US2402408A - Suspension bridge saddle - Google Patents

Description

June 18, 1946. s. JOHNSTON SUSPENSION BRIDGE SADDLE Filed Oct. 22-, 1943 2 SheetsSheet 1 i Hunhunum iiiililu llllllJllllllL June 18, 1946. v s. JOHNSTON. 2,402,408

SUSPENSION BRIDGE SADDLE.

Filed Oct 22, 1945 '2 Sheets-Sheet 2 Patented June 18,

UNITED, :sTATEs F PATENT OFFICE v I 2.402.408 v t suspens on BRIDGE SADDLE 'jS terling Johnston, Bethlehem, Pa., assignor to Bethlehem- Steel Company, acorporation of P n l ania Application :Qetober 22, 1943,"Serial No. 501,242

This invention relates dies for suspension bridge cables of the'open" type. construction.

This type .of cable, which for suspension bridges 'ofcomparatively short spans, comprises a plurality of spaced strands or ropes which are :placed. far enough apart to allow for. inspection and painting. To effectively support the cable it is preferable to provide a saddle with definitely spacedgroo'ves therein for each individual strand. Where the cable is made of a considerable number of strands it is customary to provide a saddle with grooves which are arranged to support a plurality of the strands in tiers. Heretofore the radii for all of the tiers of strands usually originated from a common center. This arrangement necessitated a different structure for each tier.

The present invention provides a saddle made up of a plurality of substantially identical members which are preferably made as finished castings requiring no expensive machining. These members can be constructed so that when angularly assembled as a saddle the radius of the ropes supported thereon in each tier is substantially the same.

In the accompanying drawings- Figure 1 is a side view of the structure showing the saddle members supporting three vertical tiers of strands with a part of the outer web plate broken away.

Figure 2 is a cross sectional view on line 2-2 of Figure 1.

Figure 3 shows one of the individual strand supporting castings on a somewhat larger scale.

Figure 4 is a cross sectional view on line 4-4 of Figure 3.

Figure 5 is a view similar to Figure 4 but of a modified form of strand support using a twin type casting.

Figure 6 is a diagrammatic view of the saddle members indicating their relative locations in the structure.

Referring to the drawings more in detail, I designates a tower, having a cap plate H supported on the top thereof, to which spaced web plates l2 and I3 are attached by welding or other means. Mounted intermediate the web plates '2 and I3 are the saddle members H which are pref erably provided with arcuate seats l to support the cable strands (or ropes) l6. Bolts I! are provided to secure the saddle members l4 in their assembled relation with the web plates l2 and I3. Each of the bolts l1 extends through all of the web plates l2 and I3 through a plurality of to improvements in sadmay be well adapted the members HI and 2 I v provides support for these members M as well as furnishing means for the transfer of the loadfrom the saddle members to the web plates. The bolts l'l also serve as tension members for clamping the entire assembly compactly together. Stifi'ener plates l8 which are attached to web plates. I2 and cap plate'H give additional lateral support to the saddle structure.

By terminating the seats l5 short of the ends of r the members M a more uniform structure is provided for the strands l6 as these strands will frictionally engage the entire surface of the seats IS. The groove 24 requires no machinefinishing, the natural surface of the casting being suihciently smooth so that it will not cause injury to the strand. The bolt holes 25 are spaced so that the saddle members are reversible end for end.

In Figure 5 a "twin type saddle member H4 is shown. With this type of construction a plurality of strands, instead of a single strand, in each tier may be supported between two web plates H2 and H3, thus reducing the number of web plates required while providing adequate support when the strands are of relatively small size.

The arrangement of the bolt holes 25' in the web plates for the bolts I! as specifically shown in Figure 6 is an essential feature of my invention. The arrangement permits a plurality of saddle members I 4 to be supported by means of the bolts H in such a relative position that the seats l5 form a continuous arc. The bolt holes when thus located on the arc of circles with equal radii rl r2 and r3 will so position the saddle members l4 when they are assembled with web plates through the medium of the bolts N that the seats l5 of the saddle members ll of each tier will lie in a continuous are, as shown in Figure 1.

While I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes andmodifications without departing from the spirit thereof and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A saddle comprising a plurality of assemblies arranged in tiers for supporting individual strands of a bridge cable, each of the assemblies comprising identical units angularly disposed to each other to provide a support of substantially the same radius for thestrand irrespective of its location in the saddle.

2. A cable support comprising vertical web plates and saddles, said saddles comprising a plu,

rality of arcuate strand supporting assemblies disposed intermediate the vertical Web plates-the.

units of said assemblies being angularly disposed to each other to provide supports with identical radii for the strands irrespectiveof .the, location 1;;

of the strands in the structure and means for positioning each assembly,

3. A cable support comprising parallel vertical web plates and saddles, said-saddles comprising. a plurality of identical assemblies for supportingv the individual-strands of a bridgecable, each as-x sembly consisting of castings disposed at an angle to. each Other and having I arcuate surfaces for supporting at least-one of said strands and means for attaching said castings-to the parallel web plates; so that each assembly is supported in spaced relation to: the adjacent assemblies,

4.:A bridge cable support comprising ia-plurali-ty; of spaced vertical members and-a plurality "intermediate the vertical web plates, each of said saddles comprising a plurality of arcuate strand supporting units angularly disposed to each other to provide supports'with identical radii for the strands irrespective of the location of the strand in the structureand means intermediate, and

-positionedlby,: the; web plates for independently s pp rting each assembly.

*6; 'A cable support comprising parallel vertical web plates and saddles, said saddles comprising a plurality of identical assemblies'for supporting the individual-strands of a bridge cable one above another, each assembly consisting of units disposed at an angle to each other andhavlng arcuatel-surfaces-for supporting-at least one of said strands and means for attaching said units to the 'parallel web plates so that'each unit is supported independently of any other unitlying at a different level in thestructure.

STERLING JOHN'STQN.

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