Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
SEAL MEMBER, SYSTEM AND METHOD OF SEALING A MICRO TRENCH
Document Type and Number:
WIPO Patent Application WO/2023/147041
Kind Code:
A1
Abstract:
A seal member has a T-shape with radial protrusions configured to seat within a micro trench to form a water tight, damage-resistant seal. In some aspects, the seal may be removed to allow for subsequent access to utilities installed therein. The seal has a suitable compressive strength to support the trench walls without damaging the pavement and accommodates expansion and contraction of the micro trench and pavement caused by changes in temperature. Systems and methods involving the seal member are also disclosed.

Inventors:
DEVINE ERIC I (US)
MCKINNEY BRYAN E (US)
THAKARE SHUBHAM B (US)
SPILLANE GREGORY J (US)
Application Number:
PCT/US2023/011725
Publication Date:
August 03, 2023
Filing Date:
January 27, 2023
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
GIBRALTAR IND (US)
International Classes:
G02B6/50; F16L1/11; H02G9/02
Foreign References:
US20180196216A12018-07-12
US20160272774A12016-09-22
US20160376767A12016-12-29
US20200227904A12020-07-16
Attorney, Agent or Firm:
BARAONA, Robert C. (US)
Download PDF:
Claims:
CLAIMS

What is claimed is:

1. A seal member for a micro trench, the seal member comprising: a top flange; a central body extending orthogonally down from a middle portion on an underside of the top flange; a plurality of protrusions extending radially away from the central body; and an engagement feature positioned at a lower terminal end of the central body.

2. The seal member of claim 1 wherein the engagement feature has a triangular or V-shaped cross sectional profile.

3. The seal member of claim 1 wherein the top flange includes a central hinging groove formed on a top facing.

4. The seal member of claim 1 wherein at least one of the plurality of protrusions each includes a hinging groove.

5. The seal member of claim 1 wherein the plurality of protrusions extend radially away from the central body at a shorter radial distance than the top flange.

6. The seal member of claim 1 wherein the plurality of protrusions include one or more pairs positioned at an identical axial height on opposite facings of the central body.

7. The seal member of claim 6 wherein the pairs of protrusions each have a different radial extension, with a shortest radially extending pair positioned immediately next to the engagement feature.

8. The seal member of claim 6 wherein the pairs of protrusions have progressively shorter radial extensions so that a longest radially extending pair is positioned immediately next to the top flange and the shortest radially extending pair is positioned immediately next to the engagement feature.

9. The seal member of claim 1 wherein the plurality of protrusions extend perpendicularly away from the central body.

10. A system for sealing a micro trench, the system comprising the seal member of claim 1 and at least one selected from: i) an adhesive applied to a portion of the seal member, and ii) a curing foam used as a reinstating material.

11. The system of claim 10 wherein the foam is an elastomer configured to: i) flow around the seal member prior to curing and ii) adhere to the sealing member and any adjacent surface during and after curing.

12. The system of claim 10 wherein the foam includes urethane and/or silicone.

13. The system of claim 10 wherein the foam forms open or closed cell upon curing.

14. The system of claim 10 wherein the foam has a cream time of 1-30 seconds, a gel time of 2-60 seconds, and a tack free time 3-120 seconds.

15. The system of claim 10 wherein, when cured, the foam has a core density of 0.5 - 60 pounds per cubic foot and a compressive strength of 2-200 pounds per square inch.

16. The system of claim 10 wherein the system includes a mobile platform configured to transport and dispense the seal member and the adhesive and/or the foam.

17. The system of claim 16 wherein the mobile platform includes a guide mechanism, a discharge blade, and a compaction wheel.

18. The system of claim 17 wherein the mobile platform includes a plurality of storage tanks configured to mix a curing agent with the foam and/or the adhesive as it is dispensed.

19. A system for continuously sealing a micro trench, the system comprising: the seal member of claim 1, said seal member provided in sections that are each wound separately around a plurality of spools; a cutting tool configured to position the central bodies of seal members from a trailing edge of a first spool and the central body of a leading edge of a second spool, the cutting tool including a blade configured to remove a portion of at least one of the trailing edge and the leading edge; and a fastening implement configured to couple the trailing and leading edges positioned in the cutting tool.

20. The system of claim 19 wherein the fastening implement delivers a staple through the leading and trailing edge of separate sections of seal member.

Description:
Inventor: Eric Devine Bryan McKinney Shubham Thakare Greg Spillane

TITLE

SEAL MEMBER, SYSTEM AND METHOD OF SEALING A MICRO TRENCH

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to United States provisional patent application serial number 63/304,013 filed on January 28, 2022, which is incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The present teachings relate to a system and method for sealing a micro trench in pavement and methods of installation thereof, that is able to protect and provide access to utilities therein.

BACKGROUND

[0003] Micro trenching, or slot-cut trenching, is the process of cutting a small groove or small channel in pavement. Micro trenching is a growing practice used to install utilities such as fiber optic cable networks or other broadband network lines in a variety of residential, commercial, and industrial settings. The groove for micro-trenches are usually one quarter to several inches wide (typically no more than 1.00 to 2.00 inches, subject to a tolerance of 0.1-0.2 inches either way) and up to 12 inches or even 24 deep (with a minimum depth typically dictated by the size of the utility being installed and/or other conditions at the site, but typically at least about 1, 2, or 3 inches). Micro trenching is a low-impact deployment methodology and can be utilized without damaging or disrupting existing infrastructure, especially in view of the fact that existing trenching machinery creates a trench that is at least 5-6 inches wide (with an even larger footprint during the trenching operation itself).

[0004] Alternative excavation techniques often rely on a larger trench profile and/or substantial removal of pavement, which takes more time and involves greater expense. Specifically, equipment and labor for excavation and reinstatement are greater, and the larger footprint requires significant amounts of time and extensive roadway /lane closures. In comparison, micro trenching is faster, lower cost, and generally more efficient because it requires fewer resources. Further, since micro trenching requires less space and is generally less intrusive, installation by micro trenching usually results in less closures/changes to traffic patterns. And when properly reinstated and backfilled, micro trenches are not visually obtrusive, to the point of going unnoticed by casual observers.

[0005] Conventional devices and methods for executing a microtrench can be found in numerous patents, including United States Patent Publications 20180106015A1; 20180292027A1; and 20200149659A1. These publications all contemplate a continuous system in which a truck or trailer creates the micro trench and then fills it with a concrete-based material that can be selected to color-match the roadway. The fill material requires a set time of about 2 hours, with 30 to 40 minutes being preferred. Various cements and accelerators are recommended as the means to adjust the set time. Notably, even when relying on the most preferred conditions, the set times for these methods exceed the speed at which a micro-trench is dug, meaning that the reinstatement process is rate-limiting and dictates the pace at which operations can proceed.

[0006] Other conventional reinstatement methods involve the use of a flowable fill, such as that disclosed in EP1569021A1 and US20160201291A1. As an example, flowable fill may include hot applied rubberized sealants, cold asphalt material, or cementitious grouts (e.g., cement- based grout, bituminous sealer, etc.) placed directly on top of the buried utility (e.g., fiber optic cables, etc.). Especially after these fill materials set/cure, they do not allow convenient access to the underlying utility, thereby making subsequent service (e.g., for modifications, repair, or replacement) more difficult and expensive. A common means of overcoming these challenges is to simply create a new trench, usually in or adjacent to the existing trench and install separate/new utilities (and possibly remove the older line), all of which requires additional materials and labor costs. Because of the precision required to avoid damaging adjacent pavement and/or utilities, servicing flowable filled trenches and micro trenches tends to be time-consuming and increases the risk for other complications.

[0007] Conventional methods of reinstatement tend to have a relatively short life span in comparison to the pavement in which they are used. For example, pavement comprising hot mix asphalt (HMA) has minimal strength in the horizontal plane, especially at surface temperatures above 35°C. As a result of the differences in strength of adjacent materials at elevated (or reduced) temperatures, expansion and contraction is further exacerbated, with the resulting weakness and variability leading to gaps, cracks, potholes, and other defects in the riding or walking surface. Current flowable fill materials themselves can also be too flexible or have poor bond strength, allowing the trench walls to break apart or the fill material to debond and become dislodged. Bond failure, cracks, and potholes all lead to water ingress in or around the trench during freeze and thaw cycles, causing more damage and accelerating the degradation of the roadway/surface.

[0008] Since the need to connect an end user site and a given utility line often recurs over a period of time, secondary, perpendicular trenches intersect and overlap with the primary/longitudinal (following the direction of the road or walkway) trench. These crossover points lead create junctions along multiple and intersecting planes (i.e., at least twice as many in comparison to a single trench) that are all susceptible to the temperature cycling issues noted above. Thus, branching trenches have even greater chances for damage, pavement failure, and an overall reduction in lifecycle for the seal, the trench, and the roadway itself. The use of flowable fill or other non-matching or comparatively incompatible materials, both at the intersection points and/or between the secondary trench and the original surface/roadway itself, further compounds the problems.

[0009] FIG. 1A depicts a preformed sealant A that may be used in sealing expansion joints in concrete. The preformed sealant A, however, has been shown ineffective in micro-trenching and other applications outside of concrete, including asphalt. Moreover, such preformed sealants A have been shown to cause distress and distortion in the asphalt. In fact, the preformed sealants A not only cannot provide a proper seal in asphalt, but further, the preformed sealant A has been shown to cause “shoving” when used in asphalt, see FIG. IB. Shoving is the formation of ripples across asphalt, causing distortion and disruption of the surface. Such ineffective and improper sealing, as by the preformed sealant A, is also likely to cause other types of distress, including rutting, depressions, cracking, upheaval, disintegration, and other failures or disruptions in the asphalt trench and surface. This is believed to be caused, in part, by the compressive strength of the preformed sealant A and the flexible nature of the asphalt. As compared to concrete, the horizontal shear strength of asphalt is significantly lower than that of concrete.

[0010] FIG. 1C shows a compression deflection curve for the preformed sealant A having a 13/16” width. In concrete, the preformed sealant A of this size would be used in expansion joints with an opening range of about 0.375” to 0.688,” which may generally correspond to the operating range of a micro trench cut at about !4” which is about 0.375” to 0.625.” While the preformed sealant A of this size may have expected to provide an adequate seal such micro trench opening, quantitative results confirm that the preformed sealant A is not effective for use in a material having different compressive qualities and horizontal strength of concrete, such as asphalt. As shown in FIG. 1C, at the minimum joint opening the compressive force (stored energy) of the preformed sealant A is at a maximum. For example, a joint opening of about 0.375” corresponds to about 0.437” compressive extension, or about 20 psi compressive stress. Further, at hotter temperatures, asphalt may be softer and more flexible.

[0011] Given the foregoing, new and improved sealing systems, removable and/or resealable members, reinstatement materials, and methods for creating and reinstating micro trenches are needed. In particular, these should ideally provide a fast and reliable seal, allow for subsequent access to the utilities contained in the micro trench, enable minimal disruptions to the surrounding roadway/surface, and possess superior ability (in comparison to conventional methods) to withstand environmental and expected wear/use conditions for that roadway/surface. Materials and methods that can be installed at a rate that matches or exceeds the speed of the existing pavement cutting operations would also be welcomed, as would a system that is capable of coupling together extended spools of seal members without interrupting the trenching operation.

DESCRIPTION OF THE DRAWINGS

[0012] The present teachings may be better understood by reference to the following detailed description taken in connection with the following illustrations, wherein:

[0013] FIGs. 1A and IB are side and top views of a preformed sealant A of the prior art typically used in sealing expansion joints in concrete FIG. 1C shows a compression deflection curve for the preformed sealant A;

[0014] FIG. 2 is a side view of an embodiment of a sealant system or apparatus in accordance with various disclosed aspects;

[0015] FIG. 3 is a side view of the embodiment of of FIG.2 positioned in a micro trench in accordance with various disclosed aspects;

[0016] FIG. 4 is a top view of an embodiment of a sealant system or apparatus positioned in a micro trench in accordance with various disclosed aspects; [0017] FIG. 5 illustrates method of installing an embodiment of a sealant system or apparatus positioned in a micro trench in accordance with various disclosed aspects;

[0018] FIG. 6 is a side view of another embodiment of a sealant system or apparatus in accordance with various disclosed aspects;

[0019] FIG. 7 is a side view of another embodiment of a sealant system or apparatus positioned in a micro trench in accordance with various disclosed aspects;

[0020] FIG. 8 is a compression deflection curve of a sealant system or apparatus in accordance with various disclosed aspects;

[0021] FIG. 9 schematic view illustrating a testing core and the test fixture configured to determine compatibility of a sealant system or apparatus in a material in accordance with various disclosed aspects;

[0022] FIG. 10 is a photograph of a trial installation of a sealant system or apparatus in a trench at a testing site in accordance with various disclosed aspects;

[0023] FIG. 11 are force/deflection curves for core tests and core testing samples at 3.22 psi in accordance with various disclosed aspects;

[0024] FIG. 12 are force/deflection curves for core tests and core testing samples at 9.4 psi in accordance with various disclosed aspects;

[0025] FIG. 13 are force/deflection curves for core tests and core testing samples at 20 psi in accordance with various disclosed aspects;

[0026] FIGs. 14A and 14B are photographs of a trial installation of a sealant system or apparatus in a trench at a testing site over time in accordance with various disclosed aspects;

[0027] FIG. 15 is a side view of an alternative embodiment of a sealant system or apparatus in accordance with various disclosed aspects;

[0028] FIG. 16 is a side view of the embodiment of FIG. 15 positioned in a micro trench in accordance with various disclosed aspects; [0029] FIGS. 17A and 17B show, respectively speaking, a three dimensional, perspective view and a botom view of an installation machine in accordance with various disclosed aspects; and [0030] FIG. 18 is a schematic side view of a platform useful for simultaneously laying fiber, cable, or other spooled media within a trench, while also providing foam backfill and a sealant system in accordance with various disclosed aspects.

[0031] FIG. 19 is a side view illustration of a splice between seal members made according to certain aspects of the invention.

[0032] FIGs. 20A and 20B are schematic illustrations of cutting tools appropriate for use with the splicing operations according to certain aspects of the invention.

DETAILED DESCRIPTION

[0033] Reference will now be made in detail to embodiments of the present teachings, examples of which are illustrated in the accompanying drawings. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the scope of the present teachings. Moreover, features of the embodiments may be combined, switched, or altered without departing from the scope of the present teachings, e.g., features of each disclosed embodiment may be combined, switched, or replaced with features of the other disclosed embodiments. As such, the following description is presented by way of illustration and does not limit the various alternatives and modifications that may be made to the illustrated embodiments and still be within the spirit and scope of the present teachings.

[0034] As used herein, the words “example” and “exemplary” mean an instance, or illustration. The words “example” or “exemplary” do not indicate a key or preferred aspect or embodiment. The word “or” is intended to be inclusive rather an exclusive, unless context suggests otherwise. As an example, the phrase “A employs B or C,” includes any inclusive permutation (e.g., A employs B; A employs C; or A employs both B and C). As another matter, the articles

“a” and “an” are generally intended to mean “one or more” unless context suggests otherwise. [0035] A spoolable, branched, and T-shaped seal member and a specially formulated open or closed cell, curable foam can be implemented as part of a micro trenching system. These components can be provided on a single, unitary trailer or vehicle, or they can be retrofitted with/into existing trenching equipment and operations. The seal member itself may be removable and serviceable, while the installation of foam and/or the seal member results in a sealed micro trench that is water tight, comparatively resilient, and resistant to damage caused by heavy usage and/or environmental factors.

[0036] The seal member has suitable compressive strength to support the trench walls without damaging adjacent pavement (or other roadway/surface materials). The construction of the seal member will accommodate expansion and contraction caused by changes in temperature (i.e. , the freeze/thaw cycle) and/or traffic load while remaining firmly locked into any reinstating material (when used), and it can be provided as a spooled material, which is ideally suited for existing installation machines and further enables the seal member to be dragged, dabbed, or otherwise exposed to an adhesive as it is laid down into the trench and/or in contact with the utility line(s).

[0037] The foam is provided as a two part liquid, making it ideal for storage in and in situ dispensing from tanks. After the parts are mixed, the resultant material can flow and expand around any objects positioned within the trench (e.g., the utility line(s), the seal member, etc.) and then cure into a closed or open cell solid material.

[0038] The sealing system and method may accommodate multiple parallel and/or intersecting/perpendicular micro trenches within a given road, street or other pathway/surface, irrespective of whether provided through intersections of cross streets or at various junctions from a mainline in a street to an end user/property adjacent to that street. The system is capable of withstanding vehicle and/or pedestrian travel, varying environmental conditions, and other wear and tear. Additionally, the disclosed micro trench seal may allow for removal, targeted replacement of the utility, and reuse, all while maintaining integrity of the original micro trench. The system is also configured to operate continuously by relying upon specialized tooling that enables the splicing of seal members from separate spools without pausing operations (i.e., without stopping cutting, reinstating, or sealing of the micro trench). As one non-limiting example, the system includes a cutting tool with a blade that partially removes the top flange and/or central body from the trailing edge of a seal member wound onto a first spool and/or the leading edge of a seal member wound onto a second spool. The cutting tool integrates or the system includes a separate holder that positions these leading and trailing edges, both for purposes of cutting and to allow a fastening implement to couple the leading and trailing edges together. In one aspect, that fastening implement may deliver one or more metal (copper, steel, etc.) or sufficiently hardened plastic staple, joint, or clip so as to hold the two edges together, preferably through overlapping portions of the main body and/or the top flange.

[0039] Turning to FIGs. 2-3 and 15-16, seal member 1 has a core T-shape, with the stem or main body 4 defining a central structural axis. A flat head or top flange 2 is positioned at the top end 12 of the body 4, while a plurality of appendages or protrusions 3 extend radially (perpendicular to or an angle) from central section 16 of the body 4. At the lower end 14, an engagement feature 7 allows reinstating material, such as a foam, to flow and cure around the feature to keep the member 1 locked in place within the trench. The feature may take the form of a solid triangular shape (Fig. 2), an inverted V-shape (Fig. 15), or other similar structures, provided that the radial extension of the feature 7 is smaller than the corresponding radial extension of the set of shortest protrusion 3 (usually, the bottom-most set of protrusions 6).

[0040] As used herein, “axial” refers to the vertical direction of the member 1 as shown in the figures, while “radial” extensions will trace a generally horizontal direction although, unless otherwise stated herein, radial protrusions, extensions, and the like may be provided at a perpendicular or angled orientation relative to the central axis coinciding with the axial length of the main body 4. Also, references to “trench” and “micro trench” may be used synonymously, depending upon the specific context of their use.

[0041] It will also be understood that the member 1 is illustrated in cross section, but it will be manufactured (e.g., by way of extrusion) continuous web so that it can be reeled around a spool or otherwise gathered for subsequent dispensing and use. Thus, the cross sections shown in Figs. 2, 15, and elsewhere are part of a body that otherwise can run on for extended lengths (as would be expected and needed for the seal member to be unspooled and positioned into a micro trench).

[0042] The seal 1 may be inserted into a micro trench 200 in any suitable manner, including by inserting the second end 14 first with the protrusion(s) 3 extending into contact with walls of the micro trench as described in more detail below. More specifically, the micro trench may include sidewalls 204 and an opening 206. The seal 1 may engage a surface of the pavement 202 generally adjacent to the micro trench. The seal 1 is ideally formed from an appropriate polymeric resin selected for the particular temperature and pressure conditions encountered in trenching operations. In one embodiment, the material can be a thermoset elastomer material. In another embodiment, the resin material can be a thermoplastic material. In other embodiments, the material may be a combination of the foregoing. The material can be resistant to environmental conditions such as water, ozone, oxidation, and UV.

[0043] The shape of the seal 1 may be formed using an extrusion process and may be cured to achieve its final desired properties. The seal 1 may be machine molded in a single continuous step so as to facilitate spooling. The entire seal 1 may be formed from the same material or different portions of the seal 1 may be formed from different materials that are subsequently adhered, welded, or otherwise bonded together. For example, the protrusions 3 or the ends of the protrusions may be formed from a more flexible rubber material or the top flange 2 may be formed from harder materials able to withstand wear from environmental conditions and use. [0044] Examples of suitable materials include, but are not limited to, rubber-like polymers including, polyisoprene, butadiene rubbers, styrene-butadiene copolymers, such as Buna S and SBR, cis -polybutadiene, cis -polyisoprene, nitrile elastomers or NBR rubbers (also known as acrylonitrile and butadiene copolymers) such as Buna N, butyl rubbers including copolymers of isobutylene and isoprene, ethylene-propylene monomer (EDM), ethylene-propylene-diene monomer (EPDM), neoprene (polychloroprene), polysulfide rubbers (thiokols), ethylenepropylene rubbers (RPDM), urethane elastomers, and silicone rubbers such as dimethysilanediol polymers and polydimethyl siloxane, fluoroelastomer, polyacrylate elastomer, polyethylene (chlorinated, chlorosulfonated), styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), EPDM-polypropylene blend, and combinations of two or more thereof.

[0045] Other suitable materials may include, but are not limited to, plastics such as polycarbonate; acrylonitrile butadiene styrene (ABS); polycarbonate/acrylonitrile butadiene styrene alloys (PC-ABS); polybutylene terephthalate (PBT); polyethylene therephthalate (PET); polyphenylene oxide (PPO); polyphenylene sulfide (PPS); polyphenylene ether; modified polyphenylene ether containing polystyrene; liquid crystal polymers; polystyrene; styreneacrylonitrile copolymer; rubber-reinforced polystyrene; poly ether ketone (PEEK); acrylic resins such as polymers and copolymers of alkyl esters of acrylic and methacrylic acid styrenemethyl methacrylate copolymer; styrene-methyl methacrylate-butadiene copolymer; polymethyl methacrylate; methyl methacrylate-styrene copolymer; polyvinyl acetate; polysulfone; polyether sulfone; polyether imide; polyarylate; polyamideimide; polyvinyl chloride; vinyl chloride-ethylene copolymer; vinyl chloride-vinyl acetate copolymer; polyimides, polyamides; polyolefins such as polyethylene; ultra high molecular weight polyethylene; high density polyethylene; linear low density polyethylene; polyethylene napthalate; polyethylene terephthalate; polypropylene; chlorinated polyethylene; ethylene acrylic acid copolymers; polyamides, for example, nylon 6, nylon 6,6, and the like; phenylene oxide resins; phenylene sulfide resins; polyoxymethylenes; polyesters; polyvinyl chloride; vinylidene chloride/vinyl chloride resins; and vinyl aromatic resins such as polystyrene; poly(vinylnaphthalene); poly(vinyltoluene); polyimides; polyaryletheretherketone; polyphthalamide; polyetheretherketones; polyaryletherketone, and combinations of two or more thereof.

[0046] The stem 4 may include a first end 12, a second end 14, and a middle section 16 disposed between the first and second ends 12, 14. In an embodiment, the stem 4 may be inserted into the micro trench 200 such that most or all of the body 16 is generally below the surface of the pavement 210, see FIGs. 3 and 16. The length of the stem 4 may be customized at the installation site once the dimensions of the micro trench 200 are confirmed, for example, by cutting off any access material or length. In such cases, the sets of protrustions provided closest to the bottom end 14 will have a shorter radial extension in comparison to the sets above it. In this manner, the cut can be made immediately adjacent to the bottom edge of a protrusion, thereby converting the lowermost protrusion into the engagement feature 7.

[0047] The stem 4 may be thick enough, such as one quarter to one eighth of the width of the top web, to maintain the center of the joint generally without twisting or buckling, creating a self-centering effect. The first end 12 of the stem 4 may include the top flange 2 or the top flange 2 may be positioned thereon.

[0048] The top flange 2 may be removable from the stem 4. In an embodiment, the top flange 2 may be removed, and a different sealing mechanism or material used in conjunction with the stem 4. The top flange 2 may also be removed from the stem 4 and replaced by another top flange 2, for example, if the top flange 2 becomes damaged during use. The top flange 2 may also be removed and a coating of bituminous crack filler can be added to extend the life of the seal. The top flange 2 may also be configured to become detached from the stem 4 upon certain threshold pressure or conditions so that the stem remains in the micro trench 200 in the event the top flange 2 is pulled, detached, dislocated, or otherwise removed unintentionally or intentionally. In a non-limiting embodiment, the top flange 2 may be caught by a snow plow, street cleaner, truck, car, or the like. It may be desirable to have the top flange 2 selectively detached or be stripped off from the stem 4 under these conditions so that any damage is concentrated on the top flange 2 that can be replaced, rather than the stem 4 or the structure of the micro trench 200 and to prevent the entire seal 1 from inadvertently being removed from the micro trench.

[0049] In an embodiment, the top flange 2 may include an elongated portion 22 that extends generally perpendicular (e.g., within 5 degrees of perpendicular) to the stem 4. The top flange 2 may be planar, flat, domed, rounded, squared, or be formed as any other shape as may be desirable. In an embodiment, the elongated portion 22 may include a sufficient length to accommodate a large portion or length of the micro trench 200, for example several feet, see FIG. 4 for example. In this embodiment, several stems 4 may attach to the top flange 2 across its length to secure the seal 1 into the micro trench 200. The elongated portion 22 of the top flange 2 may include a first face 24 and a second face 26, wherein the second face 26 may attach to or face the stem 4. As described above, in an embodiment, the top flange 2 may be removable from the stem 4. When installed in a micro trench 200 the first face 24 may face outwardly from the micro trench 200, see FIGs. 3-4, as well as FIG. 16. In an embodiment, the top flange 2 may be of sufficient width to span the entire trench and lay generally flat on the pavement surface, see FIGs. 3 and 16, e.g., it may he such that only a centimeter or less is above or below the adjacent surface. The top flange 2 may be larger than the micro trench 200 such that the top flange is not fully inserted into the micro trench 200.

[0050] In an embodiment, the second face 26 of the top flange may include a notch 28 to fit on the edge of the micro trench 200 with the notch contacting a sidewall 204 of the micro trench 200 and the surface of the pavement 202. The notch 28 may help to form a seal and may provide additional securement of the seal 1 within the micro trench 200. The notch 28 may be sized for and be equal to the size of the micro trench opening. The notch 28 may be formed in the seal 1 at manufacture, or the notch 28 may be added at the installation site once the dimensions of the micro trench 200 are confirmed.

[0051] In another embodiment, the top flange 2 may generally be the same width as the micro trench 200, such that the top flange 2 may be inserted into the micro trench 200. The top flange 2 may create a seal against the side walls 204 of the micro trench 200 (similar to the protrusions described below) and another seal material or mechanism may be placed on top, such as a fill material. The top flange 2 may be any suitable shape including rectangular, circular, square, etc. The top flange 2 may be any suitable shape so as to keep debris or water out of the micro trench opening 206.

[0052] The seal 1 may include at least one protrusion 3 extending from the body 16 or second end 14 of the stem 4. The protrusion 3 may be formed as arms or wings that extend from opposite sides of the stem 4 in pairs to engage each of the corresponding side walls 204 of the micro trench 200. The protrusion 3 is a continuous flange that may extend perpendicularly or generally perpendicularly (i.e., radially away) from the stem 4, e.g., at angles within about 15 degrees of perpendicular. In an embodiment, the protrusions 3 extend from the stem 4 at an angle toward the top flange 2, see FIG. 2. Although FIG. 2 illustrates an embodiment having three sets of arms, or wings, it is noted that any number of protrusions may be used, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, etc. In an embodiment, the protrusion is of a sufficient length to maintain may contact the sidewall of the sidewalls 204 of the micro trench 200 with normal variation in temperature and expansion or contraction of the pavement. The length of the protrusions 3 may be customized at the installation site once the dimensions of the micro trench 200 are confirmed, for example, by cutting off any access material or length. As described herein, asphalt or HMA may be particularly susceptible to variations in temperature and can result in changes in width of the micro trench 200.

[0053] The protrusions 3 may extend at approximately the same radial distance on either side of the stem, so as to allow easily centering the seal 1 within a microtrench 200. Additionally, as shown in FIG. 3, the protrusions 3 may have the same comparative radial distance, although it is preferably smaller than the distance spanned by the top flange 2. Alternatively, the protrusions 3 may be shorter in length in comparison to top flange 2 (as shown in FIG. 15) and/or in comparison to one another, so that the distal edges and radial distance of each flange gets progressively smaller as the protrusions progress from the first end 12 to the second end 14, as this arrangement allows for the seal 1 to interlock with a foam backfill material, as described below. The protrusions 3 may be formed as pairs so that each pair is positioned at a different axial distance (relative to the top flange), or the protrusions may be axially offset from one another so that the protrusions extend away from the central body in an alternating fashion as they move down the central body.

[0054] Notably, the protrusions 3 and the top flange 2 are of sufficient strength so that when positioned as shown in FIGs. 3 and 16, any foam backfill material will be impeded from flowing around the distal edges of the protrusions 3. In this manner, the seal insures that foam cannot and will not expand upward out of the trench or to otherwise be visible when the installation is complete.

[0055] One or more sets of the protrusions 3 may include one or more hinge points 5 that allow the seal 1 to fold against the pavement or side walls 204 of the micro trench 200, increasing the sealing area, see FIGs. 3 and 16. Owing to the continuous web nature of the sealing member 1, hinge points 5 are formed as continuous grooves. The top flange 2 may also include a hinge point 5.

[0056] In an embodiment, bottom-most set of protrusions 6 inserted into the micro trench may not include a hinge point 5 while the remaining, higher sets of protrusions 3 may include a hinge point 5, see FIG. 3. The bottom-most set of protrusions 6 not including the hinge point 5 may permit the seal to engage the micro-trench with more force than the other protrusions 6 with the hinge point 5 - this may prevent the seal 1 from being pulled out of the micro-trench.

Each protrusion 3 may operate independent of the others, creating a seal at each protrusion location that is custom to the shape and contours of the micro trench 200. In an embodiment, providing the additional sealing protrusions and hinges not only may better secure the seal 1 within the micro trench and create a seal at multiple locations, but can also provide continuous service even if the top flange 2 or a protrusion 2 is damaged or the pavement is compromised at one location. In these embodiments, when a force is applied to the top flange 2, it may shear before the entire seal 1 is removed from the micro trench.

[0057] In an embodiment, the location of the hinge 5 may be designed specifically for the opening dimensions of the micro trench 200 to maximize sealing yet control the outward force that would disturb asphalt. The hinge 5 may also ensure that less pressure is applied onto the side walls 204 of the micro trench where the asphalt in the micro trench may be the weakest. For example, the asphalt may be weaker toward the top of the opening of the micro trench. As a result, the protrusions 3 inserted into this area of the micro trench may include a hinge 5 to reduce the force and prevent too much force to be applied from the protrusions 3 to the side walls 204. On the other hand, the side walls 204 of the micro trench may be stronger further down into the micro trench. As a result, the protrusions 6 inserted into this area of the micro trench may not include a hinge 5 because damage due to the force of the protrusions may not be as much of a concern and instead, it may be desirable to have a greater force and seal in this area of the micro trench to further secure the seal 1 into the micro trench. The hinge 5 may be formed in the seal 1 at manufacture, or the hinge 5 may be added at the installation site once the dimensions of the micro trench 200 are confirmed.

[0058] Notably, the second end 14 will have a radial distance that does not exceed the reach of the top flange 2 and, more preferably smaller than the reach of the protrusion 3 immediate above and adjacent to it. However, in contrast to the protrusions 3, second end 14 may slope at an angle (in comparison to the generally perpendicular protrusions 3). In this manner, the end 14 may have a cross-sectional shape that is triangular (as seen in FIG. 3) or, by way of two angled legs, V-shaped (as seen in FIG. 15). [0059] Although this embodiment describes protrusions 3 including a hinge point 5, it is noted that a micro trench seal 100 may also be provided without a hinge point, see FIGs. 6-7 (and this arrangement may be implemented on the seal 1 shown in FIG. 15). As disclosed herein, the seal 100 may include a top flange 102, at least one protrusion 103, and a stem 104. The incorporation of a hinge point may depend on the nature and integrity of the material forming and surrounding the micro trench, weather or environmental conditions, anticipated use of the road or pathway, material of the micro trench seal, and the like. In an example, the shape of the protrusions 103 may be altered to create variable force on the micro trench walls. The protrusions 103 may be made thinner or thicker, having a different circumference, of a material having a different flexibility, and the like.

[0060] The micro trench seal 100 and the seal 1 are exemplary embodiments. The present disclosure contemplates seals of different configurations. For example, the features disclosed above regarding seal 1 may be combined with micro trench seal 100 and the features disclosed above regarding micro trench seal 100 may be combined with seal 1. Moreover, the seal 1 and micro trench seal 100 may be of different configurations without departing from the present teachings. In one example, the seal 1 and/or micro trench seal 100 may be formed from the material described above, be serviceable and be of varying configurations that operatively fit within a micro trench as described above.

[0061] Thus, after the trench is cut and the utility is placed at the bottom of the trench a foaming material is sprayed or pumped into the trench. Before the foam fully reacts and cures, seal 1 is inserted in the top of the trench to confine the foam material within the trench. The foam material is an elastomeric material that can be urethane or silicone, with either a closed cell or open cell (preferred for waterproofing the trench) form upon curing. The foam material bonds to the trench walls and seal closing off the trench to water or incompressible materials to prevent spalling. [0062] The interlocking arrangement of the seal 1 shown in FIGs. 15 and 16 improves the water tightness of the system and prevents the seal from being pulled from the trench.

[0063] Appropriate foam backfill materials are preferably elastomeric foams based on urethane and/or silicone polymer, provided as a single or plural component system. The foam should have a cream time in the range of 1-30 seconds, a gel time in the range of 2-60 seconds, and a tack free time in the range of 3-120 seconds. Once cured it has a core density of 0.5 - 60 pounds per cubic foot and a compressive strength of 2-200 psi. The foam could be hydrophobic to allow it to fully cure in hydrostatic conditions, allowing for installations in damp conditions. Typical geotechnical foam literature provided for Penefil 375. The foam should be capable of bonding to the pavement and the elastomeric sealing element. Also, the foam may be supplied in small hand mixed batches or bulk kits to allow pumping into the installation/trench.

[0064] Additionally or alternatively, as the seal member is disposed within the trench, it may be coated, dragged through, or otherwise come into contact with a curable adhesive. This adhesive would bond the seal member to the utility line(s) and/or the trench walls, so as to maintain the desired positioning of the seal member throughout the trenching and reinstating procedures. However, use of the adhesive — and of the foam itself — can be dictated by the conditions and needs of the installation. When used, the adhesive may be any common adhesively, preferably water based or a two-part system.

[0065] Pumping and injection systems should be electronically controlled to mix and place the appropriate volume of material in the trench based on the trench dimensions and the rate of travel to ensure a continuous process. The pump should include a spray head that applies the foam to the sidewalls of the trench to ensure full coverage of the trench walls. The head should be aligned with the trench such that the foam is applied so that the foam coats the trench walls and embeds itself in the seal. The pump should have the capability to heat the foam material to provide for a consistent cure rate and foam time. The pump should also include an air purge for when work stoppages occur. [0066] Turning to FIG. 5, shown is a method 300 of installing a seal 1. At step 3002, a micro trench is formed by excavating material such as pavement and dirt, to a desired width and depth as is necessary for the particular utility being installed. For example, the dimensions of a micro trench may range from 12 inches in depth, 0.5 inches in width, and 5,000 foot length - although these are merely exemplary any the micro trench may be of any appropriate dimension. At step 3004, a utility may be installed. The utility may include broadband network access such as fiber optic lines. At step 3006, the seal 1 may be inserted into the micro trench 200. The installation of the seal may occur concurrently with the installation of the utility. The installation of the seal 1 may be done by hand by pressing the seal 1 into the opening 206 of the micro trench 200 or by machine. In an embodiment, the structure of the seal 1 may enable installation of the seal 1 by hand where otherwise a machine would usually be needed. The seal 1 may provide improved on site installation capabilities and may minimize the need for additional machinery to facilitate installation of the seal 1. In this step 3006, coupling or splicing trailing and leading edges of separate sections of seal members is possible.

[0067] In an embodiment, an adhesive may be used to facilitate the installation of the seal 1 into the micro trench. The adhesive may be spray on, paint on, stick on, or the like. In an embodiment, a machine may be used to control the volume of an adhesive, such as a spray on adhesive, applied during installation. The seal 1 may be customized at the installation site by adjusting the length of the stem 4, the protrusions 3, the notch 28, and the hinges 5. For example, excess length of the stem 4 or protrusions 3 may be cut or material removed to form the notch 28 or hinges 5. In an embodiment, the seal 1 should be inserted to a depth that allows the top flange 2 to remain flush with the surface of the pavement 202. The seal 1 can be installed with or without adhesive. In an embodiment including adhesive, the adhesive should have a high enough viscosity to have a lubricating effect and a long enough open time to allow for adjustment of seal depth. If the micro trench 200 is cut excessively deep it may be desirable to partially fill the trench with dry fill material such as sand or spoils left over from when the trench was cut.

[0068] Because micro trenches are often deployed along hundreds or thousands of linear feet, another aspect of the invention relates to equipment that enables the continuous dispensing and positioning of the seal member. That is, the seal member is easily transported by winding it around a spool, but spools (and other similar storage means) can only hold a finite length of the seal member. When the micro trench length exceeds the length of seal member wound onto the spool, the system can be configured to include multiple spools and to splice the edges of seal members from separate spools, by way of a cutting tool and a fastener. In this manner, if 500 feet of seal member can be spooled onto a storage reel, a mobile platform outfitted with ten full reels positioned adjacent to one another will effectively enable installation of up to one mile of sealed micro trench. The ability to install greater length of trench without stopping is particularly beneficial to the extent that other aspects of the invention (e.g., the shape of the seal and/or the use of foam/adhesive) already increase the speed of micro trench operations.

[0069] In some aspects, the mobile platform might include one or more bars or a T-shaped hanging rods that allows spools to be loaded and removed from one or both ends of the bar/rod. Alternatively, the spools could each be associated with a movable stand or base. In either instance, a plurality of filled spools are readily accessible or in close proximity so as to minimize the amount of slack that must be created during the splicing operations described below.

[0070] The cutting tool can come in any number of arrangements. Critically, it will include a positioning member, such as a longitudinal channel and/or guide members, into which the leading and trailing edges of seal members from different spools are provided (with respect to the trailing edge, an operator will need to monitor progress and proactively couple these edges before they are placed into the trench, possibly with the further need to release the trailing edge from its spool). As implied by the name, the cutting tool also has a blade or implement to facilitate removing a portion of the seal member from one or both edges, ideally by way of cutting axially or radially into that seal member. This cut allows for positioning of the edges in order to fasten them with the fastening implement, while simultaneously retaining the apparent continuity of the top facing of the top flange (for cosmetic purposes). These positioning and cutting functions can be integrated within a single tool, or they can be provided as separate features of the system.

[0071] The fastening implement couples the trailing and leading edges together in a fast and cost efficient manner. It should be portable, easy to use, and avoid the need to cure or otherwise take time to effect a connection over a period time that might otherwise slow or disrupt installing of the sealing members. In these regards, the inventors have identified conventional industrial staples as an ideal solution.

[0072] Staples are attractive in part because of their ubiquitous nature. Further, they immediately couple members by having their opposing terminal edges of the staple penetrate the seal member, after which the staple edges are crimped inward so as to hole the staple securely in place. Simple U-shaped members made of copper, steel, other metals, sturdy plastics, or any other material that is sufficiently strong enough to pierce the material selected for the seal member and to withstand crimping. Other possibilities include clips, which rely on a biasing member to hold the edges together, and/or double-ended receiving joints where the edges can be slid into and/or secured to opposing sides of the joint member.

[0073] The fastening implement can be a stand alone feature, such as a hand held stapler so as to provide the operator with greater freedom to manipulate and position the necessary components. Alternatively, the stapling mechanism could be integrated within a portion of the cutting tool so as to guarantee consistent and proper positioning of the trailing and leading edges throughout the splicing operation (i.e., positioning the separate edges, cutting/removing a portion of one of the edges, and coupling the edges via the fastener/fastening implement). [0074] The cutting tool can be any number of implements, from a hand held device up to an integrated workstation on a mobile platform. In operation, it includes a positioning and/or securing mechanism, such as a slot, spring-loaded grippers, or the like. A blade or cutting surface (die) can move across one edge of the securing mechanism so as to create a clean and angled or shaped cut through a portion of the seal member. The use of an angled cut (e.g., as seen along the leading edge 31b in Fig. 19) insures that the edges do not have to be perfectly aligned prior to fastening. A second positioning and/or securing mechanism can be provided and spaced apart from the first so as to allow both the lead and trailing edges to be held independently.

[0075] The tool can also include flanges (e.g., horizontal members on one or both transverse edges of the securing mechanism). These flanges may allow for holding and positioning the tool, and/or they may serve as means to attach or fasten the tool in place on a mobile platform, preferably adjacent to the spools carrying the seal members. Alternatively, the tool could be two or four blocks spaced apart to define a channel, with a guillotine-style cutting implement also provided.

[0076] At step 3008, the seal 1 or the top flange 2 may be removed as necessary. The components may be removed to allow access to the utility in order to fix or replace the utility, or the components may be removed and replaced if due to damage or wear and tear, as for example, by a snow plow. The seal 1 is able to allow continued access to the utility through its duration of use while both maintaining its integrity within the micro trench and adapting to the changing conditions of the micro trench due to various environmental conditions such as varying temperature. Notably, step 3008 is optional; however, when it is employed, the seal that was removed may be reused or repurposed to reseal the micro trench according to at least some subset of the previously mentioned steps 3002, 3004, 3006.

[0077] FIG. 8 shows a compression deflection curve for the seal 1 (this is a result from a test to measure the force to compress an objection, such as through ASTM D575). In an embodiment, at the minimum joint opening of about 0.375”, the maximum force is only 3.22 psi. Compared to the compression deflection curve of preformed sealant A shown in FIG. 1C and indicating a 20 psi compressive stress, the force and stress applied in the trench by seal 1 is much less and therefore is less damaging to the trench. In an embodiment, seal 1 is a low force seal that may provide an effective seal in materials that have different compressive qualities and horizontal strength than that of concrete, such as asphalt. In an embodiment, seal 1 may provide an effective seal in such materials, may not disrupt the structure of the materials in the walls of the trench or surrounding surface (e.g. prevent shoving, rutting, depressions, cracking, upheaval, disintegration, and other failures or distress), and may allow access to the underlying utilities after installation. The seal 1 may also provide a cost effective and low profile solution, minimizing the time, expense, resources, and obstruction to the road or walkway during and after installation.

EXPERIMENTAL DATA

[0078] A Marshall test may be used as a quality control tool for evaluating asphalt mixtures. Marshall stability and flow may also be used to relatively evaluate different mixes and the effects of conditioning. In this method, the resistance to plastic deformation of a compacted cylindrical specimen of a bituminous mixture is measured when the specimen is loaded at a deformation rate of 50 mm per minute. The current method, however, is only suitable for testing asphalt mixes rather than a sample of asphalt or asphalt that has already been in place. The results disclosed herein indicate that a modified Marshall test could be used to determine if asphalt or pavement that is already in place may be suitable for use with a particular sealant. The modified Marshall test may comprise making cut made through the core to represent the trench sidewall as noted in more detail below.

[0079] Experimental data was acquired using a modified Marshall test applied to various samples of asphalt to determine compatibility with the seal 1. Testing was performed using testing cores 200, an example of which is shown in FIG. 9. The testing cores 200 were taken and formed from asphalt testing sites at various locations as described herein. A testing core 200 having a diameter of 6 inches sample was used as it is large enough to measure force distribution, but not too large to make testing cumbersome.

[0080] Since the asphalt or pavement would be used for a trenching application, a fresh cut through the testing core 200 was carried out to determine and evaluate properties. A cut in the testing core 200 was made at the diameter of the testing core 200 to ensure adequate material was left for testing and to eliminate any comer effects. The testing core 200 was constrained in an epoxy form 210 to provide proper support of the testing core 200 when force 220 is applied. A force 220 of 3.22 psi was used based on the corresponding deflection curve, see FIG. 8. The epoxy form 210 also represented an infinite plane of asphalt. A bar 230 was used to transfer the load 220. The bar 230 had 1 inch by 1 inch dimensions with an area of 4.988 in 2 . This area represented the height of the seal 1 that may be in contact with the trench or asphalt surface when installed. The testing cores 200 were cut to a 2 inch depth. The bar 230 was aligned with the top edge 205 of the testing core 200 to simulate sealing the top of the trench. Testing was performed on an Instron 3366 test frame with an environmental chamber installed for testing at elevated temperatures. For elevated temperature testing the samples were conditioned in a Tenny environmental chamber for 24 hours at 140°F and 80% RH.

[0081] Test sites were selected to ensure a relatively good sampling of materials. Test sites varied from extreme heat and sun to cold and wet climates, and pavement condition varied from new to old and worn. At six test sites, two trenches were cut having a 25 foot length and 1-2 testing core 200 samples taken. At one test site, a single trench having a 45 foot length was cut and no testing cores 200 were able to be taken due to the location being a city street. Testing cores 200 were taken with a diamond hole saw. Trenching was performed using a Ditch Witch MT9 trenching saw mounted on an SKI 050 Mini Skid Steer. A half inch saw blade was used.

Trenches were cut 3-5 feet apart with a target trench dimension of 0.625 inches and 4-5 inches in depth. The trenches were then backfilled with sand to create a seal reservoir that was 1.5 inches deep. Seal 1 was installed at each location. FIG. 10 shows an exemplary installation in a trench in Sacramento, CA. These locations, the age and condition of the pavement, the sample date, and notes are shown below in Table 1. Trenches were monitored for 6 weeks for shoving, cracking, or other distress in the asphalt.

TABLE 1:

[0082] Testing of each testing core 200 began at room temperature. The testing cores 200 were then placed in an environmental chamber for 24 hours at 140°F and 80%RH for conditioning. Tests were repeated at 140°F and the results compared. FIG. 11 shows the force and the deflection curves for a set of testing core 200 samples in Cincinnati, OH. Table 2 shows the deflections of pavements at the different temperatures and a comparison of the results thereof. The increasing slope of the curve in FIG. 11 indicates an increased resistance to movement, i.e. minimal deflection. A comparison of the deflections in Table 2 further confirms that there is no evidence of shoving at the 3.2 psi loading. Differences in deflection ranged from 0-0.003 inches. TABLE 2:

[0083] The test method and results were validated by performing a trial in which shoving was detected. Samples were rerun in a hot state to a force of 9.4 psi. This force exceeds the force observed in seal 1. As shown in the Cincinnati, OH sample in FIG. 12, shoving was detected in this higher force experiment by the rapid change in the slope of the curve. The slope of the curve also started to increase again after 0.010 inches of deflection. Testing was repeated on the second testing core to 20 psi in the hot state (since the original preformed sealant A that caused shoving during field trials had a compressive force of 20 psi). The resulting deflection curve is shown in FIG. 13. The curve of FIG. 13 shows there are several changes in slope during the cycle. These changes in slope may be caused by compaction of the material as large aggregates move past each other or break away, causing the slope to change. Overall, this data confirms that seal 1, exhibiting a low compressive force or stress, does not result in shoving of asphalt, whereas preformed sealant A or other sealants exhibiting a higher compressive force or stress, do result in shoving or distress to the asphalt (shown by a jump in deflection over a short stress increase). [0084] The results of the trial installations confirmed this core testing. None of the sites showed any sign of shoving when seal 1 was installed. FIGs. 14A-B show the trenches performed in Manhattan, KS when the seal 1 was first applied (FIG. 14A) and after 8 weeks (FIG. 14B).

[0085] As a result, both the core testing and trial installations show compatibility of the seal 1 in various compositions, types, and ages of asphalts and pavements that are subject to varying environmental conditions. Seal 1, under both core testing and trial installations, did not show shoving or other distress to the asphalt or pavement. Moreover, the results indicated that the preformed sealant A typically used in concrete is, in contrast to seal 1, inadequate and destructive in asphalt and pavement applications.

[0086] The results also indicate that the modified Marshall test as created and used herein, can be used to determine if an asphalt or pavement is compatible or incompatible with a sealant, including seal 1 (and preformed sealant A showing incompatibility). Test results showing no sign of shoving can indicate good trench performance after the sealant is installed. The modified Marshall test can also be used to determine the maximum force allowed before pavement failure or, in other words, the amount of force that will induce shoving in the asphalt or pavement once a sealant is installed. Since the strength of material, such as asphalt, pavement, concrete, and the like, can depend on several variables such as age, level of compaction, composition, municipality, use, location, and environmental conditions, there is a need for a test to evaluate the material strength and suitability for a sealant prior to installation. The modified Marshall test addresses this need.

[0087] An installation machine and/or platform is contemplated to align the seal with the trench. This machine, platform or system can include a mechanism for compressing the seal so that it can be installed in the trench, a discharge blade that installs the seal, and a compaction wheel that ensures that the seal top flange is in intimate contact with the pavement surface. The installation machine includes a carriage for holding reels of seal that can be from 50 feet to

10,000 feet in quantity. [0088] With reference to FIG. 17A, 17B, and 18, as well as United States Patent Publication

US20100080653 Al (which is incorporated by reference), the aspects disclosed above can entail a continuous operation in which the seal is mechanically installed immediately after the foam has been placed. The apparatus 50 for installing the seal should include a guide mechanism 51 for aligning the seal with the trench opening in the proper orientation. Wheels or other mechanisms 53 compress the seal while discharge blade 54 places the seal in the trench opening. Final level of the seal in the trench is accomplished by a compaction wheel 55. The machine should include a locating device 52 to keep itself centered in the trench opening.

[0089] Ideally all the equipment would be installed in one platform 60. Fiber is placed in the trench at the beginning of the platform by way of spool or dispenser 61. Downstream from this operation, the foam backfill is deposited into the bottom of the trench by pumping mechanism 62. Finally, a spool or dispenser 63 places the seal so as to complete the reinstatement. The platform 60 should be flexible enough to allow for installation around turns and over changes in pavement elevation, possibly by employing a wheeled chassis 64. Notably, the sequence of operations on the platform 60 is significant, with fiber/utility dispenser 61 proceeding before (e.g., at the leading edge) and the seal placement mechanism 63 at the trailing edge. Foam pumps 62 may be interposed between these items, although a plurality of pumps could be provided before, in parallel with, or after (as shown in FIG. 18) the fiber/utility dispenser 61. Ultimately, the positioning and arrangement of pump(s) 62 should be made with an eye toward maximizing the speed at which foam is deposited and cures within the trench. Consideration as to the source of the foam (i.e., bulk kit, continuous addition, hand mixing, etc.) also influences the plumbing arrangement for platform 60.

[0090] Fig. 19 shows orientation of trailing edge 31a and leading edge 31b relative to the direction F of installation/unwinding (e.g., during the operation of system 50). As shown here, a diagonal cut is made through the top flange of the lead edge 31b, although s similar operation can be performed on the trailing edge 31a. Staple 35 is installed through portions of each edge 31a, 31b, with the understanding that the terminal edges (not visible) of the staple 35 are bent or crimped by the fastening implement to insure that the staple 35 is held in place within each member associated with edges 31a, 31b. In this manner, the separate seal members are coupled and move in concert along the line of installation F. Further, because conventional staples are immediately crimped and affixed as they are dispensed, the operator needs to create only a minimal amount of slack in the spool carrying the trailing edge 31b in order to couple the members together. That is, the speed of installation of staples avoids the need for adhesive seals to cure. As noted above, the fastening implement can even be integrated into the cutting tool so as to streamline and simplify the installation system. Further still, the simplicity of staples enables use of this arrangement in any number of disparate, existing trench forming platforms/ apparatus.

[0091] Figs. 20A and 20B show exemplary schematics for embodiments of the cutting tool (Fig. 20A) and how it might be implemented on a mobile platform (Fig. 20B). Handheld or freely manipulated tool 300 defines a channel or secure gripping slot 302 with flanges 304 on either side. A cutting blade 306 is affixed to one edge. Alternatively, a platform based tool 310 includes spaced apart blocks 314 defining the slot 312, with a blade 316 positioned proximately. Tool 310 is carried on a mobile platform 320 fitted with a T-shaped spool carrier 322.

[0092] In view of the foregoing, one aspect of the invention relates to a seal member for a micro trench. The seal member may be formed as a continuous web and positioned around a spool or reel. The seal member includes a top flange, a central body extending orthogonally down from a middle portion on an underside of the top flange, a plurality of protrusions extending radially away from the central body, and an engagement feature positioned at a lower terminal end of the central body. Additional aspects may include any one or combination of the following features:

• wherein the engagement feature has a triangular or V-shaped cross sectional profile; • wherein the top flange includes a central hinging groove formed on a top facing;

• wherein at least one of the plurality of protrusions each includes a hinging groove;

• wherein the plurality of protrusions extend radially away from the central body at a shorter radial distance than the top flange;

• wherein the plurality of protrusions include one or more pairs positioned at an identical axial height on opposite facings of the central body;

• wherein the pairs of protrusions each have a different radial extension, with a shortest radially extending pair positioned immediately next to the engagement feature;

• wherein the pairs of protrusions have progressively shorter radial extensions so that a longest radially extending pair is positioned immediately next to the top flange and the shortest radially extending pair is positioned immediately next to the engagement feature; and

• wherein the plurality of protrusions extend perpendicularly away from the central body.

[0093] A further aspect relates to a system for sealing a micro trench. This system includes all of the various aspects of the seal member identified in the previous paragraph, along with at least one selected from: i) an adhesive applied to a portion of the seal member, and ii) a curing foam used as a reinstating material. This system may also be provided on a mobile platform that is configured to transport and dispense the seal member and the foam/the adhesive. When the mobile platform is used, it may also have a guide mechanism, a discharge blade, a compaction wheel, and/or a plurality of storage tanks configured to mix a curing agent with the foam and/or the adhesive as it is dispensed. The system and mobile platform can both incorporate, either as a standalone member or as part of the guide mechanism or discharge blade, a cutting tool and fastening implement, wherein the fastening implement delivers a staple through the seal members. Any of these aspects of the system might also include one or a combination of the following: • wherein the foam is an elastomer configured to: i) flow around the seal member prior to curing and ii) adhere to the sealing member and any adjacent surface during and after curing;

• wherein the foam includes urethane and/or silicone;

• wherein the foam forms open or closed cell upon curing;

• wherein the foam has a cream time of 1-30 seconds, a gel time of 2-60 seconds, and a tack free time 3-120 seconds; and

• wherein, when cured, the foam has a core density of 0.5 - 60 pounds per cubic foot and a compressive strength of 2-200 psi.

[0094] Finally, a method for sealing and/or reinstating a micro trench is contemplated. The method includes forming a micro trench in a hardened surface at a first rate of speed and positioning a sealing member having any of the characteristics identified above to seal the hardened surface at a second rate of speed and wherein the second rate of speed is equal to or faster than the first rate of speed. Additional steps for this method might include: i) coating the seal member with an adhesive as the seal member is positioned within the trench and/or ii) providing an curable foam (having any of the qualities mentioned above) into the micro trench simultaneous to or immediately after the seal member has been positioned in the micro trench. When a curable foam is used, the additional step of mixing the foam composition with a curing agent as the foam is provided into the micro trench is a still further aspect of the method. The method might also involve providing the seal member by winding elongated strips of the seal member onto a plurality of spools so that a first spool feeds the seal member into the micro trench and, prior to the seal member being completely unwound from the first spool, splicing a trailing edge of the seal member from the first spool with a leading edge of the seal member wound on the second spool. [0095] The aforementioned systems are advantageous in comparison to those conventional systems in several regards. Foremost, the use of foam allows for the trench backfill operation to proceed at the same rate as the initial cutting of the trench. In contrast, conventional systems employing cementitious grout, sand, asphaltic material, or elastomeric patching (or some combination of these materials), result in a reinstatement rate of eight feet per minute. However, conventional cutting saws used to form microtrenches may proceed at twenty five feet per minute or higher. Thus, various disclosed aspects of the invention identified herein improves significantly upon previously known rates of reinstatement. In some aspects, the structures and methods contemplated herein enable the rate of reinstatement to match the rate of conventional cutting saws, thereby leading to faster installation, reduced traffic impairment, and reduced overall costs in comparison to the conventional reinstatement methods noted above.

[0096] What has been described above includes examples of the present specification. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the present specification, but one of ordinary skill in the art may recognize that many further combinations and permutations of the present specification are possible. Each of the components described above may be combined or added together in any permutation to define embodiments disclosed herein. Accordingly, the present specification is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim.