face panels.  
         [0059]    [0059]FIG. 10 depicts a schematic wall construction showing reverse batter tiers of thin wall face panels attached to wire grid arrays.  
         [0060]    [0060]FIG. 11 depicts a partially constructed tier of a vertical tier thin wall face MSE wall.  
         [0061]    [0061]FIG. 12 depicts a sequential upper tier constructed over a first tier of a vertical tier thin wall face MSE wall.  
         [0062]    [0062]FIG. 13 depicts a schematic wall construction of a braced thin wall face panel MSE wall.  
         [0063]    [0063]FIGS. 14 a - d  depict vertical cross-sectional views of a reverse batter thin wall face panel MSE wall.  
         [0064]    [0064]FIGS. 15 a - d  depict typical details of both modified “grooved” ballast pavers and generic thin wall face panels and multiple thin wall face panel details.  
         [0065]    [0065]FIG. 16 depicts a partially constructed lower grooved ship-lap thin wall face panel MSE wall.  
         [0066]    [0066]FIG. 17 depicts a lower grooved ship-lap thin wall face panel MSE wall in a vertical section view.  
         [0067]    [0067]FIG. 18 depicts a partially constructed vertical tier thin wall face panel MSE wall with exposed wire grids.  
         [0068]    [0068]FIG. 19 depicts a partially constructed ship-lap thin wall face panel MSE wall with exposed wire grids.  
         [0069]    [0069]FIG. 20 depicts a partially constructed thin wall face panel barrier or sound wall.  
         [0070]    [0070]FIG. 21 depicts a substantially completed thin wall face panel barrier or sound wall.  
         [0071]    [0071]FIGS. 22 a - b  depict a schematic MSE wall construction utilizing integral braced wire grid arrays.  
         [0072]    [0072]FIGS. 23 a - c  depict vertical cross-sectional views of a reverse batter upper grooved thin wall face panel configuration utilizing integral braced wire grid arrays.  
         [0073]    [0073]FIGS. 160 a - b  depict isometric views of and “H-brace” assembly and an “H-brace” panel assembly.  
         [0074]    [0074]FIGS. 162 a - b  depict two views of an “H-brace” panel assembly. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0075]    Referring to FIG. 1, three views of a multiple SDB assembly utilizing an open-ended tube  16  confining a high compressive strength bonding medium are shown. View “a” in FIG. 1 shows a partial perspective view of a multiple SDB assembly  12 . Four SDBs  30  are shown encapsulated in a high compressive strength bonding medium  14 . An open-ended tube  16  of a rigid material such as steel, iron, aluminum or other metallic alloys or other rigid synthetic materials such as PVC or other plastic materials is shown confining and forming the boundary of the volume of the high compressive strength bonding medium  14 . Typical acceptable materials for high compressive strength bonding medium  14  are cementations grouts or other flowable materials such as synthetic epoxy grouts or other flowable materials that achieve a high compressive strength following the placement of the medium in a fluid state. A center sleeve  16  is shown placed with the high compressive strength bonding medium  14  placed along and parallel to the longitudinal axis of the multiple SDB assembly  12 . Materials suitable for the center sleeve  18  include steel or aluminum or other metallic alloys or high strength synthetic materials.  
         [0076]    A partial side view of an open-ended multiple SDB assembly  12  is shown in view “b” in FIG. 1. SDBs  30  are shown protruding from the Open-ended tube ring  16 . The cross-sectional shape of the open-ended tube  16  as shown is circular shaped but other cross-section shapes (as previously described) are acceptable and can be used in conformance with the present invention.  
         [0077]    View “c” in FIG. 1 shows a front end view of an open-ended tube multiple SDB assembly  12 . Four generally circular shaped SDBs  30  are shown embedded and encapsulated within a high compressive strength bonding medium  14 . Although four SDBs  30  are depicted, any number of SDBs  30  can be placed within an open-ended tube  16  and be in conformance with the present invention. The bonding medium thickness  20  is shown as the difference between the inner diameter of the open-ended tube  22  and the outer diameter of the center sleeve  24 . The bonding medium thickness  20  can be a variable dimension and is determined based on the strength characteristics of the specific bonding medium  14  and the strength of the SDBs  30 . The open-ended tube thickness  26  and the center sleeve thickness  28  are also variable depending on load applications of the open-ended tube multiple SDB assembly  12 .  
         [0078]    In FIG. 2 two views of an assembled open-ended tube multiple SDB assembly  32  and one view of a slotted load washer  34  are shown. View “a” in FIG. 2 shows details of the slotted load washer  34 . The outer diameter of a slotted load washer  36  can be less than the open-ended tube diameter  22  as indicated by the end view of the installed slotted load washer  36  as seen in view “c” in FIG. 2, although the diameter can be more or less. The slot depth  40  and slot width  38  are shown in view “a” and both dimensions can be more than the diameter of a SDB  30 . The number and locations of the slots  41  correspond to the number of SDBs  30  and desired location of SDBs  30  for a given open-ended tube multiple SDB assembly  12 . For specific applications the use of a standard washer (not shown) can be used in conformance with the present invention. The center circular void diameter  42  is slightly larger than the load application bar  44  shown in view “b” in FIG. 2.  
         [0079]    A side view of an assembled open-ended tube multiple SDB assembly  32  is shown in view “b” in FIG. 2. The slotted load washer  34  is positioned at the rear portion of the open-ended tube multiple SDB assembly  12 . The thickness of the slotted load washer  46  is sufficient to distribute the compressive forces induced on the slotted load washer  46  by the tensioning nut  48  shown threaded onto the exposed end of the tensioning bar  44 . The tensioning bar  44  is shown with continuous threads  47 . Shapes other than circular with or without threads including alternate mechanical connections other than the tensioning nut  48  can also be used to apply tension loading to the open-ended tube multiple SDB assembly and will be in conformance with the present invention.  
         [0080]    Now referring to view “c” in FIG. 2 an end view of an assembled open-ended tube multiple SDB assembly  12  as seen from the loaded rear end in depicted. The open-ended tube ring  16  and the slotted load washer  34  are shown with the tensioning nut  48  all centrally aligned along the longitudinal axis of the assembled open-ended tube multiple SDB assembly  12 .  
         [0081]    Two views of a field open-ended tube multiple SDB assembly  12  are shown in FIG. 1. View “a” in FIG. 1 shows a partial isometric view of a typical field open-ended tube multiple SDB assembly  12 . View “b” in FIG. 1 depicts a typical partial vertical cross-sectional view of a field open-ended tube multiple SDB assembly  12  in place in in situ soil  13 . The portion of in situ soil  13  shown would typically be the existing soil material of a soil nail or ground anchored structure placed into an existing slope. Retaining wall applications of this type are described in U.S. patent application Ser. No. 10/047,080 and are incorporated by reference herein.  
         [0082]    The partial isometric in view “a” in FIG. 1 shows a field open-ended tube  15  with face reinforcement bars  17  inserted through the field open-ended tube multiple SDB assembly  15  in an approximate orthogonal orientation. Bonding medium  14  is shown encapsulating SDBs  30 . The bonding medium  14  is shown encapsulated by the field open-ended tube end  19 . The volume of the bonding medium  14  closely corresponds to the inner volume capacity of the field open-ended tube end  19 .  
         [0083]    View “b” in FIG. 1 shows a typical field open-ended tube SDB assembly  15  encapsulated in grout  10  injected into the drilled hole  21  within the in situ soil  13 . Face reinforcements  17  are shown in front of field face reinforcement bars  23 . Field placed face concrete  25  is shown encapsulating the field face reinforcement bars  23 . The field open-ended tube SDB assembly  15  comprises the majority of SDB nail assemblies used for typical soil nail retaining wall applications.  
         [0084]    [0084]FIG. 2 shows two partial vertical cross-sectional views of a test open-ended tube SDB assembly  12  installed into in situ material  13 . Referring to view “a” in FIG. 1 a test open-ended tube SDB assembly  12  is shown with the SDBs  30  encapsulated with a grout plug  27  placed in the drilled shaft  21 . A test load  29  will typically be applied to the test open-ended tube SDB assembly  12  by various jacking methods in the field. The test load  29  is typically applied to a small percentage of soil nails or ground anchors to verify the typical bonding strength of the grout plug  27  to the in situ soil  13 . The test load  29  also may be used to verify the tensile capacity of the test open-ended tube SDB assembly  12 . The field open-ended tube SDB assemblies  10  are typically not tested.  
         [0085]    View “b” is shown in the lower portion of FIG. 2 and shows an installed test open-ended tube SDB assembly  12  following the application of test load  29 . Field face reinforcement bars  23  are shown placed behind face load plate  54 . Face nut  52  shown threaded into load bar  44  restraining the face load plate  54  transfers the earth loads induced on the field reinforcement bars  23  between adjacent SDB assemblies (not shown) to the load bar  44 . These loads are then transferred to either the field open-ended tube SDB assemblies  15  or the test open-ended tube assemblies  12  in a comparable manner so that earth loads are transferred to conventional steel thread bars or other soil anchor types in current use.  
         [0086]    Two load schematics of a test open-ended tube SDB assembly  12  are depicted in FIG. 3. View “a” in FIG. 3 depicts anchor resisting forces  37  aligned axially on SDBs  30 . The test load  29  is shown axially aligned on the load bar  44 . This is the equilibrium force condition that is also shown in view “a” in FIG. 2.  
         [0087]    The slotted load washer  34  is restrained from motion due to the application of test load  39  on the load bar  44  by the tensioning nut  48 . As the test load  29  is applied by jacking equipment, the slotted load washer  34  induces an open-ended tube uniform compressive load  56  equal to both the test load  29  and the resisting forces  37 . The test loading is therefore transferred to the bonding medium  14  by the slotted load washer  34 .  
         [0088]    A vertical cross-sectional view of the test open-ended tube assembly  12  is depicted in view “b” in FIG. 3. Bursting forces induced on the open-ended tube  16  and the outer sleeve  18  are outer radial forces  58  which are shown acting radially outward toward the open-ended tube  16  and the inner radial forces  60  which are depicted acting radially inward toward the center sleeve  18 . The SDBs  30  and the load bar  44  are equally loaded as described previously. The bonding medium  14  properties are determined based on the expected test load  29  and resisting forces  37  and the dimensions of the open-ended tube  16 . The bonding strength of the bonding medium  14  around the SDBs  30  is based on the bonding medium radial thickness  20 . The bonding medium  14  effectively transfers the axial test load  29  and the resisting forces  37  into the confines of the test open-ended tube  16  in an equilibrium condition.  
         [0089]    For some SDB  30  applications it may be necessary to combine standard length SDBs  30  to form longer bars. Details of an assembled open-ended tube multiple synthetic deformed bar coupler  33  are shown in FIG. 6. Examples of applications where longer SDBs  30  may be needed are for soil stabilization projects where SDBs  30  used as ground anchors, soil nails, or tie backs are longer lengths SDB&#39;s than the lengths of the SDB units that are normally shipped by conventional trucking means.  
         [0090]    View “a” in FIG. 6 shows an isometric view of an assembled open-ended tube multiple SDB bar coupler  33 . Although the open-ended tube  16  is shown with open end, closed ends such as plates or other means can be attached to the open-ended tube  16  if desired for SDB  30  alignment and if used will be in conformance with the present invention. The optional use of plates or that of other means to close the ends of the open-ended tube  16  can be included with any or all of the previously described embodiments without conflict with the present invention. As can be seen in view “a” in FIG. 6 the SDBs  30  extend away from and are essentially parallel to the longitudinal axis of the open-ended tube  16 . A bonding medium  14  is shown placed within the volume of the open-ended tube  16  encapsulating the portions of the SDBs  30  within the open-ended tube  16 .  
         [0091]    View “b” in FIG. 6 shows a partial side view of an assembled open-ended tube multiple SDB coupler  33 . SDBs  30  extend away from each end of the open-ended tube  16  and are held within the confines of the open-ended tube  16  by a bonding medium  14 .  
         [0092]    View “c” in FIG. 6 shows and end view of an assembled open-ended tube multiple SDB coupler  33 . Although four SDBs  30  are shown in this typical case, any number of SDBs  30  can be placed within the open-ended tube  16  and will conform to the present invention. The bonding medium  14  encapsulates the SDBs  30  as shown.  
         [0093]    Referring now to FIG. 7 two isometric views of wire grid array  74  placed between generally horizontally disposed layers of earth backfill  70 . View “a” in FIG. 7 shows a leveling course thickness  72  of suitable granular material such as sand or gravel placed at a constant predetermined grade over an exposed excavated in situ earth excavation plane (not shown). The wire grid arrays  74  are vertically displaced a predetermined fill lift height  78 . The vertical height of the earth backfill  70  corresponds to the lift height  78 . The wire grid array  74  shown in the uppermost portion of earth backfill  70  can be placed so that the transverse wires  86  and the longitudinal wires  82  are parallel to the lower wire grid array  74 .  
         [0094]    View “b” in FIG. 7 shows an upper partial earth backfill layer  76  with height roughly corresponding to lift height  78 . The upper grid layer  74  is shown extending beyond the upper partial fill layer  76  by a horizontal access displacement  84 .  
         [0095]    An isometric view of a partially completed thin wall face panel assembly  90  is depicted in FIG. 8. The thin wall face panels  80  are shown placed within the corresponding grid confines of the longitudinal wires  82  and transverse wire  86  of the vertically displaced wire grid arrays  74 . The thin wall face panel  80  with face widths  63  are shown in correspondence to the approximate spacing of the transverse wires  86 . The panel height  49  of the thin wall face panel  80  can be slightly greater than the lift height  78  as shown. The thin wall face panels&#39;  80  orientation is determined by the horizontal batter wire offset  92 . The thin wall face panels  80  are placed on the batter grid wire  68  and the face grid wire  94  as shown. Since the panel height  94  will be greater than the vertical lift  78  there is a lap distance  96  from both the face grid wire  94  and the batter grid wire  68  which is sufficient to position the thin wall face panels  80  behind the wire grids  74  separated as shown by the vertical left height  78 . The partial earth backfill layer  76  is shown partially covering the top wire grid array  74 . The weight of the partial earth backfill layer  76  stabilizes the wire grid array  74  and also subsequently stabilizes the thin wall face panel assembly  90 .  
         [0096]    [0096]FIG. 9 shows two partial isometric views of typical thin wall face panels that can be used for wall facing elements for the present invention. Panels similar to these are typically used for ballast paver applications as described by U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996. A typical thin wall face panel  80  is shown in view “a” in FIG. 9. The segments of wire grid arrays  74  with transverse grid spacing  69  are shown positioned at the top and bottom of the thin wall face panel  80 . The face width  63  of the thin wall face panel  80  can be equal to or slightly more or less than the transverse grid spacing  69  of the wire grid array  74 . Each thin wall face panel  80  can include a notched under shiplap edge  71  and an over shiplap edge  91  as shown. A grid bearing surface  65  is provided at the top and bottom of each notched under shiplap edge  71 . The upper notch  81  and the lower notch  85  are typical modifications that can be made to ballast pavers described in U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996 for their use as thin wall face panels in the present invention.  
         [0097]    View “b” in FIG. 9 shows a partial isometric of a slotted thin wall face panel  89  with a portion of wire grid arrays  74  at the upper and lower portion of the slotted thin wall face panel  89 . The notched under shiplap edge  79  extends beyond the face of the slotted thin wall face panel  89  as shown. An over shiplap edge  91  is shown on the opposite side of the slotted thin wall face panel  89  and the over shiplap edge  91  fits over the notched under shiplap edge  79  on the adjacent slotted thin wall face panel  89 . A similar edge condition and mating of adjacent thin wall face panels  80  is shown in view “a” in FIG. 8. The slotted under shiplap edge  79  is another typical modification that can be made on ballast pavers as described in U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996 for use as thin wall panels in the present invention.  
         [0098]    A grid bearing surface  65  is provided at both the upper and lower portions of the notched under shiplap edge  79 . Both the upper notch  81  and lower notch  84  have a width equal to the grid gap  73  which can be equal to or slightly greater than the diameter of the grid array  74  transverse wires  86 . Notched thin wall face panel  89  face width  63  can either be equal to, slightly greater or less than transverse grid spacing  69 .  
         [0099]    A partial isometric view of multi-tier reverse batter thin wall face panel assembly  100  is shown in FIG. 10. Face earth backfill  98  is shown placed behind the lower tier of thin wall face panels  80 . The upper tier of thin wall face panels  80  is shown positioned as described for the thin wall face panel assembly  90  previously described in FIG. 8.  
         [0100]    In FIG. 11 a partial isometric of a vertical tier thin wall face panel assembly  110  is depicted. The orientation of the base tier of the thin wall face panels  80  is shown in an essentially vertical orientation. The thin wall face panels  80  are shown placed against the batter grid wires  68  of each wire grid array  74 . The wire grid arrays  74  are shown as previously described vertically displaced by the lift height  78 .  
         [0101]    A subsequent upper tier of thin wall face panels  80  of a vertical tier thin wall face panel assembly  110  is shown in the partial isometric depicted in FIG. 12. Face earth backfill  98  is shown behind the base tier of thin wall face panels  80 . The upper tier of the thin wall face panels  80  is horizontally displaced from the front of the base tier thin wall face panels  80  are therefore in contact with and restrained from any outward horizontal displacement by the base tier thin wall face panels  80 . The batter of the wall face of the vertical tier thin wall face panel assembly  110  is equal to the panel thickness  83  which is also the horizontal offset as shown between the wire grid arrays  74 . This offset can be increased or decreased to change the overall wall face batter.  
         [0102]    A partial isometric of a braced reverse batter thin wall face panel assembly  114  is shown in FIG. 13. Thin wall face panels  80  are shown placed within wire grid arrays  74  as has been previously described. A wire grid array brace  112  is shown placed behind thin wall face panels  80 . The wire grid array brace  112 , shown in an essentially vertical orientation, is placed slightly behind the thin wall face panels  80 . Behind and adjacent to the wire grid array brace  112  a geotextile barrier  120  is included to prevent backfill particles from migrating out of the wire grid array brace  112 . The wire grid array brace  112  is held in an essentially vertical orientation by an angle strut wire  118 . By including the wire grid array brace  112  the wall backfill  70  placed behind the wire grid array brace  112  does not induce any significant earth wall loading on the thin wall panel face panels  80 . The partial earth backfill  76 , although shown in FIG. 12, is not required to maintain the position of the upper wire grid array  74  as would be required in the previously described embodiments since the upper wire grid array  74  may be held as well by the wire grid array brace  112 .  
         [0103]    A series of partial vertical cross-sections taken through a braced thin wall face panel assembly  114  during a typical wall building construction sequence is depicted in FIG. 14. View “a” shows an upper and lower wire grid array  74  including a wire grid array brace  112  supporting by an angle strut  118 . The wire grid arrays  74  extend in front of the wire grid array brace  112  by the installation horizontal offset  116 .  
         [0104]    View “b” in FIG. 14 shows the stabilizing effect of the weight of the earth fill  70 . Since the upper wire grid array  74  is restricted from movement behind the wire grid array brace  112  the portion of the wire grid array brace in the installation horizontal offset  116  can be displaced by the grid array flex  119  as shown.  
         [0105]    In view “c” in FIG. 14 a thin wall face panel  80  is shown placed with the bottom portion of the thin wall face panel  80  behind the horizontal offset longitudinal grid wire  88 . The upper portion of the thin wall face panel  80  is shown at the approximate in-place reverse batter orientation with the upper portion behind batter grid wire  68  with the wire grid array  74  displaced upward by the grid array  119 .  
         [0106]    The thin wall face panel  80  is shown in the in-place position in view “d” in FIG. 14. The batter grid wire  68  is now over the upper face of the thin wall face panel  80 . The flexible bending characteristics of the wire grid array  74  allows the wire grid array  74  to be displaced vertically and return to the original generally disposed horizontal planar position of the wire grid array  74  without causing a permanent deflection of the wire grid array  74 .  
         [0107]    Referring now to FIG. 15 numerous additional optional panel types are shown in partial isometric views. In view “a” in FIG. 15 an upper grooved thin wall face panel  87  is shown placed within partial grid arrays  74 . A grid groove  102  is shown at the upper edge of an upper grooved thin wall face panel  87 . The groove width  104  closely corresponds or exceeds the outer diameter of the batter grid wire  68 . The grid groove  102  extends down to the top of the notched under shiplap edge  71  as shown. The face width  63  closely corresponds to the transverse grid spacing  69  of the wire grid array  74 . The grid groove  102  is a typical modification of the ballast paver described in U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996.  
         [0108]    A partial isometric of a lower grooved thin wall face panel  64  is shown in view “b” in FIG. 15. Two partial wire grid arrays  74  are shown at the upper and lower edges of the lower grooved thin wall face panel  64 . A grid groove  102  is at the lower edge of the lower grooved thin wall face panel  64 . The grid groove  102  extends into the notched under shiplap edge  71  as shown. As with the previous descriptions the batter grid wire  68  is inserted into the grid groove  102  and the transverse grid wire spacing  69  closely corresponds to the face width  63  of the lower grooved thin wall face panel  64 . The effect of the vertically displaced grid arrays  74  is to maintain the batter orientation of the upper grooved thin wall face panel  87  or lower grooved thin wall face panel  64  without exposing the batter grid wire  68 . The grid groove  102  is a typical modification of the ballast paver described in U.S. Pat. No. 4,899,514 dated Feb. 13, 1990 and by U.S. Pat. No. 5,490,360 dated Feb. 13, 1996.  
         [0109]    In view “c” in FIG. 15 non-shiplap thin wall face panels  62  are depicted in a partial isometric view. The opposing edges of the non-shiplap thin wall face panel  62  are flat and adjacent vertical edges  61  abut as shown. The transverse wires  86  are shown placed in an upper notch  81  and a lower notch  85 . The transverse wires of the partially shown wire grid arrays  74  rest on the bearing surfaces  65 . The transverse grid spring  69  closely corresponds to the panel width  63  as shown.  
         [0110]    The manufacture of non-overlap thin wall face panels  62  does not require sophisticated forms. The use of the non-overlap thin wall face panels  62  requires upper slots  81  and lower slots  85  to allow for placement of the batter grid wire  68  over the face of the non-overlap thin wall face panel  62 . All other previously described embodiments can also be completed utilizing non-overlap thin wall face panels  62  and be in conformance with the current invention.  
         [0111]    In view “d” in FIG. 15 a multiple thin wall face panel  66  is shown in a partial isometric view. Partial wire grid arrays  74  are shown at the upper and lower portions of the multiple thin wall face panel  66 . The multiple panel width  126  is greater than the typical face width  63 . In addition two upper notches  81  and two lower slots  85  are shown in the respective edges of the multiple thin wall face panel  66 . Although two pairs of upper notches  81  and lower notches  85  are depicted, additional notches could be utilized depending on the chosen multiple panel width  126 . The use of the option to use the multiple thin wall face panel  66  of a wider width than standard panels previously described depends on the weight of the multiple thin wall face panel  66  and other economic factors which may result from the use of a larger multiple thin wall face panel  66  which eliminates numerous smaller typical face panels.  
         [0112]    The multiple thin wall face panel  66  can incorporate any of the geometric edge and grid connections previously described for the other thin wall face panel shapes previously described for the other embodiments of the present invention. In addition the use of the multiple thin wall face panel  66  can be utilized for any of the thin wall face panel assemblies previously described.  
         [0113]    An isometric view of a partially constructed grooved shiplap thin wall face panel assembly  108  is shown in FIG. 16. Two partially completed tiers utilizing lower grooved thin wall face panels  64  integrated with wire grid arrays  74  are shown in FIG. 16. A batter grid wire  68  is shown horizontally displaced from the lower grooved thin wall face panel  64  by a distance equal to the groove offset  106 . The transverse wires  86  are displaced into the notched under shiplap edge  71 . The engaged batter grid wire  68  is shown within the grid slot  102  in the lower edges of the grooved thin wall face panels  64 . By locating the batter wire  68  in the grid slot  102  as shown the batter grid wire  68  is not exposed to view with this embodiment of the present invention. Grid slots  102  can additionally be utilized in the previously described embodiments should the elimination of the exposed grid batter wire  88  be preferable for a specific embodiment application and be in conformance with the present invention.  
         [0114]    A vertical cross-sectional view of a grooved shiplap thin wall face panel assembly  108  is shown in FIG. 17. Wire grid arrays  74  are vertically displaced by the fill lift height  78 . Earth backfill layers  70  comprise the volume between the layers of grid arrays  74 . Lower grooved thin wall face panels  64  are shown arranged in an essential shiplap manner with the bottom portions of lower grooved thin wall face panels  64  overlapping the upper portions of the subsequent tier of the lower tier grooved thin wall face panels  64 . Face earth backfill  98  is placed through upper tiers wire grid arrays  74  to lower tier as shown. Efficient placement of the face earth backfill  98  is realized due to the relatively wide longitudinal spacing of the transverse wires  86  which roughly correspond to the face width  63  of the grooved thin wall face panels  87 . The placement of the face earth backfill  98  follows the installation of the subsequent lower tier grooved thin wall face panels  64 . Due to the fact that the wire grid arrays  74 , although flexible without fill layers  70 , the grids  74  are supported by the lower grooved thin wall face panels  64  and an earth backfill layer  70  allowing for efficient face earth backfill placement  98 . The generally horizontally disposed wire grid arrays  74  and the vertical or inclined thin wall face panels form a unique combination wherein the wire grid arrays  74  both support the weight of and maintain the orientation of the thin wall face panels with this and all embodiments of the present invention. This stable positioning of the thin wall face panels facilitates fill placement to the full height of the thin wall face panels at various stages of wall construction.  
         [0115]    The front face of the lower grooved thin wall face panels  64  bear on the fill face of the subsequent upper tier of the lower grooved thin wall face panels  64 . The lower portion of the upper subsequent tiers of the lower grooved thin wall face panels  64  fit over the batter grid wire  68  within the grid slot  102  in the lower edge of the grooved thin wall face panels  64 . Batter grid wire  68  bears on the bearing surface  65  within the grid slot  102  as shown. Lower grooved thin wall face panels  64  are inserted within wire grid arrays  74  in a similar manner to what has been previously described for the other types of the thin wall face panels  80 . Due to the flexibility of the exposed portion of the wire grid array  74  that extends in front of the partial fill layer  76 , the exposed wire grid array  74  can be flexed upward over the upper portion of the lower grooved thin wall face panel  64 . Upward movement of the wire grid array  74  facilitates placement of the grooved thin wall face panels  64  as shown. Since the wire grid array  74  is secured at the rear by the partial fill layer  76 , the exposed portion of the wire grid array  74  will return to the original, essentially horizontal orientation following the release of the wire array to the vertical displacement grid array flex  119 . The lower grooved thin wall face panel panels  64  tend to remain in the proper orientation as the lower grooved thin wall face panel  64  is subsequently placed due to the “springboard” effect of the partially confined wire grid arrays  74 . Each subsequent tier of lower grooved thin wall face panels  64  bears on the transverse wires  86  of the wire grid array  74  so that a portion of the weight of the fill tiers  70  are transferred to the wire grid  74 . Additionally the exposed or front tiers of the lower grooved thin wall face panels  64  are confined or restrained from any horizontal outward deflection due to the batter grid wire  68 . This and all previously described embodiments share this interaction with the wire grid arrays  74 .  
         [0116]    An isometric view of a thin wall face panel overlap wall assembly  122  is shown in FIG. 18. A base tier of thin wall face panels  80  are shown oriented away from a vertical plane due to the placement of the thin wall face panel  80  behind the panel offset grid wire  111 . The panel offset grid wire  111  is horizontally displaced from the batter grid wire  68  by a distance approximately equal to or slightly greater than the panel thickness  83  as shown. The wire grid array  74  is stable in a relatively horizontal plane due to the weight of the partial backfill layer  76 . The thin wall face panels  80  are installed within the wire grid arrays  74  in a similar manner to what has been previously described for the other embodiments of the present invention.  
         [0117]    A partially completed thin wall face panel overlap wall assembly  122  is depicted in the isometric view shown in FIG. 19. An upper subsequent tier of thin wall face panels  80  is shown in place over the base tier thin wall face panels  80  oriented as previously described in FIG. 16. The lower portion of the thin wall face panels  80  are in contact with and restrained from horizontal outward movement by the batter grid wire  68 . Face earth backfill  98  is also shown placed behind the base tier of thin wall face panel panels  80 . The face earth backfill  98  can be placed either following placement of the upper subsequent tier of thin wall face panels  80  or as the base tier is placed. The overall appearance of the thin wall face panel overlap assembly  122  is similar to the lower grooved thin wall face panel assembly  108  with the exception of the exposed batter grid wires  68  that are visible in the thin wall face panel overlap assembly  112 .  
         [0118]    Another embodiment utilizing thin wall face panels  80  is a sound/barrier wall configuration assembly  124 , which is shown partially constructed in FIG. 20 in an isometric view. Base tiers of thin wall face panels  80  are shown on opposing sides of wire grid arrays  74 . As with the previously described embodiments of the present invention, the grid arrays  74  are vertically displaced by the fill lift height  78 . The upper wire grid array  74  is stabilized by the effect of the weight of the partial fill layer  76 . The lower portion of the thin wall face panels  80  is placed against and on the inside of the batter grid wire  68  and the horizontal offset longitudinal grid wire  88 . The batter grid wire  68  and subsequently the upper portion of the thin wall face panels  80  are leaned out with a reverse batter equal to the horizontal batter offset  92 . The earth backfill layer  70  is confined on opposing sides of the wire grid arrays  74  by the thin wall face panels  80 .  
         [0119]    A vertical cross-sectional view of a sound/barrier wall configuration assembly  124  is depicted in FIG. 21. Four generally horizontal disposed tiers of adjacent thin wall face panels  80  are shown on opposite sides of wire grid arrays  74 . Earth backfill layers  70  of fill lift heights  78  are confined on opposite sides of wire grid arrays  74 . Thin wall face panels  80  are restrained from any horizontal outward movement by the longitudinal face grid wire  94  and the batter grid wires  68 . The batter face line  99  shown intersecting each batter face wire  88  is shown at an essential vertical orientation in FIG. 19. The wire grid arrays  74  can be fabricated to conform to any desired batter face line  99  as may be required for specific thin wall face panel  80  sound wall configuration assembly  124 .  
         [0120]    The horizontal batter offset  92  between the subsequent tiers of thin wall face panels  80  allows for the deposit of soil  115  placed on the exposed surface of earth backfill layers  70 . Another layer of soil  115  is shown above the top wire grid array  74 . The volumes of soil  115  placed as shown provide a root medium for landscape materials (not shown) to be planted between the tiers of thin wall face panels  80  within the face of the sound/barrier wall configuration assembly  124 . Although the thin wall face panels  80  are shown in a reverse batter orientation with an essential overall vertical batter face line  99 , any thin wall face panel  80  orientation of an arbitrary batter face line  99  can be selected for the sound/barrier wall configuration assembly  124  and conform to the present invention. Additionally any combination of the previously described embodiments of thin wall face panels wall assemblies can be utilized for specific sound barrier wall configuration assemblies  124 .  
         [0121]    Referring now to FIG. 22 an integral brace wire grid array thin wall face panel assembly  130  is shown in initial wall construction stages in a partial isometric views. Integral brace wire grid array  132  is shown stabilized by the weight of the partial backfill layer  76  of backfill lift height  78 . The integral brace wire grid array  132  is placed over a leveling course  72  is view “a” in FIG. 22.  
         [0122]    A subsequent upper tier of an integral braced wire grid array thin wall face panel assembly  130  is shown in the partial isometric depicted in view “b” in FIG. 22. The upper integral face wire grid array  130  is in place over the integral wire grid array  130  shown in view “a” in FIG. 22. A hinge pin  140  is shown partially inserted between both integral face wire grid arrays  132 . The stabilizing effect of the partial backfill  76  on the upper integral face wire grid array  132  holds both the upper and lower integral face wire grid array  132  due to the insertion of the hinge pin  140  between the integral face wire grid arrays  132 .  
         [0123]    Vertical cross-sectional views taken through the integral face wire grid array assembly  132  is shown in FIG. 23 during typical wall construction phases. Two typical integral face wire grid arrays  132  are shown connected with a hinge pin  140  separated vertically by fill lift height  78 . Each integral face wire grid array assembly  132  has a rear extension  134 , a face section  136  and a panel extension  138 .  
         [0124]    Additionally each integral face wire grid array  130  has a lower hinge bend  142  and an upper hinge bend  141  as shown. The deviation angle  144  compensates for the effect of the hinge pin diameter  146  (not shown) so that the overall face batter of the integral brace wire grid array thin wall face panel assembly  130  is not affected by the use of the hinge pin  140 . By placing the hinge pin  140  within the intersection of the lower hinge bend  142  and the upper hinge bend  144  of the integral brace wire grid array assemblies  132  the lower integral face wire grid array  132  is restrained from horizontal displacement by the shear resistance of the hinge pin  140  and the transverse face wires  148 .  
         [0125]    A geotextile reinforcement layer  150  is shown placed under the earth backfill layer  70  and behind the face section  136 . Face earth backfill  98  is shown in front of and in contact with the earth backfill layer  70  and behind and in contact with the face section  136 . Face earth backfill  98  can be placed as previously described for other embodiments of the present invention. The portion of the geotextile soil reinforcement under the earth backfill layer  70  is shown extending beyond the rear extension  134  of integral braced wire grid array  132 . The increased length or embedment depth of the geotextile soil reinforcement  150  acts to reinforce the earth backfill layers  70 . The reduced length of the rear extensions  134  is justified as the rear extension  134  is subjected to minimal thin wall face panel loading.  
         [0126]    Referring to view “c” in FIG. 23 an additional partial backfill layer  76  is shown placed over the completed upper earth backfill layer  70 . Upper grooved thin wall face panels  87  are shown placed in a reverse batter orientation with batter wire  68  placed in the grid groove  102 . Face earth backfill  98  placed in front of and in contact with the face section  136  and the rear portion of the upper grooved thin wall face panel  87  completes the base tier of the integral brace wire grid array thin wall face panel assembly  130 .  
         [0127]    The optional use of the integral face wire grid array assemblies  132  offers wall assembly advantages compared to the use of the wire grid array braces  112  due to the reduced number of components. The use of the integral face wire grid arrays  132  can be used with any of the previously described embodiments of the present invention.  
         [0128]    An isometric view of an “H-brace” assembly  202  is shown in view “b” and an “H-brace” panel assembly  200  is shown in view “a” in FIG. 160. Referring to view “a” in FIG. 160, and “H-brace” assembly  202  is shown placed on the top of an existing levee  204 . Standard height panels  206  are shown on the land side of the levee  204  and a top free board panel  208  is shown on the water side of the levee  204 . Standard height panels  206  are placed between two adjacent land side T face elements  214 . A free board top panel  208  is shown placed on a standard panel  206  placed between two adjacent water side face tee units  212 . The water side face T elements  212  are shown extending down at a lower elevation than the water surface elevation  210  into the water side of the levee than the land side face T elements  214  due to typical requirement to provide additional scour depth at the levee water side to minimize potential flow erosion at the base of the structure. The base elevation  211  of the base T element  216  is higher and usually “in the dry” compared to the water surface elevation  210 . Although two T stems are shown for both water side T face elements  212 , land side T face elements  214 , and base T elements  216  a single T stem section could be equally utilized for these elements.  
         [0129]    View “b” in FIG. 160 shows an isometric view of an “H-brace” assembly  202 . The water side face tee  212  and the land side face T element  214  are shown in an essentially vertical orientation at opposing ends of the generally horizontally disposed base T element  216 . The base T element  216  is typically attached to the water side face tee  212  and land side face T element  214  utilizing either synthetically deformed bars, steel stress strand cable or steel threadbars) as described in U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002.  
         [0130]    Referring now to FIG. 162, a plan view of an “H-brace” assembly  200  and a side sectional view of an “H-brace” panel assembly  202  is shown. A vertical cross sectional view of an “H-brace” assembly  202  is shown in view “a” in FIG. 162. The base T element  216  is shown placed on a leveling course  207  on top of the levee  204 . The excavation cut lines  220  show the outline of the excavation required prior to placing the “H-brace” assembly  202 . The water side face tee  212  and land side face T element  214  are attached to the base T element  216  as indicated by the attachment ducts  218 . Tensionable bars  217  are show within attachment ducts  218  placed within the base T element stems  215  and are parallel to the longitudinal axis of the base T element  216  and perpendicular to the flange of the water side face tee  212  and the land side face T element  214 . The water side face tee  212 , land side tee  214 , and base T element  216  are connected with tensionable bars  217  which are either synthetically deformed bars, steel stress strand, or threadbars placed in the attachment ducts  218  as described for the double tee counterfort assembly in U.S. patent application Ser. No. 10/047,080 filed on Jan. 14, 2002 and is incorporated by reference herein.  
         [0131]    A plan view of the “H-brace” panel assembly  200  is shown in view “b” FIG. 162. The water side face fee  212 , land side face T element  214 , and base T element  216  are attached as previously described. An optional fill access void  222  is shown in the base T element  216  to facilitate backfill placement between the excavation cut lines  220  and the land side face T element  214  and water side face tee  212 . Standard panels  206  and waterside panels  208  are shown placed against and bearing on flange extensions  224 .  
         [0132]    The preceding examples are provided to illustrate the invention but not to limit its scope. Other variants of the invention will be readily apparent to one of ordinary skill in the art and are encompassed by the appended claims. All publications, patents, and patent applications cited herein are hereby incorporated by reference for all purposes.