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Title:
SOUND WALL WITH ULTRA-LIGHTWEIGHT FOAMED GLASS AGGREGATES
Document Type and Number:
WIPO Patent Application WO/2022/164984
Kind Code:
A1
Abstract:
Systems and methods are disclosed for a highway sound wall system comprising a sound wall panel assembly filled with loose foam glass aggregates. The highway sound wall may further comprise a pair of spaced apart vertical members. The vertical members may be H- beams having a flange portion and a body portion. The highway sound wall may further comprise a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly. Each of the vertical members may have at least one stop block attached to the flange portion and at least one stop block attached to the body portion. At least one vertical edge of the mesh members may have an attached bar which engages both stop blocks. The sound wall may be temporary or permanent.

Inventors:
FILSHILL ARCHIBALD STEWART (US)
MCGRATH THOMAS LIAM (US)
Application Number:
PCT/US2022/014028
Publication Date:
August 04, 2022
Filing Date:
January 27, 2022
Export Citation:
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Assignee:
AEROAGGREGATES OF NORTH AMERICA LLC (US)
International Classes:
E01F8/00; E02D29/02; E04C3/30; E04H17/16
Attorney, Agent or Firm:
HUBBARD, Brian J. (US)
Download PDF:
Claims:
Claims:

1. A highway sound wall system, comprising: a sound wall panel assembly filled with loose particles of foamed glass aggregates.

2. The highway sound wall of claim 1 , further comprising a pair of spaced apart vertical members.

3. The highway sound wall of claim 2, wherein the vertical members are H-beams having a flange portion and a body portion.

4. The highway sound wall of claim 2 or 3, further comprising a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly.

5. The highway sound wall of claim 2 or 3, wherein each of the vertical members has at least one attached stop block.

6. The highway sound wall of claim 5, further comprising a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly, wherein at least one vertical edge of the mesh members has an attached bar which engages the at least one stop block.

7. The highway sound wall of claim 3, wherein each of the vertical members has at least one stop block attached to the flange portion and at least one stop block attached to the body portion.

8. The highway sound wall of claim 7, further comprising further comprising a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly, wherein at least one vertical edge of the mesh members has an attached bar which engages both stop blocks.

9. The highway sound wall of claim 1 , wherein the sound wall panel assembly is greater than 6 feet tall.

10. The highway sound wall of claim 1 , wherein the sound wall panel assembly is greater than 8 feet tall.

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11. The highway sound wall of claim 1 , wherein the sound wall panel assembly is greater than 10 feet tall.

12. The highway sound wall of claim 1 , wherein the sound wall panel assembly is greater than 4 feet wide.

13. The highway sound wall of claim 1 , wherein the sound wall panel assembly is greater than 6 feet wide.

14. A method of constructing a highway sound wall system, comprising: providing a pair of spaced apart soldier beams; trapping a pair of mesh panels between the soldier beams; and filling space defined between the mesh panels and soldier beams with loose particles of foamed glass aggregates.

15. The method of claim 14, further comprising placing the mesh panels into place from above the soldier beams.

16. A method for connecting a pair of spaced apart soldier beams to a pair of retaining grids, comprising: providing a stop block on a flange portion of each of the soldier beams; providing a bar along a lateral edge of each of the retaining grids; and sliding the retaining grids into place from above, such that the stop blocks engage the bars, trapping the retaining grids in place.

17. The method of claim 16, further comprising providing a stop block on a body portion of each of the soldier beams for engaging the bar on a different face from a face of the bar engaged by the stop block on the flange portion of each of the soldier beams.

18. A method of constructing a highway sound wall system, comprising: providing a pair of spaced apart soldier beams; trapping a pair of retaining grids between the soldier beams, wherein trapping comprises: providing a stop block on a flange portion of each of the soldier beams; providing a bar along a lateral edge of each of the retaining grids; and sliding the retaining grids into place from above, such that the stop blocks engage the bars, trapping the retaining grids in place; and filling space defined between the retaining grids and soldier beams with loose particles of foamed glass aggregates.

19. The method of claim 18, wherein the retaining grids are hot-dipped galvanized mesh panels.

20. The method of claim 18, wherein the foamed glass aggregates are prepared from recycled glass.

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Description:
SOUND WALL WITH ULTRA-LIGHTWEIGHT FOAMED GLASS AGGREGATES

CROSS-REFERENCE TO RLATED APPLICATIONS

[0001] This application claims the benefit of provisional U.S patent application Serial No. 63/143,195, filed January 29, 2021, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Sound walls are large structures placed beside highways to abate noise. Their efficacy in this regard has been called into question, as they tend to reflect noise as opposed to absorbing noise. Sound walls are conventionally made of concrete and may stand 12-16 feet tall, sometimes taller. FIG.1 depicts a conventional sound wall system 100. A series of concrete panels 102, having optional rails 103 are disposed between posts 104 and anchored posts 106. A concrete panel 102 might typically weigh about 70-155 Ib/cf (pounds per cubic foot, sometimes referred to in industry as pounds per square foot "psf"). Panels vary in size. For example, typical examples would include from about 2 to about 8 feet wide and about 8 to about 12 feet tall. In the case of a 4'x1 O', one foot thick, 73 psf concrete panel, the weight will be nearly 3,000 pounds. Panels must be either cast in place or prefabricated and hoisted into place with a crane or other heavy machinery. If prefabricated, it is understood that a concrete panel 102 is not adjustable to fit between the posts (e.g., 104 and/or 106), thereby requiring tight tolerances for post spacing.

[0003] The posts 104 may be connectors, or alternatively, may be replaced with anchored posts 106. In most cases, each of the posts 104 and 106 may require a foundation. At the least, the anchored posts 106 require a foundation to support the tremendous weight of the concrete panels, as well as shear forces exhibited by winds or vehicle collisions with the wall system 100. Caissons 108 are used to support the anchored posts 106, and in some cases, a portion 106a of the anchored posts 106 is disposed in the caisson 108 and back-filled with concrete. As noted above, placement of the caissons 108 and anchored posts 106 is critical, as the concrete panels 102 are not adjustable in width. As can be appreciated, installation of such concrete panels is a large construction project, with commensurate costs due to the involved forces and required precision.

[0004] In some cases, such as vehicle collisions with the wall system 100, a concrete panel 102 can become damaged or develop a structural fault 110. In such cases, replacement of the concrete panel is a major undertaking, requiring demolition, re-installation with a crane, etc. Accordingly, what is needed is a sound wall system that is lighter weight, adjustable, and easy to install or repair. It would also be highly beneficial if the sound wall absorbed at least a portion of the ambient sound rather than reflected the sound. SUMMARY

[0005] Systems and methods are disclosed for a highway sound wall system comprising a sound wall panel assembly filled with loose foam glass aggregates. The highway sound wall may further comprise a pair of spaced apart vertical members. The vertical members may be H-beams having a flange portion and a body portion. The highway sound wall may further comprise a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly. Each of the vertical members may have at least one attached stop block. At least one vertical edge of the mesh members may have an attached bar which engages the at least one stop block. Each of the vertical members may have at least one stop block attached to the flange portion and at least one stop block attached to the body portion. At least one vertical edge of the mesh members may have an attached bar which engages both stop blocks. The sound wall may be temporary or permanent.

[0006] Systems and methods are disclosed for constructing a highway sound wall system, comprising providing a pair of spaced apart soldier beams, trapping a pair of mesh panels between the soldier beams, and filling space defined between the mesh panels and soldier beams with loose foam glass aggregates. The mesh panels may be lifted into place from above the soldier beams.

[0007] Systems and methods are disclosed for connecting a pair of spaced apart soldier beams to a pair of retaining grids, comprising providing a stop block on a flange portion of each of the soldier beams, providing a bar along a lateral edge of each of the retaining grids, and sliding the retaining grids into place from above, such that the stop blocks engage the bars, trapping the retaining grids in place. A stop block may also be provided on a body portion of each of the soldier beams for engaging the bar on a different face from a face of the bar engaged by the stop block on the flange portion of each of the soldier beams.

[0008] Systems and methods are disclosed for constructing a highway sound wall system, comprising providing a pair of spaced apart soldier beams, trapping a pair of retaining grids between the soldier beams, wherein trapping comprises providing a stop block on a flange portion of each of the soldier beams, providing a bar along a lateral edge of each of the retaining grids, and sliding the retaining grids into place from above, such that the stop blocks engage the bars, trapping the retaining grids in place, and filling space defined between the retaining grids and soldier beams with loose particles of foamed glass aggregates.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 depicts a perspective view of a conventional highway sound wall according to the prior art.

[0010] FIG. 2 depicts a front view of a sound wall according to the present disclosure incorporating ultra-lightweight foamed glass aggregates (such as UL-FGA™ foamed glass aggregates). [0011] FIG. 3 depicts foam glass aggregates, such as UL-FGA™ foamed glass aggregates.

[0012] FIG. 4 depicts a top sectional view of a vertical member of FIG. 2 along a line 4-4.

[0013] FIG. 5 depicts a perspective view of a moveable sound wall according to another embodiment.

DETAILED DESCRIPTION

[001 ] Systems and methods are disclosed for a highway sound wall system comprising a sound wall panel assembly filled with loose foam glass aggregates. The highway sound wall may further comprise a pair of spaced apart vertical members. The vertical members may be H-beams having a flange portion and a body portion. The highway sound wall may further comprise a pair of spaced apart mesh members extending between and retained within the vertical members, thereby forming the sound wall panel assembly. Each of the vertical members may have at least one attached stop block. At least one vertical edge of the mesh members may have an attached bar which engages the at least one stop block. Each of the vertical members may have at least one stop block attached to the flange portion and at least one stop block attached to the body portion. At least one vertical edge of the mesh members may have an attached bar which engages both stop blocks. The sound wall may be temporary or permanent.

[0015] Systems and methods are disclosed for constructing a highway sound wall system, comprising providing a pair of spaced apart soldier beams, trapping a pair of mesh panels between the soldier beams, and filling space defined between the mesh panels and soldier beams with loose foam glass aggregates. The mesh panels may be lifted into place from above the soldier beams.

[0016] Systems and methods are disclosed connecting a pair of spaced apart soldier beams to a pair of retaining grids, comprising providing a stop block on a flange portion of each of the soldier beams, providing a bar along a lateral edge of each of the retaining grids, and sliding the retaining grids into place from above, such that the stop blocks engage the bars, trapping the retaining grids in place. A stop block may also be provided on a body portion of each of the soldier beams for engaging the bar on a different face from a face of the bar engaged by the stop block on the flange portion of each of the soldier beams. [0017] Foam glass aggregates are an inert, stable, and environmentally friendly substrate. Typically, to form foam glass aggregates, recycled glass is cleaned, ground, mixed with a foaming agent, heated, and allowed to fragment from temperature shock. The resulting aggregates are cellular, with a relatively low bulk density, but relatively high durability. Foam glass aggregates have many uses, for example, as a lightweight fill for construction applications, vehicle arrestor beds, building insulation, etc. However, since foam glass aggregates provide an important economic driver for glass recycling, finding new uses and applications for foam glass aggregates is extremely desirable.

[0018] FIG. 2 depicts a highway sound wall system 200. The system 200 comprises at least two vertical members 202. The vertical member 202 may be a soldier pile. In a preferred embodiment, the vertical member 202 is a steel H-pile (or H-beam), however, other vertical members are contemplated by this disclosure, including steel tubular structures or approved support posts for supporting a wall. The vertical member 202 may be a hot-dipped galvanized H-pile. The vertical member 202 may be driven in place, such as by a pile driver, or may be placed in a suitable hole and back-filled with concrete, or may have another suitable foundation for the load. The highway sound wall system 200 may be from about 8 feet tall to about 12 feet tall, preferably about 10 feet tall. The vertical members 202 may be from about 4 feet apart to about 10 feet apart, preferably about 6 feet apart to about 8 feet apart. As will be described, vertical members 202 need not be spaced an identical distance apart.

[0019] A sound wall panel assembly 204 is disposed between two vertical members 202. The sound wall panel assembly 204 may be restrained or entrapped between the two vertical members 202, such that it is secured from falling. The sound wall panel assembly 204 comprises a pair of retaining grids 206 (only the front is visible in FIG. 2) with a layer of loose foam glass aggregates (not depicted). The foam glass aggregates are preferably ultra-lightweight foamed glass aggregates, and more preferably, UL-FGA™ foamed glass aggregates procured from AERO AGGREGATES OF NORTH AMERICA, Eddystone, PA. The foamed glass aggregates are disposed between the retaining grids. UL-FGA™ foamed glass aggregates weigh about 20lb/cf (or psf), which is approximately 80 % lighter than gravel. As can be appreciated, this greatly reduces the support requirements for vertical members 202. Moreover, a layer of UL-FGA™ foamed glass aggregates possesses considerable sound insulation properties. It is understood that foamed glass aggregates refers to loose particles or fragments of foamed glass. As such, they are easily handled in a manner similar to gravel, but without the weight and with better properties, as will be described. Many sizes for the sound wall panel assembly 204 are contemplated. For example, the sound wall panel assembly may be greater than about 6 feet tall, greater than about 8 feet tall, and greater than about 10 feet tall. For example, the sound wall panel assembly may be greater than about 2 feet wide, greater than about 4 feet wide, and greater than about 6 feet wide. Engineering requirements and regulatory stipulations may dictate size of the sound wall.

[0020] The retaining grids 206 may be metal, preferably a coated, galvanized, anodized, or other treated metal designed for long term outdoor exposure. Such materials may be determined by federal regulation or other regulatory requirements for construction projects. Spacing for the grid size of the retaining grids 206 may be a 1 -inch by 1 -inch, for example a steel mesh panel, for example, a hot-dipped galvanized mesh panel. In any event, it is understood that the mesh size of the retaining grids 206 is small enough to retain the foamed glass aggregates.

[0021] The sound wall panel assembly 204 may be constructed on site, for example, after the two vertical members 202 are installed, the retaining grids 206 may be lifted into place, requiring no connections on site. The retaining grids 206 may secured to the two vertical members 202, preferably, as described with respect to FIG. 4, thereby defining a space between the grids. Foamed glass aggregates are placed in the space defined between the retaining grids 206. Together, the retaining grids 206 can be said to cooperate to define a cage for the foamed glass aggregates. Examples of methods of placing foamed glass aggregates (e.g., loose particles or fragments of foamed glass aggregates) include prefabricating cages (comprising retaining grids 206) with foamed glass aggregates in the space or filling cages in the field with foamed glass aggregates once the wall is constructed. A layer of foamed glass aggregates may be placed as loose particles or fragments and then compacted. The space between the retaining grids 206 (e.g., cage depth/thickness) may be preferably about 6 inches to about 12 inches. [0022] Advantageously, vertical members 202 need not be spaced an identical distance apart. For example, a sound wall panel assembly 204' is substantially similar to the sound wall panel assembly 204, but covers a greater distance between two vertical members 202. A sound wall panel assembly 204" is substantially similar to the sound wall panel assembly 204', but covers a slightly greater distance between two vertical members 202. Variation necessary to afford structural stability for the span and height is contemplated. It is also understood that even if the retaining grids 206 are prefabricated (thus requiring careful spacing of the vertical members 202), the cost of the system still will be greatly reduced compared to conventional systems due to the significantly lower weight (and therefore loads) involved.

[0023] In one embodiment, the layer of foamed glass aggregates does not require a foundation and may be directly in contact with the soil. An optional liner may be disposed between the foamed glass aggregates and the soil layer. The optional liner may be a permeable liner, a semi-permeable liner, or an impermeable liner depending on the site and application. Those skilled in the geosynthetics, geo- environmental engineering, or construction can readily appreciate if a liner is desirable. Suitable impermeable liners include those made from reinforced polyethylene, reinforced polypropylene, thermoplastic olefin, ethylene propylene diene monomer, polyvinyl chloride, isobutylene isoprene, butyl rubber, etc. Alternatively, a knee wall may be installed and the foamed glass aggregates placed on top of the knee wall.

[0024] An optional port 208 may be provided in the sound wall panel assembly 204, 204', or 204"

(depicted). The port 208 may be installed on site, e.g., before the foamed glass aggregates fill is added, by securing the port in the space defined between the retaining grids. The port 208 may be for drainage and/or to provide a passageway for small animals (for example, in environmentally sensitive areas) the necessary openings in the retaining grids 206 being made.

[0025] FIG. 3 depicts UL-FGA™ foamed glass aggregates, given the reference numeral 300, for use in the present sound wall systems. As can been seen in FIG. 3, UL-FGA™ foamed glass aggregates particles are quite angular, and as a result, the interaction of the various UL-FGA™ foamed glass aggregates particles defines voids 302 between the particles. Suitable UL-FGA™ foamed glass aggregates may be procured from AERO AGGREGATES OF NORTH AMERICA, Eddystone, PA. The UL- FGA™ foamed glass aggregates may be prepared from a recycled glass cullet. The UL-FGA™ foamed glass aggregates may be prepared from a sodo-calic glass. As UL-FGA™ foamed glass aggregates are made up of silica, they may be considered a natural material for regulatory purposes. As UL-FGA™ foamed glass aggregates are made from recycled glass, they may be considered environmentally friendly. Alternatively, UL-FGA™ foamed glass aggregates may be prepared from waste glass (e.g., byproduct from glass manufacture) or other glass particles, for example, glass that is other than post-consumer recycled glass. UL-FGA™ foamed glass aggregates properties include low unit weight, low thermal conductivity, high strength, non- absorbent, non-toxic, non-leachable, chemically stable, impervious to UV degradation, freeze/thaw stable, and fireproof. The UL-FGA™ foamed glass aggregates may have a particle size of about 5mm to about 80mm, preferably, about 10mm to about 60mm. Upon installation, the UL-FGA™ foamed glass aggregates may have a bulk density of about 120 kg/m 3 to about 400 kg/m 3 , preferably about 170 kg/m 3 to about 290 kg/m 3 , and more preferably about 200 kg/m 3 to about 240 kg/m 3 .

[0026] Returning to FIG. 2, in the context of the highway sound wall system 200, certain UL-FGA™ foamed glass aggregates properties are particularly beneficial, such as, for example, UL-FGA™ foamed glass aggregates are highly frictional (e.g., once compacted, UL-FGA™ foamed glass aggregates are unlikely to shift with time), UL-FGA™ foamed glass aggregates are non-leaching, UL-FGA™ foamed glass aggregates are chemically inert (e.g., safe), UL-FGA™ foamed glass aggregates are rot-resistant (in fact, UL-FGA™ foamed glass aggregates are rot proof), UL-FGA™ foamed glass aggregates are nonflammable, UL-FGA™ foamed glass aggregates are durable (e.g., UL-FGA™ foamed glass aggregates does not degrade when used in this application), and UL-FGA™ foamed glass aggregates are rodent resistant (e.g., resists burrowing animals and insects).

[0027] In a first example, the UL-FGA™ foamed glass aggregates may have an open cell structure. Open cell foamed glass is produced by using a different foaming agent than that used for closed cell foamed glass. The foaming agent for open cell reacts faster in the heating process and creates interconnections between the air bubbles which allow water to be absorbed into the aggregates. The UL- FGA™ foamed glass aggregates with an open cell structure may, in particular, have pores to support growth of microbes and bacteria. In a second example, the UL-FGA™ foamed glass aggregates may have a closed cell structure. It is understood that UL-FGA™ foamed glass aggregates, as used in this disclosure, comprises both open cell or closed cell structures unless specified as one or the other.

[0028] UL-FGA™ foamed glass aggregates can be submerged underwater with no deleterious effects. As can be appreciated, a sound wall comprising UL-FGA™ foamed glass aggregates combined with water treatment media could take part in improving roadside water quality or otherwise improving the roadside environment. For example, UL-FGA™ foamed glass aggregates (e.g., either open cell UL-FGA™ foamed glass aggregates or closed cell UL-FGA™ foamed glass aggregates) may be combined with water treatment media (such as, for example steel slag, calcium carbonates, organoclays, etc.) that removes phosphates, nitrates, and/or hydrocarbons. The water treatment media may be a coating, dusting, or otherwise applied to a surface of the UL-FGA™ foamed glass aggregates. In a preferred embodiment for wet environments, the LIL-FGA™ foamed glass aggregates are a closed cell LIL-FGA™ foamed glass aggregates having organoclay deposited on its surface.

[0029] T urning now to FIG. 4, an attachment assembly 400 is provided for connecting the retaining grids 206 to the vertical member 202. Each retaining grid 206 comprises a plurality of horizontal bars 401 and a plurality of vertical bars 402. The plurality of horizontal bars 401 and the plurality of vertical bars 402 may cooperate to form a steel mesh. The gauge of the bars 401, 402 may be at least 1/8 inch, preferably at least 3/16 inch. A layer of foamed glass aggregates 404 is disposed in the space defined between the retaining grids 206. The pair of spaced apart retaining grids may comprise a cage.

[0030] The retaining grid 206 further comprises a rectangular bar 406 welded to the horizontal bars 401. The bar 406 may be continuous and may be a steel bar (e.g., galvanized). The retaining grid 206 may be lifted into place so that it is disposed relatively interior to a flange portion of the vertical member 202. The bar 406 may engage the flange portion of the vertical member 202 to prevent outward movement of the grid 206.

[0031] Stop blocks 408 are attached to the vertical member 202. For example, the stop blocks 408 may be continuous or segmented steel bars welded to the inside of the flange portion of the vertical member 202. The stop blocks 408 engage the bar 406 to prevent lateral movement or sagging of the grid 206.

[0032] Optionally, a second set of stop blocks 410 may be attached to the vertical member 202. For example, the stop blocks 410 may be continuous or segmented steel bars welded to the inside of the body portion of the vertical member 202. In this embodiment, the stop blocks 410 hold the grid 206 in place while the foamed glass aggregates are being added.

[0033] In another embodiment, the grids are cut to size on site to accommodate variation in spacing between the vertical members.

[0034] In another embodiment, a method of repairing a damaged conventional sound wall (such as in FIG. 1) is provided. The damaged concrete panel is demolished and two vertical members 202 (FIG. 2) and a sound wall panel assembly 204 (FIG. 2) are placed in the resulting opening. The attachment assembly 400 (FIG. 4) is used for connecting the retaining grids 206 to the vertical member 202.

[0035] FIG. 5 depicts a perspective view of a moveable sound wall 500 according to another embodiment. A plurality of posts are disposed in a base (e.g., such as a Jersey barrier or a U-shaped concrete trough). Steel mesh is secured to the posts and foamed glass aggregates are placed within the enclosure (not depicted). The foamed glass aggregates may be from about 6 inches to about 18 inches and provide sound absorption. The moveable sound wall 500 may be from about two feet high to about six feet high and may be from about six feet long to about ten feet long. Multiple moveable sound walls 500 may be placed together end-wise to create a temporary sound wall, for example, beside roads, construction, concerts, amusement parks, sporting events, etc. [0036] In yet another embodiment, the sound walls according to this disclosure may be attached to buildings, such as to afford building cladding that absorbs sound. A layer of foamed glass aggregates behind steel mesh is free draining (thus placing no water pressure on the building) and extremely lightweight. The attachment assembly of FIG. 4 may be applied to this embodiment as well, for example to secure a plurality of mesh panels inside taller vertical members.

EXAMPLES

Example 1

[0037] Recycled glass cullet is cleaned, ground to less than 150 micrometers (US Standard sieve size No. 100), mixed with a foaming agent (e.g., for open cell foamed glass aggregates, a carbonate foaming agent; for closed cell foamed glass aggregates, a silicon carbide foaming agent) in a blending unit, heated, and allowed to fragment from temperature shock. The resulting foamed glass aggregates are cellular.

After sample preparation, the initial moisture content is measured following ASTM D2216 (2010), grain size distributions are determined following ASTM C136/136M (2006) and the initial bulk density is measured following ASTM C127 (2012a) on the foamed glass aggregates. The average moisture content is determined to be 1.06% (initially, the moisture content will be lower (although if exposed to moisture the foamed glass aggregates can hold up to 10% by volume on its surface)) and the average bulk density is determined to be 227.2 kg/m3 (14.2 pcf). Sieve analyses are performed following the dry sieving method on the foamed glass aggregates. Particle size ranges from 10 to 30 mm (0.39 to 1.18 in) but is a very uniformly graded material.

Example 2

[0038] Recycled glass cullet is cleaned, ground, mixed with a foaming agent, heated, and allowed to fragment from temperature shock. The resulting foamed glass aggregates are cellular (foaming creates a thin wall of glass around each gas bubble). By volume, the foamed glass aggregates are approximately 92% gas bubbles and 8% glass. The water content (per ASTM D 2216) of the foamed glass aggregates will change with time due to the cellular nature of the material.