METHOD AND APPARATUS OF SEALING SEAMS IN SEGMENTED BRIDGES

A seal between abutting cement segments is provided, the cement segments each having a top surface, each top surface being substantially in the same plane. The seal comprises an epoxy adhesive in contact with the cement segment and a woven member The woven member comprises carbon fiber bundles, each of the bundles are bonded to the top surface of the cement segments.

FIELD

The present disclosure relates to the treatment of bridge and road surfaces and more particularly, to a method of sealing seams between bridge and road surface segments.

BACKGROUND

Segmented bridges have been used for many years as a cost effective and structurally sound bridge architecture. A typical segmented bridge may include pre-constructed bridge segments that are formed in predetermined lengths of for example 10 feet and full road widths of over 10 feet and more typically over 20 feet wide. The bridge segments are butted end to end and supported primarily by an interior cable system that runs through passages formed within the concrete bridge segments. A series of bridge segments comprise a bridge span that extends from one pillar to another. It is important to seal the seam that is created at the location where two bridge segments are butted together to prevent water from penetrating the seam and getting to the cable system where the water can cause corrosion of the support cables within the bridge segments. A prior method of sealing the seam has included cutting a groove along the upper surface of the bridge segments along the seam and filling the cut groove with an epoxy. However, the epoxy filled grooves are still capable of failure and it is desirable to provide a cost effective and improved method of sealing the seams between the bridge segments.

SUMMARY

The present disclosure provides methods and apparatus for sealing the seams between bridge segments or any other road segments. Methods can optionally include cutting a groove along an upper surface of the bridge or road segments along a seam and filling the cut groove with an epoxy. According to the present disclosure, the epoxy is applied on opposite sides of the seam and a fibrous material is applied to the surface so as to span over the seam for the length of the seam. According to still another aspect of the present disclosure, the surface of the bridge or road segments along the seam may be etched or otherwise cleaned in order to enhance the adhesive ability of the epoxy.

DETAILED DESCRIPTION

With reference toFIGS. 1-3, a portion of a segmented bridge10is shown including a first pre-constructed concrete bridge segment12and a second concrete bridge segment14that are shown butted together. The bridge segments12,14each include passages16formed therein that receive a cable system (cables18) that provides the primary support for the bridge segments12,14as they extend between spaced pillars50. A seam22is disposed between the bridge segments12,14. Optionally, a groove24can be cut or otherwise formed in the upper surface of the first and second bridge segments along the seam22. The groove24can be filled with an epoxy adhesive material26such as an epoxy, an urethane sealant, a silicone sealant or other suitable sealants or combinations thereof.

An epoxy or other suitable adhesive material26is then applied along the surface of the bridge segments12,14along the seam22and extending several inches therefrom. Preferably, the adhesive material26extends 2 to 12 inches in each direction on opposite sides of the seam22. A strip of fibrous material20is then applied to the adhesive material26along the length of the seam22. It should be noted that the adhesive material26may be applied to the fibrous material20or to the bridge segments12,14, or both. The fibrous material20can include fiber bundles32which may include carbon fibers, Kevlar fibers, fiberglass, carbon fibers, poly-parapheneylene tetraphthalamide, para-aramid nylon, aramid fiber, aromatic polyamide, and combinations thereof or other suitable man made and naturally occurring fibers that exhibit satisfactory strength and flexibility characteristics. The fibrous bundles32may be secured with a thread (not shown). The fibrous material20may include one or more threads28that are woven to desired densities to allow proper wetting of the material during application with the adhesive material26. The fibrous material20can also be precoated with the adhesive material26and pre-cured to provide a flexible, yet relatively rigid material that aids in application of the fibrous material20. It is desirable that the adhesive material26wets into the fibrous material20and/or the spaces between the transverse fiber bundles32to provide a fiber reinforced water resistant cover to the seam22.

As shown inFIGS. 6-7, examples are illustrated according to the present disclosure of the rigidified fiber mesh tape20, that can be used for sealing a seam22in a segmented bridge10. The rigidified fiber mesh tape20comprises a number of transverse fibers32running the distance of the width of the mesh tape106and a number of longitudinal fibers or threads28. The transverse fibers32run parallel to one another and are in tension. As best seen inFIG. 7, the longitudinal threads28can be woven into the transverse fibers32, the longitudinal threads28alternating from a position above the transverse fibers32to a position below the transverse fibers32. Alternatively, as best seen inFIG. 8, the longitudinal threads28sandwich the transverse fibers32. In other words, the longitudinal threads28can be layered on top and below the transverse fibers32, providing a fiber mesh100with a lower manufacturing cost. A further reduction of manufacturing cost may be achieved by providing only one of the layers of longitudinal threads28, either on top or below.

The transverse fibers32and longitudinal threads28may be of any cross-sectional shape, such as flat (ribbon like), rectangular, oval or round. In the same embodiments, the longitudinal threads28have a flat cross-section, as seen inFIGS. 7-9, providing a large surface area to contact the segments12and providing a low bending stiffness in the plane of the mesh tape20.

As shown inFIGS. 4-7, the longitudinal threads28are generally at 90-degree angles (transverse) to the transverse fibers32. In some embodiments, the longitudinal threads28may be at 45-degree angles to the transverse fibers32, or some angle between 45-degrees and 90-degrees. In a 45-degree fiber orientation, the longitudinal threads28tend to be loaded in tension along with the transverse fibers32.

In some embodiments, the transverse fibers32and longitudinal threads28may be spaced anywhere from over 1 inch apart to less than 1/32 inches apart so long as the spacing is sufficient to allow adhesive to flow between the fibers102,104, discussed herein. The rigidified fiber mesh tape20has a roughened surface28exposed or produced upon removal of a cover sheet24, as will be discussed in detail herein. In some embodiments, the transverse fibers32and/or the longitudinal thread28are made of pre-cured carbon, although any material providing flexibility and tensional strength may be used. Moreover, transverse fibers32and longitudinal threads28may be of different materials. For example, transverse fibers32may be Kevlar or bundles of Kevlar and longitudinal threads28may be a nylon or a nylon blend. Other examples of transverse fibers32include carbon fibers, poly-parapheneylene tetraphthalamide, para-aramid nylon, aramid fiber, aromatic polyamide, and combinations thereof. In some embodiments, transverse fibers can be in bundles or individual fibers. Other examples of longitudinal threads28can include nylon, polyester, polypropylene, nomex, cotton, carbon fibers, poly-parapheneylene tetraphthalamide, para-aramid nylon, aramid fiber, aromatic polyamide, and combinations thereof.

In some embodiments as shown inFIG. 6, the adhesive material26(discussed above) is applied to the first surface36of the rigidified fiber mesh tape20and a thin layer or at least some of the adhesive material26remains on the surface36of the rigidified fiber mesh tape20. It should be noted that the openings between the transverse fibers32and longitudinal threads28remain unobstructed.

As discussed herein, to provide a strong bond between the rigidified fiber mesh tape20, it is important to have the surface of the rigidified fiber mesh tape20clean and roughed. In order to keep the surface clean and provide a roughened surface, over the layer of adhesive material26, on the surface36(and optionally on the surface38), is applied a flexible cover sheet30of impermeable sheet or film comprising textile, nylon, a polymeric or plastic material. The side of the cover sheet30in contact with the adhesive material26preferably exhibits a texture, such as a woven texture surface39. The carbon fiber13or rigidified fiber mesh tape20, with the adhesive material26and the cover sheet30applied, are subject to high temperature and pressure, via known techniques, allowing the adhesive material26to cure. Once the adhesive material26has cured, the result is a rigid carbon fiber sheet or rigidified fiber mesh tape20having a removable cover sheet30covering one or both surfaces thereof. This rigid carbon fiber sheet or rigidified fiber mesh tape20may then be cut or sawn into the desired sizes. In this form, the rigidified fiber mesh tape20can be stored and/or shipped to a job site for use. With the rigidified fiber mesh tape20, the resin applied during the manufacture of the open fabric tends to fill the window between the mesh. When the textured cover sheet is removed, these windows remain adhered to the cover sheet and leave the openings clear. Thus, the cover sheet provides both a roughened surface, but also open windows.

At the job site, the cover sheet30prevents dirt, grease and other debris from coming into contact with the rigidified fiber mesh tape20. Immediately prior to use, the cover sheet30is removed, or more accurately peeled away, from the surface36of the carbon fiber strip or rigidified fiber mesh tape20leaving exposed a clean roughened surface38. This roughened surface38is a result of at least two factors, individually or in combination. First, the textured surface39of the cover sheet30causes an impression to be formed in the adhesive material26on the surface36as it cures. Second, as the cover sheet30is removed from the mesh tape20, some of the adhesive material26remains adhered to the plastic sheet30and breaks away from the rigidified fiber mesh tape20.

With the method of the present disclosure, a cost effective and improved method of sealing the seams between bridge segments is provided. It is noted that the sealing method of the present disclosure may also be utilized on road or other bridge surfaces in which grooves or seams are often cut between large concrete or asphalt sections or when road sections are being patched. The use of an adhesive/fibrous seal along the seams between non-movable road or bridge surface sections can prevent the intrusion of water that can cause further cracking along the seams especially in colder climates.

As illustrated in the drawings, the rigidified fiber mesh tape20can be pre-cut and can be provided in suitable lengths for their intended use. As will be appreciated by those skilled in the art, a large sheet may be cut to the required sizes before adhering it to reinforce a structural element12. In some embodiments, the fiber mesh tape20can be stored and/or shipped in rolls. In some embodiments, a fit can include adhesive material26, mesh tape20and cover sheet30, as illustrated inFIG. 8. In some embodiments, the fit can include a cutting tool for cutting mesh tape20into desired shapes.