US3788758A

US3788758A - Hold-down assembly for modular expansion joints

Info

Publication number: US3788758A
Application number: US00241990A
Authority: US
Inventors: C Scheffel
Original assignee: Fox Industries Inc
Current assignee: Fox Industries Inc
Priority date: 1972-04-07
Filing date: 1972-04-07
Publication date: 1974-01-29
Anticipated expiration: 1991-01-29

Abstract

A new and improved hold-down assembly is provided for attachment to modular expansion joints. These expansion joints are used to connect sections of bridge roadways. The hold-down assemblies secure the joint in such a manner as to allow for movement due to expansion, contraction, and rotation and additionally eliminate the noise produced by the joint which is generated by the traffic flow. The hold-down assembly consists of a thin strip of stainless steel which is bonded to the underside of a supporting bar for the joint. The supporting bar makes contact with a plurality of fabric reinforced elastomeric pads topped wtih thin sheets of teflon. The hold-down assemblies are attached to the joints members by means of welded flanges and appropriate hardware.

Description

United States Patent [191 Scheffel Jan. 29, 1974 HOLD-DOWN ASSEMBLY FOR MODULAR EXPANSION JOINTS Carl W. Scheffel, Ellicott City, Md.

[73] Assignee: Fox Industries, Inc., Baltimore, Md.

[22] Filed: Apr. 7, 1972 [21] Appl. No.: 241,990

[75] Inventor:

[52] US. Cl. 404/56, 52/573 [51] Int. Cl. E01c 11/10 [58] Field of Search... 52/573; 14/16; 94/18; 404/56 [56] References Cited UNITEDSTATES PATENTS 3,482,492 12/1969 Bowman 14/16 3,484,882 12/1969 Blanchette 14/16 Primary Examiner-John E. Murtagh Attorney, Agent, or FirmWalter G. Finch [5 7] ABSTRACT A new and improved hold-down assembly is provided for attachment to modular expansion joints. These expansion joints are used to connect sections of bridge roadways.

The hold-down assemblies secure the joint in such a manner as to allow for movement due to expansion, contraction, and rotation and additionally eliminate the noise produced by the joint which is generated by the traffic flow.

The hold-down assembly consists of a thin strip of stainless steel which is bonded to the underside of a supporting bar for the joint. The supporting bar makes contact with a plurality of fabric reinforced elastomeric pads topped wtih thin sheets of teflon. The hold-down assemblies are attached to the joints members by means of welded flanges and appropriate hardware.

8 Claims, 4 Drawing Figures PMENIH] JAN 2 91974 sum 1 or z HOLD-DOWN ASSEMBLY FOR MODULAR EXPANSION JOINTS This invention relates generally to expansion joints that are used to connect sections of bridge roadways, and more particularly it pertains to hold-down devices designed to be used on expansion joints.

A modular expansion type of connector consists generally of plurality of metal beams, cushioned by formed neoprene compression seals, and supported on bars in such a manner as to allow for expansion, contraction and rotation of the joint. This expansion joint has proven successful. However, there is a high level of noise produced by the metal-to-metal contact of the expansion joint as traffic moves over it.

It is the object of this invention, therefore, to provide a hold-down device to be attached to an expansion joint that will eliminate objectional noise but will allow for such movement as necessary for expansion and contraction of the joint.

Still another object of this invention is to provide a hold-down device designed for use with expansion joints for sections of bridge roadways which is econom ical to manufacture, efficient and reliable in operational use, and which is easy to install and maintain.

Other objects and attendant advantages of this invention will become more readily apparent and understood from the following detailed specification and accompanying drawings in which:

FIG. 1 is a cross sectional elevation and view of a conventional Acmaseal modular expansion joint, incorporating the hold-down assemblies of this invention installed thereon;

FIG. 2 is a cross sectional elevation view taken along line 2-2 of FIG. 1;

FIG. 3 is a cross sectional plan view taken along line 3of FIG. 1; and

FIG. 4 is a cross sectional elevation view taken along line 44 of FIG. 1.

Referring now to FIG. 1, there is shown a cross sectional end view of a conventional modular expansion joint 10. This joint includes

metal channels

16, 18, 20, 22, and 24 which run the width of a roadway. These metal channels l6, 18 20, 22 and 24 are cushioned by formed neoprene compression seals 28. I

The

channels

20, 22, and 24' together with the seals 28 rest on top of support bar 30. A low friction wear strip 32 is bonded onto the top of the support bar 30, and it contacts the

channels

20, 22, and 24.

A plurality of hold-

down assemblies

12, 14, and are incorporated into the expasnion joint 10. Each hold-down

assembly

12 and 14 consists of a thin strip 34 of gage stainless steel, covering and bonded to the bottom of the support bar and flanges 36 having slots 38 therein welded onto the two sides of the support bar 30.

The support bar 30 rests upon a plurality of fabric reinforced elastomeric pads 40 with a one thirty-second inch thick sheet 42 of polytetrafluoroethylene, i.e. Teflon bonded onto their tops, which contacts the surface of the stainless steel strip 34. The pads 40 are mounted onto the

channel members

16 and 18, in one of the two alternate versions of the hold-

down assemblies

14 and 15 shown in FIGS. 1, 2, and 3, of the drawings.

In the one alternate holddown assembly 14 shown in FIGS. 1, 2, and 3, the following is performed on both sides of the support bar 30. A wedged shape shim plate 44 is welded at 46 onto the channel 16 to provide a level area for welding on the surface 48 of the threaded coupling 52, and also for bonding the pad 40 thereon.

A hex head bolt 50 is passed through the slot 38 into the coupling 52. The bolt 50 is finger-tightened and then tack welded, thus securing the hold-down assembly 14 but allowing movement for expansion and contraction.

In the other alternate hold-down assembly 15 the following is performed on both sides of the support bar 40. A wedged shaped plate 44 is welded at 46 onto the channel 18 to provide a level area for bonding the pad 40 thereon. A flat head bolt '54 is passed through a countersunk hole 56 on channel 18 up through the slot 38 in the flange 36 and secured by a nut 58. The nut 58 is finger-tightened and then tack welded.

A pad 40 is also positioned under the center section of the support bar 30, and it is bonded to and held in place by a bracket 158, supported on each end by a stud 60. The studs 60 are welded at 62 to the center channel member 22 and secured by a nut 64.

It is to be noted that this expansion joint 10 can have an optional plurality of channel sections to fill the requirements, of each installation. However, the principle of the hold-down devices or assemblies 12, 14, and 15 remain the same. I

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In combination with an expansion-contraction type modular joint used to connect sections of bridge roadways consisting of a plurality of parallel spaced channels which run substantially the width of a roadway, compression seals positioned between certain of said parallel spaced channels to form expansion and compression joints, and supporting members positioned transversely of said parallel spaced channels for supporting said parallel spaced channels; and a plurality of spaced hold-down assemblies, each said holddown assembly being fully contained within said modular joint and having a portion coupled to its respective channel and a spaced portion being coupled to said supporting member for holding together its respective channel and said supporting member from within said modular joint and mounted for movement to and between its respective channel and supporting member to permit relative movement between said channels and supporting members and thereby eliminate noise but allow for movement as necessary for expansion and contraction of said modular joint.

2. In the combination as recited in claim 1, each said hold-down assembly consisting of a stainless steel rub sheet, a fabric reinforced elastomeric pad having a polytetrafluoroethylene top adjacent said steel rub sheet, said pad being attached to its respective channel, and means for coupling said teflon topped pad to its respective supporting member.

3. In the combination as recited in claim 2, wherein said stainless steel rub sheet is positioned below and adjacent to its respective supporting member and having the polytetrafluoroethylene topped elastomeric pads positioned under the respective supporting members.

4. In the combination as recited in claim 1, and a slotted flange secured to each side of a supporting merriber, a studded element secured to a selected channel,

closure which precludes entry of foreign matter therein.

7. In the combination as recited in claim 1, wherein said h0lddown assemblies are located at points precisely where said channel is urged into engagement with said support members.

8. In the combination as recited in claim 1, wherein at least one of said channels is a center channel positioned on said supporting members and having at least one hold-down assembly which holds for relative movement said channel with said support members.

Claims

1. In combination with an expansion-contraction type modular joint used to connect sections of bridge roadways consisting of a plurality of parallel spaced channels which run substantially the width of a roadway, compression seals positioned between certain of said parallel spaced channels to form expansion and compression joints, and supporting members positioned transversely of said parallel spaced channels for supporting said parallel spaced channels; and a plurality of spaced hold-down assemblies, each said hold-down assembly being fully contained within said modular joint and having a portion coupled to its respective channel and a spaced portion being coupled to said supporting member for holding together its respective channel and said supporting member from within said modular joint and mounted for movement to and between its respective channel and supporting member to permit relative movement between said channels and supporting members and thereby eliminate noise but allow for movement as necessary for expansion and contraction of said modular joint.

4. In the combination as recited in claim 1, and a slotted flange secured to each side of a supporting member, a studded element secured to a selected channel, and means for moveably securing said slotted flange and studded element.

5. In the combination as recited in claIm 1, wherein each said hold-down assembly comprises, a support bar which is secured to its respective channel, a flange extending from and fixedly secured to said support member adjacent to and spaced from said support bar, and means coupled to and between said support bar and flange for holding said support member and channels in engagement.

6. In the combination as recited in claim 1, wherein the hold-down assemblies are contained within an enclosure which precludes entry of foreign matter therein.

7. In the combination as recited in claim 1, wherein said hold-down assemblies are located at points precisely where said channel is urged into engagement with said support members.