US20080250579A1

US20080250579A1 - Modular Support Catch System

Info

Publication number: US20080250579A1
Application number: US12/099,966
Authority: US
Inventors: Oded Sten; Kurt G. Conti
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-04-10
Filing date: 2008-04-09
Publication date: 2008-10-16
Also published as: WO2008124753A1

Abstract

A removable support structure for attachment underneath a bridge is provided. The removable support structure has one or more pre-assembled platform modules. Each module comprises an underlying grid and one or more panels attached to the top of the underlying grid. The modules are attached to, suspended below, or otherwise supported beneath the underside of a bridge. The underlying grid is constructed from substantially parallel beams and lateral supports perpendicular to the beams connecting the parallel beams.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application No. 60/922,665, filed Apr. 10, 2007, the entirety of which is hereby incorporated by reference into this application.

BACKGROUND OF THE INVENTION

1. Field of The Invention
The present invention relates to bridges. More particularly, the present invention relates to temporary work platforms and debris collection/prevention system installed under bridges.
2. Description of Related Art
When replacing, repairing or otherwise working on a bridge deck, one of two types of systems is generally used. The first type of system, sometimes referred to as “catches,” is systems installed underneath the bridge deck. A “catch” is a protective layer or layers that typically sits or is directly inserted a few inches under the bridge deck. Catches are typically supported by the existing bridge structure and installed underneath the bridge-deck to catch all of the debris, such as chunks of concrete, that may fall when the bridge is being worked on from the top side of the bridge deck. A typical catch is installed by positioning woodlegging between the stringers (steel beams directly underneath the bridge deck). When concrete is either poured or removed from the bridge deck, the catches keep the debris from falling on the ground, traffic or water below the bridge. Once the work is complete, the wood is removed and reused or scrapped, as its condition dictates.
A different system is often used when work needs to be done by workers who have to be underneath the bridge to perform it. Scaffolding systems are installed underneath bridges to support the weight of the workers moving on the underside of the bridge deck. These so-called scaffolding systems are typically much lighter and the weights that they can hold are much less than the typical debris catch system. Thus, one drawback is that such scaffolding systems oftentimes cannot function as a reliable catch system.
Additionally, these scaffolding systems are designed to be built or erected entirely up in the air under the bridge. Some of these systems are assembled using short sections. Others are suspended over tightly spaced horizontal cables. Installing such systems is labor intensive and time consuming, and therefore expensive. Moreover, since they are built relying on the bridge structure, they might not be reusable for other jobs. Additionally, because they are typically made using short sections, or suspended over horizontal cables there are typically numerous vertical supports for a relatively small work surface. As a result, open mobility and efficiency of the workers is reduced, increasing the labor cost of the operations in which they are engaged. Lastly, the large number of vertical supports that is required, restricts the nature of the repairs that could be performed to the bridge while such systems are suspended underneath it.
What is needed is a support system that overcomes the many drawbacks of the prior art systems.

SUMMARY OF THE INVENTION

A debris catch and support system that provides flat, large work surface under a bridge or other deck is provided. The work surface is larger than commonly available existing systems. The modular catch system is sturdy enough to function as a catch, and also stable so that workers can confidently work on the surface, thereby increasing their productivity. The surface can easily support the typical equipment needed for bridge work such as ladders, compressors, power generators and if needed even a small manlift.
The catch and support system is modular so that all of the assembly except for its actual attachment to the bridge structure can be done on the ground underneath the bridge or beside the bridge or some other location off-site. Because the system is modular, the individual modules can be removed from the bridge intact. Once removed from a bridge, the same modules can be re-used on the same or different bridges. The re-use of such modules represents a significant economic advantage to known systems which generally are constructed on a bridge.
In one aspect, a removable catch and support structure for attachment underneath a bridge is provided. The removable catch and support structure has one or more pre-assembled platform modules. Each module comprises an underlying grid and one or more panels attached to the top of the underlying grid. The modules are attached to or otherwise suspended below the underside of a bridge. The underlying grid is constructed from substantially parallel beams and lateral supports perpendicular to the beams connecting the parallel beams.
In another aspect, a method for installing a temporary catch and support structure on the underside of a bridge is provided. The method is performed by assembling one or more platform modules wherein each platform module comprises an underlying grid and one or more panels attached to the top of the underlying grid. The platform module is raised to a position underneath the bridge and attached to or otherwise suspended below the underside of the bridge. Optionally, additional modules are secured to the bridge and to each other to form a larger work surface under the bridge.
In one embodiment the modular platforms are raised using a crane and a carrier platform wherein the crane is positioned on top of the bridge deck, the carrier platform is attached to the crane by cables, and the platform modules rest on the carrier platform.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an embodiment of the underlying grid of the invention.

FIG. 2 illustrates a side view of a module suspended below a bridge.

FIG. 3 illustrates an underlying grid with panels to form a module.

FIG. 4 illustrates a side view of a lateral support attached to an I-beam.

DETAILED DESCRIPTION

A removable catch and support structure for attachment underneath a bridge is provided. The structure is made up of one or more platform modules that, unlike prior art structures, are pre-assembled prior to being raised and secured to the underside of the bridge. The modules are preferably constructed of an underlying grid with one or more panels attached to the top of the underlying grid. The pre-assembled module is raised from the ground, barge, or other vehicle positioned under or above the bridge and secured to the underside of the bridge using techniques known in the art.
Referring to FIG. 1, in one embodiment an underlying grid 10 is constructed of a plurality of horizontal beams 14 that are substantially parallel to each other and connected by a series of lateral supports 18. The lateral supports 18 are positioned substantially perpendicular to the beams 14 and connect adjacent horizontal beams 14 to form the underlying grid 10. Panels 22 are attached to the top of the grid 10 to provide a work or catch surface for the module 1.
Preferably, the beams 14 are I-beams and more preferably the beams 14 are structural steel I-beams. The beam could be made of other material or in other shapes however. FIG. 1 shows a grid 10 with nine beams 14, but more or less beams 14 could be used. In one embodiment, the beams 14 are preferably positioned about 8 feet apart; however, the beams can be spaced farther apart or closer together. The beams 14 in one embodiment are between about 19 to 22 ft. in length. Again, the beams can be longer or shorter as discussed below. The type and number of beams 14 used, the spacing of the beams 14, and the length of the beams, will all depend on the specific application for which the modules are being assembled. Other materials however, such as metals or composite materials, or even wood could be used. The beams could be in other shapes as well, such as tubes, channels, etc.
The number of horizontal beams 14 used in a module 1 may depend on what part or portion of the bridge 100 is going to be worked on and how the modules I will be arranged under the bridge 100. For example, in one embodiment, as illustrated in FIG. 2, nine horizontal I-beams 14 are used that are spaced approximately 8 ft. apart to form a module 1 that is about 64 ft. across, which corresponds to half the width of the bridge 100 for which it will be used. The module 1 is positioned so that the length of the module 1 extends across the entire half of the bridge 100. The horizontal L-beams 14 of the module 1 are attached to the bridge 100 by way of vertical supports 28 (discussed below). The horizontal I-beams 14 of the module 1 are attached to the bridge 100 by way of vertical supports 28.
Optionally, additional modules I (not shown) can be connected to the ends of the already attached modules to form a support structure with greater surface area. The choice to proceed with attaching more modules will be entirely dependent on how much surface area is required.
Alternately a single grid 10 can have more than nine beams 14. For example, the module I of FIG. 2 can have double the number of beams forming a grid that is approximately 128 feet in length, which corresponds to the entire width of bridge 100. Conversely, the grid 10 can have less than nine beams 10 if a shorter module 1 is required. The orientation can also be fashioned depending on the application. For example, the beams 14 could be aligned longitudinally to the bridge length, or perpendicularly, depending on the need, dimensions and application.
The spacing of the beams 14 will primarily depend on the strength of the panels 22 and the permissible deflection limits of the specific application. In a preferred embodiment, panels are constructed of fiberglass reinforced polymers, such as Composolite® manufactured by Strongwell. Referring to FIG. 3, a series of approximately 8 ft Composolite® panels secured to the tops of the flanges of two I-beams separated by 8 ft will have minimal deflection and provide a sturdy workplace for both workers and equipment, and have sufficient strength to function as a catch for falling debris from work being done to the bridge deck. Other materials such as for example, plywood or corrugated metal, steel plates or decking, of various dimensions may be used for the panels depending on the intended function of the installed modules 1.
The length of the beams 14 in one embodiment is in the range of about 19 to 22 ft.; however, shorter or longer beams may be used. In one embodiment, 22 ft. W14×30 I-beams made of structural steal are used within the limits of permissible deflection. For grids 10 with longer beams 14, stronger beams may be required to maintain deflection within permissible limits. Other materials and types of beams may be used so long as they provide the requisite strength for the specific application.
Lateral supports 18 connect and secure the beams 14 in place to form the grid 10. In one embodiment, the lateral supports 18 are iron pipes, preferably 3 inch pipe sched. 40. However, a narrower or wider gauge pipe, or other material could be used. Pipes are preferred in some embodiments because of the high availability, low cost and high productivity in assembly. The pipes 18 can be attached to the I-beams 14 using a variety of techniques including attaching a stiffening plate to the I-beam, typically by shop welding, and attaching the pipe to the stiffening plate with W and C shapes or cotter pins. In the preferred embodiment, as shown in FIG. 4, the I-beam 14 is constructed with a 4 in. pipe sleeve 33, secured to the I-beam with a stiffening plate 36. The pipe sleeve 33 is dimensioned to receive the 3 inch pipe 18. The pipe 18 is fitted in the sleeve and secured to the sleeve using safety cotter pins 39.
One advantage of using the pipe/pipe sleeve framing assembly is that it permits quick assembly without sacrificing stability of the grid 10. In the example shown in FIG. 1, four lateral supports are provided to secure adjacent beams. This configuration yields modules of sufficient strength structural integrity that, when installed, and covered by Composolite® provide a surface strong enough to support workers and function as a catch. More or less pipes may be used depending on the application and still achieve a functioning module.
Additionally, different types of lateral supports 18 may be used, so long as the lateral supports function to secure the beams and form a grid 10.
The panels 22 are secured to the grid 10 to form the surface of the module 1. The panels 22 can be constructed of a variety of materials in a variety of shapes. Also, the panels 22 can be secured to the grid 10 in any way that will provide a secure attachment of the panels 22 to the grid. The manner in which the panels are attached to the grid may depend on the materials used for the panels or the materials used for the beams. Additionally, the intended use for the module may also be a factor in the choice of material for the panels 22.
In one embodiment 3 in. thick by 24 in. wide and 8 ft. long Composolite® fiberglass building panels are attached to the flanges of adjacent I-beams 14 of the grid 10. The panels can be attached to the I-beam by many means including but not limited to a lockwasher with a nut, and/or bonding gel or tackweld. The panels 22 are positioned in series so that preferably there are small gaps between adjacent panels. For many applications, small gaps are actually preferred, because gaps prevent water, snow, or ice from collecting on top of the module, eliminating weight as well as safety concerns. In many applications it will be important that there are no gaps between the panels so that nothing falls through the module, however, the precise positioning of the panels will depend on the specific application. The Composolite® panels are particular useful because they are lightweight but provide the strength necessary to function as a catch, they can be manufactured with a non-skid surface, and are durable enough to be used more than once.
Optionally, vertical rail posts 42 are included on all or part of the perimeter of the module. A railing system (not shown) can be constructed using the vertical posts in ways known to those skilled in the art. Railing can be assembled to meet safety requirements. Rails for example can be made from wire rope, wood timber, steel piping/tubing, or composite materials.
The modules I can be assembled anywhere prior to being raised and secured to the bridge. In one embodiment, the modules are assembled on site, below the bridge on which it is to be secured. In another embodiment, the modules are assembled off-site and brought on-site pre-assembled.
Once assembled and put in position under the bridge, the modules 1 are raised into position, as discussed below, and secured to or otherwise attached, suspended or rested below the underside of the bridge. The modules can be attached to the underside of the bridge using techniques well known in the industry. For example, vertical supports, generally wire ropes or rods, are attached to the outer beams of the modules. The vertical supports are then attached to the underside of the bridge. Non-limiting examples include the use of beam-flange connectors. In practice, the type of connection or attachment means used to attach the module to the bridge depends on the type of work being done on the bridge. For example, a module or modules can be suspended from the deck stringers, floor beams, main girders or resting on the bridge's pier caps.
The module or modules only need to be attached to the bridge at points along the perimeter of the module. One advantage of using modules in accordance with the present invention is that vertical supports are not required except along the perimeter of the module. As a result, installation of modules provides a much larger workspace that is unobstructed by vertical connectors, which allows workers to move more freely under the bridge than prior art platforms. For example, the module describe in FIG. 1 is approximately 22 feet by 64 feet. When secured to the bridge, there is a much larger workspace than the prior art systems which typically have vertical supports every eight or sixteen feet.
The position at which the modules are attached under the bridge depends on the particular application. A single module may be used if it provides adequate workspace for the particular application. Alternately more than one module can be hung to provide a larger platform. Multiple modules may be attached directly next to other modules to provide a continuous platform, or multiple modules can be hung at different positions under the bridge to provide separate platforms.
In another aspect of the invention, the modules are raised from a position on the ground or from the river to a position under the bridge deck in order to be secured to the bridge deck. Prior art systems are assembled and built in the air directly under the bridge deck. Because the modules of the invention are pre-assembled, they must be raised into position in order to be secured to the bridge deck.
In some configurations, the assembled modules may not be able to be directly raised to the desired height without additional support or bracing. For example, when pipes are used for lateral supports, the pipes do not provide enough rigidity to allow the module to be raised directly by a crane. In one embodiment, an assembled module that cannot be directly raised by a crane is placed on a separate carrier platform. The carrier platform is attached to a crane positioned on the bridge deck by way of cables. The cables are typically attached to the four corners of the carrier platform; however, any arrangement that will permit the raising of the carrier platform is acceptable. The carrier platform is then raised to the desired height with the module resting on it, and the module is then attached to the bridge. The carrier platform can then be lowered to receive and raise another module as needed.
The carrier platform can be constructed of any material in any configuration that will support the module as it is raised and attached to the bridge. For one example, the carrier platform is constructed of 1beams creating a ladder-shaped grid made out of structural steel. The crane is positioned on the deck of the bridge. Four cables are attached to the four corners of the carrier platform, which are then attached to the crane. The cables can extend down from the crane on the outside of the bridge; however, it may be necessary to extend the cables through holes cored in the bridge deck.
There will be various modifications, adjustments, and applications of the disclosed invention that will be apparent to those of skill in the art, and the present application is intended to cover such embodiments. Accordingly, while the present invention has been described in the context of certain preferred embodiments, it is intended that the full scope of these be measured by reference to the scope of the following claims.

Claims

1. A removable debris catching and support structure for attachment underneath a bridge comprising;

one or more pre-assembled modules wherein each module comprises an underlying grid and one or more panels attached to the top of the underlying grid; and

a means for securing the one or more modules to or below the underside of a bridge.

2. The support structure of claim 1 wherein the underlying grid is comprised of a plurality of substantially parallel beams and a plurality of lateral supports perpendicular to the beams connecting the parallel beams to form the underlying grid.

3. The support structure of claim 2 wherein the parallel beams are I-beams.

4. The support structure of claim 3 wherein the I-beams are comprised of structural steel.

5. The support structure of claim 3 wherein the grid has at least 5 parallel beams.

6. The support structure of claim 3 wherein the I-beams are spaced about 8 feet apart.

7. The support structure of claim 6 wherein the I-beams are 15 to 25 feet in length.

8. The support structure of claim 2 wherein the lateral supports are pipes or rods.

9. The support structure of claim 2 wherein the panels substantially cover the entire top of the support structure.

10. The support structure of claim 9 wherein the panels have a length that corresponds to the distance from the center of one I-beam to the center of the adjacent I-beam.

11. The support structure of claim 8 wherein the I-beams have pipe sleeves extending perpendicular from the beam dimensioned to receive the pipe or rod.

12. A method for installing a temporary support stricture on the underside of a bridge comprising the steps of;

i) assembling one or more platform modules wherein each module comprises an underlying grid and one or more panels attached to the top of the support grid;

ii) raising a platform module to a position underneath the bridge;

iii) securing the platform module to the underside of the bridge; and optionally iv) repeating steps ii) and iii) one or more times.

13. The method of claim 12 wherein the one or more platform modules attached to the underside of the bridge in step iv) are also attached to a platform previously attached to the underside of the bridge.

14. The method of claim 12 wherein the platform modules are raised in step ii) using a crane and a carrier platform wherein the crane is positioned on top of the bridge deck, the carrier platform is attached to the crane by cables, and the platform modules rest on the carrier platform.

15. The method of claim 12 wherein the grid is comprised of a plurality of substantially parallel beams and a plurality of lateral supports perpendicular to the beams connecting the parallel beams to form underlying grid.

16. The method of claim 15 wherein the parallel beams are 1-beams.

17. The method of claim 16 wherein the grid has at least 5 parallel beams.

18. The method of claim 15 wherein the lateral supports are pipes or rods.

19. The method of claim 18 wherein the I-beams have pipe sleeves extending perpendicular from the beam dimensioned to receive the pipe or rod.