US2294582A

US2294582A - Paving block

Info

Publication number: US2294582A
Application number: US304356A
Authority: US
Inventors: Francis C Sullivan
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-11-14
Filing date: 1939-11-14
Publication date: 1942-09-01
Anticipated expiration: 1959-09-01

Description

F. c. SULLIVAN 2,224,582

PAVING 'BLOCK Sept. 1, 1942.

s vsheets-sheet 1 Filed NOV. 14, 1959 Fran cz's C. SuZZzvan Sept. 1, 1942.

F. c. SULLIVAN PAVING BLOCK 3 Sheets-Sheet 2 Filed Nov. 14, 1939 v-| lNvENToR Francis CSuZZL'Vm Patented Sept. 1, 1942 UNITED STATES TENT OFFICE 4 Claims.

This invention `relates -to a paving block and gparticularly `to :a block :adapted for the A,construction .of railway-crossings Various forms `of .railway crossings have :been

,proposed heretofore .but all -of them with which =I Lam familiar are* characterized .by serious deiects. Timber floored crossings, `for example, lack :the ldesiredduralfiilitin while Vother forms of construction w-h-ich yhave longer lfif-e .are undesirable :for ione reason or another. I have .invented a novel form ,of paving block :particularly suited for the zconstruction :of railroad crossings which entirely overcomes the objections to the cross- .ing ,floors -or paving .which have Abeen used Ahere- *.tofore.

In fthe preferred embodiment, kthe invention .comprises .fa .block having a ftread .portion of wearresisting :material such .as .cast `iron anda body portion of non-metallic .materia-l -such .as concrete. The tread and `body portions of the block Aare .secured together by .anchor vmembers embedded therein. The .blocks are of such dimensions `that they may be .easily laid side by iside .between the rai-ls -and on the outside of `the latter to form a ylevel pavement .presenting .a surface which is highly resistant .to abrasion. ,Numerous aother novel features and advantages `of `the invention will be pointed out 'during the course of the following detaileddescription which .refers to the `accompanying drawings illustrating `the preferred embodiment.

In the drawings- Fig. 1 :is a view partl-yin plan land 4partly in :section -on a Yplane parallel to the .tread surface;

Fig. '2 is -a Vlongitudinal section through a block, #taken :along the line I-I--I-I of Fig. 1 showing the vbloclr as installed at a crossing; vline I-I of 2 illustrates the Iplane of the -section shown 'in Fig. 1';

Fig. 3 is a transverse section through a railroad track having the blocks of my invention Vlaid I-thereon :to form alcrossing;

Fig. -4 isa transverse section through la block taken along the line LIV-IV of Fig. 2;

Fig. '5 is 'a similar section taken Ialong the Aline V`V `of Figa:

Fig. 6 is a partial kbottom jplan Aview of ,the tread portion;

Fig. 7 is .a .partial section taken along the line VII-VII of Fig. 6;

Fig. 8 yis 'a partial section through `the tread portion before the formation of the body portion, :showing an anchor member in an intermediate rvstage; fand Fig, 9 is a section showing a portion of Fig. 4 to enlarged scale.

Referring now in detail to the drawings, a paving block indicated generally lat I0 comprises a tread portion II an'd a body portion I2. The tread portion is preferably of abrasionresisting material such as cast iron and has its exposed surface roughened as by the formation of diamonds to provide good traction. The under-surface of the tread portion II is lnot flat but is grocved longitudinally and transversely as at I3 or otherwise shaped to provide preferred lines of fracture, for a, purpose which will appear later. A Vperipheral skirt or apron I4 ,extends .downwardly from the edge of the Vtread portion.

This skirt or apron tapers inwardly toward the exposed surface .of the tread portion. The tread has a longitudinal, .depending rib Ida.

The tread portion .I I may conveniently be cast in a .sand mold. Anchor members or struts I5 preferably in the form of double, twisted lengths of wire .are embedded in the tread portion when the latter is cast. The grooves I3 Yprovide a plurality of pyramidal projections I6 .on the under-face of the tread portion and, as shown in Fig. 6, one of the members I5 is disposed centrally of each pyramidal projection. As shown in the drawings, the eyes at the doubled ends of the anchor .members are embedded in the tread portion. vThe pattern .for .the tread portion may conveniently be slotted to receive the anchor members during the ramming of the mold. When the mold is completed andthe pattern removed, the anchor members are .supported with their eyes exposed in the mold cavity whereby they are embedded in the finished casting.

As shown in Figs. 8 and 9, the eyes in the anchor members I5 are large 4enough to permit the molten metal to flow therethrough, thereby forming a complete linkage which resists separation of the casting and the anchor member, Even in the absence of such complete linkage, however, the tapering outline of the eye resists such separation.

The wire from which the anchor members I5 are formed is of such size that there is practically no fusion, burning, nor crystallization thereof, by the heat of the molten iron during Ithe casting of the tread portion. As a matter of fact, the anchor members have the eiect of :chilling the cast iron immediately adjacent thereto, thereby providing the latter` with a close-grained surface and insuring a tight fit between the tread portion and the anchor members so that the latter are rigidly supported in proper relation during subsequent manufacturing operations.

Elongated holes I 'I are formed in the tread portion Il near each end thereof adapted to receive suitable lifting tools. Necks I8' depending below the tread portion around the holes il have notches I9 formed therein at right angles to the longer dimension of the holes I'I. The notches I9 are adapted to be engaged by the T-head of a lifting tool 29 when inserted through the holes I'I and turned 90.

When the tread portion has been cast with the eyes of the anchor members I embedded therein, the ends of the latter are twisted by any suitable means to form a shank 2|, the eX- treme ends being left open as at 22 to provide a chair for supporting reinforcing bars 23 adapted to be embedded in the body portion I2. The bars 23 are laid in the chairs and the open ends of the latter bent around the bars as shown in Fig. 9 and hammered down. The assembled tread portion, anchor members and reinforcing bars thus constitute a rigid assembly. The latter is deposited in a suitable mold with the tread portion Il down and concrete or the like is poured in the mold to form the body portion I2.

The struts I5 are spaced apart along the bars 23 by a distance less than the length of the struts and form a grid between the bars and tread portion which, with the concrete between the struts, constitutes a truss resisting any bending stress applied to the tread portion.

After the concrete has been poured into the mold, bearing plates 24 are embedded in each end of the block. The plates are preferably of cast iron, are L-shaped in section, and extend the full Width of the blocks. They are provided with integral chairs 25 forming seats for engaging the reinforcing bars. The inner horizontal surface of the plates may have pyramidal projections thereon, similar to those on the under surface of the tread plate, and may also have embedded therein wire anchors similar to those shown at l5, and secured to the reinforcing bars.

Holes 26 in alinement with the holes I'I are formed in the body portion by suitable cores. The sides of the body portion taper inwardly toward the bottom. The concrete of which the body portion is formed makes a tight bond with the under-surface of the tread portion, the bearing plates, the anchor members I5 and the bars 23 so that, to all intents and purposes, the resulting block is a unitary member.

The blocks Ill preferably have a length equal to twice the standard center-to-center spacing of railroad ties and a width such that three of the blocks disposed side by side fill up the desired portion of the space between the rails as shown in Fig. 3. The depth of the blocks as also shown in Fig. 3, is approximately equal to the height of the rail above the fiange thereof.

In constructing a crossing floor or pavement, the blocks I@ are laid longitudinally on the track with their ends resting on spacers 27 placed on the ties or sleepers. Wooden spacers 28 and 2S are disposed on each side of the rails indicated at 3d. The blocks are quite heavy, e. g., approximately 590 lbs., to prevent bouncing under the.

action of car wheels traversing the track. The blocks may be conveniently handled nevertheless by four men using two of the lifting tools 29. When properly placed, the blocks do not require any attachment to the track or ties, remaining in proper position thereon merely by virtue of their own weight. In laying the blocks on the ties, the end joints need not be staggered.

The upward taper of the skirt III provides grooves between adjacent blocks which may be filled with sealing material 3l to prevent seepage of water through the joints. The downward taper on the body portion I2 facilitates the removal of any block, if desirable for any purpose, as Well as the original setting of the blocks on the ties.

The plates 24 as shown in Fig. 2, bear on the spacer blocks 2l resting on alternate ties, and provide durable support-engaging surfaces.

' The block of my invention is characterized by numerous advantages over anything known heretofore. In the first place, the blocks are provided with an all-metal tread surface having a uniformly high resistance to abrasion. The blocks are unitary, for all practical purposes. Because of the rm anchorage of the members I5 in the tread portion Il and their attachment to the reinforcing bars 23, the body and tread portions are firmly bound together. Since one of the members I5 is embedded in each of the projections I6, breakage of the tread portion along the lines of grooves I3 would not permit the chipping out of fragments of the tread portion. Any breakage would follow the lines of the grooves I3 and even if cracks appeared along all such grooves, each separate fragment of the tread portion would be securely anchored to the body portion. The holes I1 and 26 permit circulation of air through the ballast in which the ties are laid to assist in drying it out. They also provide air vents during the vibration of the entire track under the car Wheels, thereby preventing the sucking-up of soil particles through the crevices between the ballast rock, and the resulting obstruction to drainage of the latter, as has been experienced with plastic materials laid in a continuous layer to provide a crossing floor or pavement. The blocks can easily be designed to have the desired strength when loaded as a beam supported at the ends of the span between alternate ties and may also be designed to have the weight necessary to hold it in proper position. The blocks are of such character, furthermore, that they may be manufactured at relatively low cost. They are practically indestructible under ordinary conditions and their durability, therefore, is almost unlimited. Since each block rests on only two ties, it is not necessary that the three ties covered by the length of each block be accurately leveled.

Although I have illustrated and described but a preferred embodiment of the invention, it Will be recognized that changes in the details of the construction disclosed may be made without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. A paving block comprising a metal tread portion and a non-metallic body portion, the lower surface of the tread portion having a multiplicity of pyramidal projections, and an anchor embedded in each pyramidal projection and eX- tending downwardly into the body portion, whereby any fracture of the tread Will follow the grooves between pyramidal sections, leaving all fragments firmly secured to the body porion.

2. A block adapted for use in railroad crossings or the like, comprising a cast metal tread portion and a non-metallic body portion, the top of the tread portion being roughened to provide good traction and the bottom of said tread portion having projections which together define intersecting grooves to provide preferred lines of fracture, reinforcing bars embedded in said body portion, and ties each having one end embedded in one of said projections and the other end secured to one of said bars.

3. A paving block adapted for use in railroad crossings or the like, comprising a cast metal tread portion, a non-metallic, reinforced body portion, Wire struts having one end embedded in said tread portion and the other end secured to the reinforcement in said body portion, the bottom of the tread portion having a plurality of lpyramidal projections, the sides of the bases of adjacent projections being alined and close together, said struts extending into the tread portion substantially through the apices of said projections.

4. A paving block particularly adapted for use on railroad crossings comprising a non-metallic body portion adapted to be supported on sleepers or the like, and a metallic tread portion bonded to said body portion, said body portion having horizontal metal reinforcing bars embedded therein adjacent the bottom thereof, and a plurality of struts also embedded in said body portion, said struts extending vertically between the bars and tread portion, secured to the bars and embedded in the tread portion, and spaced apart along the bars by a distance not greater than their length, thereby forming a grid connecting the tread portion to said bars and constituting, with the `material of the body portion therebetween, a truss resisting bending stress applied to said tread portion.

FRANCIS CL SULLIVAN.