US20050013981A1

US20050013981A1 - Unitized structural reinforcement construct

Info

Publication number: US20050013981A1
Application number: US10/857,652
Authority: US
Inventors: Paul Schmidt; Gene Lamb; David Anderson; Nick Carter; Tom Dort
Original assignee: Polymer Group Inc
Current assignee: Avintiv Specialty Materials Inc
Priority date: 2003-05-30
Filing date: 2004-05-28
Publication date: 2005-01-20
Also published as: WO2004108626A1; EP1641725A1; JP2006526565A; MXPA05012930A

Abstract

The present invention relates to a fibrous and/or filamentary construct, which can be used in a mixture which can be cementitious, or an aggregate exhibiting adverse affects on the components therein, to provide supplemental and reinforcing strength upon setting, and more particularly, to a unitized construct which comprises a plurality of oriented reinforcing fibrous and/or filamentary components combined with a circumferential retaining element, said circumferential retaining element providing temporary retention of the oriented reinforcing components until such point the unitized substrate is incorporated and subjected to mechanical agitation during preparation of an aggregate compound. The unitized fibrous and/or filamentary construct is endowed with inherent and improved dispensability and dispersability of the associated reinforcing component into aggregates exhibiting adverse affects on the components therein, demonstrated by bituminous aggregates, such as asphalt, whereby the unitized fibrous and/or filamentary components are unaffected by the internal environmental conditions of the aggregate.

Description

TECHNICAL BACKGROUND

This invention relates to a fibrous and/or filamentary construct, which can be used in providing cementitious mixtures, or aggregates exhibiting adverse affects on the components therein, supplemental and reinforcing strength upon setting, and more particularly, to a unitized fibrous and/or filamentary construct which comprises a plurality of oriented reinforcing fibrous and/or filamentary components combined with a circumferential retaining element, said circumferential retaining element providing temporary retention of the oriented reinforcing components until such point the unitized substrate is incorporated and subjected to mechanical agitation during preparation of the mixture. The reinforcing fibrous components may comprise metallic or superabsorbent polymer fibrous components. Each fibrous and/or filamentary construct may comprise a plurality of fibrous or filamentary units, which in themselves, each comprise fibrous or filamentary components combined with a circumferential retaining element.

BACKGROUND OF THE INVENTION

Many proposals have been made to reinforce, strength, or otherwise beneficially alter the properties of cementitious and bituminous mixtures by applying and/or incorporating various types of fibrous components, including asbestos, glass, steel, as well as synthetic polymer fibers to aqueous based mixes prior to the curing of the mix. The types of polymer fibers in use or proposed for use include those composed of natural and synthetic composition.
As is evident in the prior art, individual fibrous components are well known in terms of their performance modifying attributes. Relatively large diameter fibers, for example, in excess of 40 to 60 microns in diameter, can be added to a cementitious mixture such as a wet concrete blend, dispersed in the blend by mechanical agitation, followed by pouring and curing of the concrete. Large diameter fibers serve to reinforce the concrete after it has been cured, by providing additional tensile strength and minimizing impact damage and crack propagation. Small diameter fibers, typically less than 30 to 40 microns in diameter, and having a relatively high surface area, are commonly added to concrete mixes in order to reduce the development of small cracks in the concrete during the curing period. The problem of crack development is known to occur as a result of uneven curing of the concrete.
The fibrous components used typically in the practice of reinforcing cementitious mixtures include specifically thermoplastic synthetic fibers of finite staple length, such as polypropylene staple fibers. Thermoplastic staple fibers are produced by a well known and economical melt spinning process, in which molten polymer is extruded through a die having a plurality of small openings to produce a tow of continuous thermoplastic filaments of a controlled diameter. The filaments are cooled and drawn or elongated to increase tensile strength. A size or finish is usually applied to the filaments, followed by drying and cutting into the desired length to provide bundles of individual fibers. The use of polypropylene fibers is desirable for several reasons, including low raw material cost, beneficial physical properties such as malleability, and the non-reactive chemical properties of the polymer in the adverse environments frequently encountered in cementitious mixtures (i.e. strongly alkaline pH).
While the functional performance of the reinforcing fibrous components, whether synthetic, metallic, natural, or a combination thereof, is beneficial, the means for the quantitative measurement, physical addition and homogenous distribution of the reinforcing fibrous components into a cementitious mixture is not without issue. Staple length fibers, as have been conventionally used, are provided in the same form as such are manufactured from the fiber formation line, which included agglomerates of various size and weight, tangles or knots of intermingled staple fibers, and numerous individual staple fibers that are in and of themselves prone to release randomly. Due to the variable and unpredictable form conventional reinforcing fibrous components have heretofore been provided for end-use consumption, such as at a construction work-site, the accurate and reproducible dosing of reinforcing fibrous component into sequential batches of cementitious mixtures has been dubious at best. Further complicating the actual utilization of the reinforcing fibrous components, numerous synthetic thermoplastic polymers used in the formation of suitable staple fibers are inherently hydrophobic in nature. As a result, difficulties can arise in obtaining a uniform dispersion and blending of the reinforcing fibrous component throughout hydrous cementitious mixtures using conventional mixing equipment.
Prior attempts to address the issue described have focused on the use of binding agents. U.S. Pat. No. 5,399,195, incorporated herein by reference, discloses the addition of small amounts of fine (less than 30 microns) polymer fibers to concrete. During production, the filaments are treated with a topical wetting agent. After the filaments are chopped into staple-length fibers, the wetting agent holds or binds the staple fibers together in the form of micro-bundles. The micro-bundles remain relatively stable during handling, and when the fibers are added to the concrete mix, the wetting agent promotes dispersion of the fibers. U.S. Pat. No. 6,258,159, also incorporated herein by reference, attempts to address the forming of micro-bundles of fibers by incorporation of binding agents into the staple fibers themselves during the melt-extrusion process.
The use of binding agents, whether internal or externally applied, while improving in-part issues inherent of individual staple fibers, such practices have not obviated such problems as random agglomerate size, and further, the use of binding agents has introduced additional problems. Most notably, the corresponding performance of the binding agent is based upon application of the binding agent to the reinforcement fibrous components such that the binding agent is both uniformly applied to the majority of the fibers so as to obtain equivalency within the batch, and that no excess binding agent is introduced as such will adversely effect the ability of the reinforcement fibrous components to disengage and distribute homogeneously. One other determent encountered in the use of binding agents is that air is often entrained within the micro-bundles upon application and agglomeration of the staple fibers. When such micro-bundles are subjected to mechanical mixing, the entrained air is released as a foam, a foam that reasonably compromises the ability of the cementitious mixture to cure uniformly.
As is evident in the industry, a unmet need exists for a means of introducing reinforcing fibrous and/or filamentary components into an aggregate which may exhibit adverse affects on the components therein, such that the reinforcing fibrous and/or filamentary components exhibit the attributes of uniform and predictable presentation for use, ability to be homogenous distributed during mechanical agitation, and does not introduce an adverse chemical agent which can compromise the performance of the resulting aggregate.

SUMMARY OF THE INVENTION

The present invention relates to a fibrous and/or filamentary construct, which can be used in a mixture which can be cementitious, or an aggregate exhibiting adverse affects on the components therein, to provide supplemental and reinforcing strength upon setting, and more particularly, to a unitized construct which comprises a plurality of oriented reinforcing fibrous and/or filamentary components combined with a circumferential retaining element, said circumferential retaining element providing temporary retention of the oriented reinforcing components until such point the unitized substrate is incorporated and subjected to mechanical agitation during preparation of an aggregate compound. The unitized fibrous and/or filamentary construct is endowed with inherent and improved dispensability and dispersability of the associated reinforcing component into aggregates exhibiting adverse affects on the components therein, demonstrated by bituminous aggregates, such as asphalt, whereby the unitized fibrous and/or filamentary components are unaffected by the internal environmental conditions of the aggregate.
The unitized construct is endowed with inherent and improved dispersability and dispensability of the associated reinforcing components into organic or inorganic cementitious matrices, such as concrete, mortar, plastic, etc. The reinforcing component of the present unitized construct may comprise metallic or superabsorbent polymer fibrous components of finite staple or infinite length. The present fibrous and/or filamentary construct may be configured as a compound construct, which comprises a plurality of fibrous or filamentary units, which in themselves, each comprise the oriented reinforcing fibrous or filamentary components combined with one or more of the circumferential retaining elements.
The unitized fibrous and/or filamentary construct of the present invention is formed from two or more reinforcing fibrous and/or filamentary components of finite or infinite length, essentially parallel in orientation, and a circumferential retaining element. The compositions of the reinforcing fibrous and/or filamentary component is selected from the group consisting of synthetic polymers, natural polymers, metallic fibers, and the combinations thereof, and are not necessarily of the same polymeric composition, denier, finite staple length, or functionality. The compositions of the metallic reinforcing fibrous components are selected from the group consisting of ferrous and non-ferrous metals, alloys thereof, including a combination thereof. The circumferential retaining element describes a route about the combined two or more essentially parallel reinforcing fibrous components, thereby maintaining both the combination and essentially parallel orientation of the reinforcing components. Once formed, the circumferential retaining element aids in maintaining the integrity of the unitized fibrous and/or filamentary construct, and the reinforcing fibrous and/or filamentary components therein, for purposes of shipment, measurement, and dosing into an aggregate compound. Upon mechanical agitation of the unitized construct in an aggregate, which may exhibit adverse affects on the components therein, the circumferential retaining element is disrupted, allowing for the homogenous release, distribution, and dispersement of the reinforcing fibrous and/or filamentary components into the overall mixture without deteriorating due to extreme environmental conditions.
The circumferential retaining element is selected from suitable materials, such as thermoplastic, thermoset and soluble resins, which are subject to mechanical failure when a corresponding stress and/or solvency threshold is exceeded. Various geometries may be employed in the application of the circumferential retaining element, including without limitation, continuous or discontinuous filaments, ribbons, or sheets, which circumscribe the combined, essentially parallel reinforcing fibrous and/or filamentary components. Optionally, the reinforcing fibrous and/or filamentary components may be orientated in a fashion other than parallel. It is within the purview of the present invention that the composition of the circumferential retaining elements and of one or more of the reinforcing components need not necessarily be the same. Further, the reinforcing components may comprise more than one similar or dissimilar circumferential retaining element.
As noted, the present unitized construct may include superabsorbent polymer fibrous components. Upon introduction to the cementitious mixture, the one or more incorporated superabsorbent polymers begin to expand due to the moisture presence. Further, once exposed to mechanical agitation, the circumferential retaining element of the unitized fibrous construct is disrupted, releasing the tension within the fibrous construct caused by the expanded super absorbent polymer. The release of the tension build-up within the fibrous construct assists with distribution and disbursement of the reinforcing fibrous component into the overall cementitious mixture.
It should be noted that the reinforcing fibrous and/or filamentary components, as well as the resulting unitized fibrous and/or filamentary constructs, can be treated with performance modifying additives, such as represented by the topical application of a material flow-enhancing lubricant. Further, temporary binding agents, including water-soluble chemistries such as polyvinyl alcohol, can be used in conjunction with the circumferential binding element.
Upon final formation of the unitized fibrous and/or filamentary constructs, the constructs can be readily packaged through an automatic packaging system or containerized in bulk. The latter packaging allows for a quantity of unitized constructs to being accurately and reproducibly augured, scooped or blended into an aggregate compound at a mixing station, for example, through an automated gravimetric dispensing system.
Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a photograph of a representative unitized fibrous construct as formed in accordance with the present invention, approximate dimensions are an overall circumference of 25 mm and a length of 18 mm;
FIG. 2 is a photomicrograph of the same unitized fibrous construct as shown in FIG. 1, wherein the plurality of reinforcing fibrous components and the single circumferential retaining element are more specifically depicted;
FIG. 3 is a photograph of a representative unitized fibrous construct as formed in accordance with the present invention; and
FIG. 4 is a photomicrograph of the same unitized fibrous construct as shown in FIG. 3, wherein the plurality of reinforcing fibrous components and the single circumferential retaining element are more specifically depicted.

DETAILED DESCRIPTION

While the present invention is susceptible of embodiment in various forms, hereinafter is described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.
Finite staple length fibers are routinely used as a reinforcement means in aggregates which may exhibit adverse affects on the components therein, so as to render a corresponding cured construct incorporating such fibers more resistant to structural defect and failure. Specific environments which are understood to adversely affect aggregate components are those of temporary or continuous: extreme temperature (herein defined as being temperatures greater than 125° C. or less than 0° C.) variations in pH levels (herein defined as being pH levels greater than 10 and less than 4) and/or abrasiveness. Due to difficulties encountered in the actual handling and homogenous incorporation of the finite staple length fibers experienced in preparing an aggregate compound, the present invention is directed to a means for facilitating such preparation without the introduction of potentially problematic binding agents.
A unitized fibrous and/or filamentary construct which comprises a plurality of oriented reinforcing components combined with a circumferential retaining element, is formed such that said circumferential retaining element provide temporary retention of the oriented reinforcing components until such point the unitized substrate is incorporated and subjected to mechanical agitation during preparation of an aggregate exhibiting adverse affects on the components therein. The unitized fibrous and/or filamentary construct is endowed with inherent and improved dispensability and dispersability of the associated reinforcing fibrous and/or filamentary components into aggregate exhibiting adverse affects on the components therein, without having a delirious affect on the incorporated reinforcing components.
The unitized construct of the present invention is formed from two or more reinforcing fibrous and/or filamentary components of finite or infinite length and essentially parallel orientation, wherein the composition of such fibers and/or filaments is selected from the group consisting of synthetic polymers, natural polymers, and the combinations thereof. Preferably, the composition of the reinforcing fibers and/or filaments is selected from the synthetic polymers including, without limitation, thermoplastic and thermoset polymers. A particularly preferred embodiment of the present invention is directed to reinforcing fibers and/or filaments comprising polyolefin thermoplastic resins. It is within the purview of the present invention that the individual reinforcing components as incorporated in the unitized construct need not necessarily be of the same polymeric composition, denier, finite staple length, or functionality. Optionally, a portion of the reinforcing fibrous and/or filamentary components or all of the reinforcing components may be placed under tension by means of twisting the reinforcing components or by other means. Placing tension on some or all of the reinforcing fibrous components causes the fibrous and/or filamentary components to burst or pop upon mechanical agitation, which enhances the fiber and/or filament distribution within an aggregate compound.
The present unitized construct may comprise metallic fibrous components of either finite staple or infinite length, selected from the group consisting of ferrous metals, non-ferrous metals, alloys of such metals, and the combinations thereof. Such a unitized metallic fibrous construct may also include synthetic polymers, and combinations thereof. The present unitized construct may also comprise superabsorbent polymer fibrous reinforcing components of either finite staple or infinite length.
The unitized fibrous and/or filamentary construct further includes a circumferential retaining element. The circumferential retaining element describes a route about the combined two or more essentially parallel reinforcing fibrous and/or filamentary components, thereby maintaining both the combination and essentially parallel orientation of the reinforcing fibrous components. Once formed, the circumferential retaining element aids in maintaining the integrity of the unitized construct, and the reinforcing fibrous and/or filamentary components therein, for purposes of shipment, measurement, and dosing into a aggregate exhibiting adverse affects on the components therein. Upon mechanical agitation, and optionally exposure to appropriate solvents, of the unitized construct in an aggregate compound, the circumferential retaining element is disrupted, allowing for the homogenous release, distribution and dispersement of the reinforcing fibrous and/or filamentary components into the overall mixture without deteriorating due to extreme environmental conditions.
The circumferential retaining element is selected from suitable materials, such as thermoplastic, thermoset and soluble resins, which are subject to mechanical failure when a corresponding stress and/or solvency threshold is exceeded. Various geometries may be employed in the application of the circumferential retaining element, including without limitation, continuous or discontinuous filaments, ribbons, or sheets, which circumscribe the combined, essentially parallel reinforcing fibrous and/or filamentary components. It is within the purview of the present invention that the composition of the circumferential retaining elements and of one or more of the reinforcing components need not necessarily be the same. Further, more than one circumferential retaining element may circumscribe the circumference of the reinforcing fibrous and/or filamentary components, which may not necessarily be the same geometry or composition.
The reinforcing fibrous components can be retained by two thin circumferential retaining elements in a double helix wrapping technique, whereby two circumferential retaining elements criss-cross back and forth about the circumference of the fibrous components. It is within the purview of the present invention that the composition of the circumferential retaining element and of one or more of the reinforcing fibrous components need not necessarily be the same.
Preferably, the circumferential retaining element circumscribes no more than 80% of the total surface area of the unitized fibrous and/or filamentary construct; more preferably circumscribes no more than 50% of the total surface area of the unitized fibrous and/or filamentary construct; and most preferably circumscribes no more than 30% of the total surface area of the unitized fibrous and/or filamentary construct. Limiting the circumferential retaining element serves to expose the oriented reinforcing fibrous and/or filamentary components within the unitized constructs to the external environment. In addition, the exposure of the fibrous and/or filamentary components allows for more effective disruption of the unified construct when subjected to mechanical or solvent disruption.
A number of suitable methodologies exist for the formation of unitized fibrous and/or filamentary constructs in accordance with the present invention. A preferred, though non-limiting, method is taught in part by U.S. Pat. No. 4,228,641, incorporated herein by reference, wherein a twine comprised of a core bundle of synthetic monofilaments is circumscribed by a synthetic material in a thin band form spirally wound about the monofilaments. It has been found by the inventors of the present invention that by practice of the '641 method, with subsequent and repeated scission of the continuous twine construct at or between each iteration of the spiral winding that finite length unitized fibrous constructs are formed which are suitable for practice in light of the present invention.
The dimensions of the unitized fibrous and/or filamentary construct is defined in terms of the overall circumference, as based on the quantity and relative denier of the individual reinforcing components, and of length, as based on the greatest finite staple length of the cumulative combination of reinforcing components. Suitable overall circumferences and lengths of unitized fibrous and/or filamentary constructs formed in accordance with the present invention may reasonably range from 3 mm to 150 mm and from 8 mm to 100 mm, respectively. In a presently preferred embodiment for standard practices, unitized fibrous constructs exhibit an overall diameter of between 3 mm and 30 mm and lengths of between 12 mm and 50 mm may be utilized.
In accordance with the present invention, the unitized fibrous and/or filamentary components may be of infinite lengths, so as to provide a fibrous and/or filamentary construct in a continuous form. Such a formation allows the continuous unitized reinforcing fibrous and/or filamentary components to be available in a continuous form and packaged in a continuous lap or roll formation. Further, the continuous unitized fibrous and/or filamentary construct may comprise a series of segmented perforations or weakened points along the continuous formation so that the desired portion may be selected and detracted from the remainder of the roll form.
The reinforcing construct of the present invention can be formed as a compound construct, including plural units each comprising two or more reinforcing components, and a retaining element. In a first form, the compound unitized fibrous of filamentary construct of the present invention is formed from two or more fibrous or filamentary units of reinforcing fibrous or filamentary components, wherein the components are of finite staple lengths and essentially parallel orientation and circumscribed by one or more circumferential retaining elements. The compound unitized fibrous or filamentary construct, which is comprised of two or more fibrous or filamentary units of finite staple length reinforcing fibrous or filamentary components, is also unitized by one or more circumferential retaining elements, so as to form a compound unitized fibrous or filamentary construct.
In a second form, the compound unitized fibrous or filamentary construct of the present invention is formed from two or more fibrous or filamentary units of reinforcing fibrous or filamentary components, wherein the components are of infinite lengths and essentially parallel orientation and circumscribed by one or more circumferential retaining elements. The compound unitized fibrous or filamentary construct, which is comprised of two or more fibrous of filamentary units of infinite length reinforcing fibrous of filamentary components, is also unitized by one or more circumferential retaining elements, so as to form a compound unitized fibrous or filamentary construct.
In a third form, the compound unitized fibrous and/or filamentary construct of the present invention is formed from two or more fibrous and filamentary units of reinforcing fibrous and filamentary components, wherein the components are of finite staple length or of infinite lengths and essentially parallel orientation and circumscribed by one or more circumferential retaining elements. In this embodiment, the compound unitized fibrous and filamentary construct may comprise fibrous and filamentary components of similar or dissimilar materials. Further, the fibrous and filamentary components may enhance the cementitious mix in a similar or dissimilar manner, wherein one component may enhance the strength of the cementitious mix and the other component may enhance the aesthetics of the cementitious mix. The compositions of the reinforcing fibrous or filamentary components is selected from the group consisting of filaments exhibit an overall diameter of between 3 mm and 30 mm and lengths of between 12 mm and 50 mm may be utilized.
In accordance with the present invention, the reinforcing fibrous or filamentary components may be of infinite length, wherein the reinforcing fibrous components are combined in an essentially parallel orientation, whereby one or more circumferential retaining elements circumscribes about the overall circumference of the continuous reinforcing fibrous or filamentary components.
Upon final formation of the compound unitized fibrous or filamentary constructs, the constructs can be readily formed into easy-to-handle structures to enhance durability of the construct, improve handling and packaging of the construct, as well as improve distribution of the construct within a cementitious mixture, such structures include, but are not limited to small briquettes or nuggets, or larger blocks or bricks, or even larger cinder block structures. further, the compound unitized fibrous or filamentary construct structures may comprise one or more modifying additives or agents embedded within the structure such as in tablet or packet form, packed through an automatic packaging system and containerized in bulk. The latter packaging allows for a quantity of unitized fibrous constructs to being accurately and reproducibly augured, scooped or blended into a cementitious mixture at a mixing station, for example, through an automated gravimetric dispensing system.
It should be noted that the reinforcing components, as well as the resulting unitized constructs, can be treated with performance modifying additives, such as represented by the topical application of a material flow-enhancing lubricant and temporary binding agents, such as water-soluble chemistries.
Upon final formation of the unitized fibrous and/or filamentary constructs, the constructs can be readily packaged through an automatic packaging system or containerized in bulk. The latter packaging allows for a defined quantity of unitized constructs to being accurately and reproducibly augured, scooped or blended into an aggregate compound at mixing station, through an automated gravimetric dispensing system.
From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.

Claims

1. A method of improving the properties of a mixture, wherein said method comprises the steps of:

a. providing a mixture;

b. providing unitized fibrous and/or filamentary constructs, each of said unitized fibrous and/or filamentary constructs being comprised of:

i. two or more reinforcing fibrous and/or filamentary components;

ii. a circumferential retaining element;

iii. wherein said reinforcing fibrous and/or filamentary components are combined in an essentially parallel orientation and said circumferential retaining element circumscribes about an overall circumference described by said combined and essentially parallel reinforcing fibrous and/or filamentary components;

c. adding into said mixture a quantity of said unitized fibrous and/or filamentary constructs so as to form a blend; and

d. mechanically agitating said blend so as to disrupt said circumferential retaining elements and disperse said reinforcing fibrous and/or filamentary components into said mixture.

2. A method as in claim 1, wherein said fibrous and/or filamentary unitized constructs exhibit an overall circumference of between about 3 mm to 150 mm.

3. A method as in claim 2, wherein said unitized fibrous and/or filamentary constructs exhibit an overall circumference of between about 3 mm to 30 mm.

4. A method as in claim 1, wherein said unitized fibrous and/or filamentary constructs exhibit a length of between about 8 mm to 100 mm.

5. A method as in claim 4, wherein said unitized fibrous and/or filamentary constructs exhibit a length of between about 12 mm to 50 mm.

6. A method as in claim 1, wherein said mixture is a bituminous aggregate at an elevated temperature.

7. A method as in claim 2, wherein said mixture is a cementitious mixture, and said fibrous and/or filamentary constructs comprise metallic fibrous components exhibiting a finite staple length.

8. A method as in claim 1, wherein said mixture is a cementitious mixture, and said fibrous and/or filamentary constructs comprise metallic fibrous components of infinite length.

9. A method as in claim 1, wherein said mixture is a cementitious mixture, and said fibrous and/or filamentary constructs comprise superabsorbent polymer fibrous compounds exhibiting a finite staple length.

10. A method as in claim 1, wherein said mixture is a cementitious mixture, and said fibrous and/or filamentary constructs comprise superabsorbent polymer fibrous components exhibiting an infinite length.

11. A method as in claim 1, wherein each of said fibrous and/or filamentary constructs comprises two or more fibrous or filamentary units each comprising two or more of said reinforcing fibrous and/or filamentary components.

12. A method as in claim 1, wherein each of said reinforcing fibrous and/or filamentary components exhibits a finite staple length.

13. A structural reinforcement for a mixture comprising unitized fibrous and/or filamentary constructs, each of said unitized fibrous and/or filamentary constructs being comprised of two or more reinforcing fibrous and/or filamentary components and one or more circumferential retaining elements, wherein said reinforcing fibrous and/or filamentary components are combined in an essentially parallel orientation and said circumferential retaining element circumscribes about an overall circumference described by said combined and essentially parallel reinforcing fibrous and/or filamentary components.

14. A structural reinforcement for a mixture in claim 7, wherein said circumferential retaining element circumscribes no more than 80% of the total surface area of said unitized fibrous and/or filamentary constructs.

15. A structural reinforcement as in claim 13, wherein said reinforcing fibrous and/or filamentary components comprise metallic fibrous components.

16. A structural reinforcement as in claim 15, wherein said metallic fibrous components exhibit a finite staple length.

17. A structural reinforcement as in claim 13, wherein said reinforcing fibrous and/or filamentary components comprise superabsorbent polymer fibrous components.

18. A structural reinforcement as in claim 17, wherein said superabsorbent polymer fibrous components exhibit a finite staple length.

19. A structural reinforcement as in claim 13, wherein each of said fibrous and/or filamentary constructs comprises two or more fibrous or filamentary units each comprising two or more of said reinforcing fibrous and/or filamentary components to provide compound reinforcing constructs.

20. A structural reinforcement as in claim 19, wherein each of said reinforcing fibrous and/or filamentary components exhibits a finite staple length.