US1888287A - Ferro-concrete railway sleeper - Google Patents

Description

Nov. 22, 1932. -r 7 1,888,287

FERRO-CONGRETE RAILWAY SLEEPER Filed Aug. 15, 1929 3 Sheets-Sheet 1 Nov; 22, 1932. E. M. PROT FERRO-CONCRETE RAILWAY SLEEPER Filed Aug. 15, 1929 3 Sheets-Sheet 2 Z 721 FMZL Nov. 22, 1932.

E. M- PROT FERRO--CONCREITE RAILWAY SLEEPER Filed Aug. -15, 1929 3 Sheets-Sheet 3 S. 777, pM'

Patented Nov. 22, 1932 UNITED STATES PATENT OFFICE ETIENNE MAROEL rRoT, or PARIS, FRANCE, ASSIGNQR ro soorE'rE A REsroNsA ILr'rE LIMITEE BITE: LA voIE EERBE' MODERNE, or PARIS, FRANCE FERRO-CONCRETE RAILWAY SLEEPER Application filed August 15, 1929, Serial No. 385,996, and in France March 1, 1929.

For replacing wooden sleepers on rail ways, use has already been made of ferroconcrete sleepers and, through habit, these latter have usually been made in the shape of a parallels-piped as the first ones, so that the materials are not used in a rational manner.

On the other hand, the shape given to wooden sleepers and; which was the consequence of the very nature of the material, of

its origin and of its working conditions, it it answered to the rational transmission of vertical stresses (provided use was made of a layer of ballast) answered rather badly to the condition of resistance to horizontal stresses to which the track is subjected.

By giving to ferro-concrete sleepers a shape similar to that of wooden sleepers, inconveniences inherent to these sleepers are met with, to which is added that due to the very slight flexibility of ferro-concrete under the unequal loads to which it is subjected, to

such an extent that it has been necessary, in certain existing ferro-concrete sleepers, to provide special devices for increasing this flexibility.

The present invention has for object a new type of ferro-concrete railway and tramway sleepers characterized by a high and recessed shape and a wide sole portion so as to obtain a suitable distribution of the loads, a small unitary pressure on the ground and a rational use of the materials.

The invention also consists in the following detail objects constituent of the inain object:

(a) The hollow vertical web of the sleepers terminates in divergent ribs absorbing the horizontal stresses, the sleepers being embedded in the ground. The horizontal 40 stresses are also transmitted to the ground by the ribs of the inner face.

(6) The rails rest on the sleepers with interposition of a thick shock-absorbing wooden sole portion held in the sleeper and are secured on the latter by clips and bolts clampedon the sleeper by means ofresilient plates constituting unloosening devices.

('0)- The sleepers are recessed or hollowed out throughout their length or on one or more 150 portions of the latter.

The accompanying drawings illustrate, by way of example, a, form of construction of the improved ferro-concrete sleeper iiraccordance with the present invention.

Figure 1 is an elevation of this sleeper.

Figure 2 is a longitudinal section thereof.

Figure 3 is a plan. view of the same.

Figure 4 is a section made according to line IVIV of Fig. 1.

Figure 5 is a section made transversely to a track constructed with sleepers similar to that shown, in Figs. 1 we.

Figure 6 is a section made longitudinally to the said track.

Figure 7 is a longitudinal section, on an; enlarged scale, or the sleeper, showing how the rails are arranged on the sleeper.

Figures 8 and9 are respectively an elevation and a plan view of a modification: of this form of construction.

Figure 10is a sectional elevation of a modi fication comprising an arrangement allowing to secure in position double headed rails.

Figure 11 is a longitudinal section of a track equipped with suchsleepers.

Referring to Figs. 1 to 7 the sleeper is constituted, in accordance with the invention, by awide sole portion 1 having an upward extension formed by a recessed web 2, the side faces 3 of which terminate in divergent ribs 4.

At the ends of the sole portion, the edges of thelatter terminate in a shape ensuring an equal resistance, as illustrated in Fig. 3, so. as to cause the materials constituting the sleeper to work in the best conditions.

The shapeot the sleeper allows. to obtain,

under a reasonable weight, a resistance to vertical stresses so much the more great as the surfaceof the sole portion 1 is greater, and a resistance to side stresses also very satisfactory, owing to the fact that the sleeper is embedded in the ground, as shown in Figs. 5

and 6, and that the divergence of the ribs 4 prevents any side displacement of the sleeper. The ribs 410 and lb of the lower face contribute to transmit to the ground the horizontal stresses, which are themselves transmitted to the sleeper through the rail.

The depth of the web 2 gives to the sleeper a great moment of inertia.

: cesses 11 pass bolts The recessed portion 6 of the web 2 allows to easily arrange the bolts 5 for securing the rails, and at the same time it reduces the weight of the sleeper (Fig. 7

The rails 8 respectively rest on a sole portion 7 made of a relatively resilient material (oak impregnated with creosote or the like), relatively thick and which is held in a mortice 9 provided in a bulged portion 10 which is formed on the sleeper opposite the passage of each rail.

Opposite the mortice 9, the web 2 is provided with side ribs 17 connected to the sole portion and to the web by curved portions and adapted to strengthen the said web at the place where the rails rest on the same.

In the axis of the sleeper, on either side of the mortice, are provided recesses 11 adjacent to the latter and in which are arranged clips 12 for holding the rail and the wedges made of oak impregnated with creosote, or any other resilient material 13 on which rest the clips 12.

Through the clips 12, wedges 13 and re- 5, the nuts 14: of which directly bear against the clips 12, and the heads 15 of which fit upon the upper inner face of the recessed web 2, with interposition of a resilient metal. plate 16.

This application of the bolt by both its faces on resilient members allows to obtain a firm clamping and a very rigid securing in position of the rails, thus avoiding any risk of unloosening and of spacing apart of the rails.

For preventing oxidation of the screw threads of the bolt extending above the nut and for the ease of removal, the nut can be a cap nut or a blind nut, or it can be covered with a pressed sheet-iron member covering the nut and the top of the bolt, with interposition of tar or of any other similar material.

It is to be noted that the recessed shape of the sleeper, which might be recessed only at its end portions, allows the easy placing in position and removal of the bolts, which can thus be readily replaced. The attaching member which is not integral with the concrete and is completely independent of the same, can easily be electrically insulated by simply coating with tar the metal parts and the concrete, or by interposition of any suitable insulating material.

The arrangement of thick resilient sole portions under the rails allows to obtain a very soft running.

The adjustment of the track, upon settling of the ground, can be effected by packing, this adjustment can moreover be eifected, to a certain extent, by simply replacing the sole portions by sole portions of greater thickness.

On the other hand, owing to the wide sole portion of the sleepers, which allow the satisfactory distribution of the vertical stresses and the transmission to the ground of a small unitary pressure, the use of ballast, can be dispensed with, the latter being, so to speak, incorporated, under a much more eflicient form, in the sleeper itself; the so-called tamping layer formed of choice materials, can at least be dispensed with and use ismade only of an under layer formed of sand or gravel, which is less costly.

In fact, the small pressure per square centimeter transmitted to the ground by the wide bearing surface prevents the ground from being permanently unlevelled; as the ground is only resiliently distorted, the sleeper does not get out of the ballast, resulting in a better anchoring of the track and a reduced cost of maintenance.

Besides, the track equipped with sleepers which are in accordance with the invention, embedded in the ground, has an extremely satisfactory appearance, it is easy to run over,

to inspect and to maintain in a perfect condition of cleanliness.

Figures 8 and 9 illustrate a modification of the first form of construction described, characterized in that the sleeper is narrower in its central portion.

This sleeper presents the same features and the same advantages as the preceding sleeper.

In Figs. 10 and 11, are shown wedges 23, made of wood or similar materials, opposite the screw spikes 21 of the chair 22.

The placing of the wedge and its replacement in case of need are effected with the greatest ease, through the recess, without necessitating the removal of the sleeper from the track. As in the attaching member made entirely of metal, a member is provided which presses the rail on the sleeper and is ulled downwardly (the screw spike), as we 1 as a member bearing on the underside of the sleeper and pulled upwardly. This latter member, the wooden wedge, constitutes at the same time the resilient member ensurin the permanence of the clamping. This attac ing member is cheaper than the attaching member made entirely of metal, and it can be used in its place and stead in any case; if it is considered as being not so safe and less perfect in the case of the Vignole rail, it is, on

the other hand, to be recommended for securing the rail-chairs, the screw spike being then ungble to incline as in the case of the footrai a It is to be noted that the wooden wedge, which is moreover previously coated with tar, is practically sheltered from the action of moisture and weather conditions.

Owing to its recess, this latter sleeper, as the preceding sleepers, can be very easily manipulated.

For loading and unloading it is easy to grasp it by means of two hooks fitting in the ends of the recess. For the placing in position and the adjustment, it is easy to manipulate it by inserting in the recess, at each end, a lever of suitable shape and dimension.

It is to be understood that the forms of construction described have been given by way of example only, and that the number, shape, 6 arrangement, nature and assemblage of the various parts can be modified in any suitable manner without departing from the scope of the invention.

What I claim as my invention and desire 14) to secure by Letters Patent is A ferro-conorete railway sleeper including a relatively wide sole portion, an upward extension continuing therefrom in the form of a hollow web, divergent ribs between the ends 15 of the web and the sole portion, reinforcing and anti-creeping ribs on the under surface of the sole portion, rail seats provided on the upper surface of the web near the opposite ends thereof, additional ribs on opposite sides of the web between the seats and sole portion for reinforcing purposes, and the sole portion and its extension having a depth at least equal to that of an ordinary timber sleeper increased by that of an ordinary layer of ballast and the sole portion having the value of at least double that of an ordinary timber sleeper.

In testimony whereof I have signed this specification. ETIENNE MAROEL PROT.

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