US3735595A

US3735595A - Reinforced soil bridge

Info

Publication number: US3735595A
Application number: US00193727A
Authority: US
Inventors: R Watkins
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1971-10-29
Filing date: 1971-10-29
Publication date: 1973-05-29
Anticipated expiration: 1990-05-29

Abstract

The structure of the invention is particularly useful in building reinforced soil arch bridges having relatively long transverse axial spans in the range of 30 feet or more. Structure includes a substantially cylindrical liner of relatively thin wall corrugated metal sheet. The structure is characterized by the provision of one or more open-top bins disposed along the upper surface of the liner. Earth-fill is compacted in layers in the bins and around the liner. The bins serve to confine and thus reinforce and strengthen the compacted earth-fill so that a reinforced soil bridge is formed. The bins also serve as stiffeners for the liner.

Description

United StatesPatent [191 [111 3,73,59 Watkins 5] May 29, 1973 REINFORCED SOIL BRIDGE [75] Inventor: Reynold K. Watkins, Logan,.Utah Primary 'f f williamowsky Assistant Exammer-Phil1p C. Kannan [73] Asslgnee: United States Steel Corporation, An0rney DOna1d S Ferito Pittsburgh, Pa.

221 Filed: Oct. 29, 1971 [571 ABSTRACT [21] APPL No; 193,727 The structure of the invention is particularly useful in bulldlng relnforced SOll arch brldges having relatively long transverse axial spans in the range of 30 feet or [52] US. Cl ..6l/16 more Structure includes a substantially Cylindrical 51 Int. cl ..F16l9/04 liner of relatively thin wan corrugated metal sheet [58] Field of Search ..61/l6, 39, 15 14, The Structure i characterized by the provision of one 61/10 35; 94/33 or more open-top bins disposed along the upper sur face of the liner. Earth-fill is compacted in layers in [56] References c'ied the bins and around the liner. The bins serve to con- UNITED STATES PATENTS fine and thus reinforce and strengthen the compacted Y Y Y earth-fill so that a relnforced soll bridge is formed. 3,508,406 4/1970 Fishers". ..61 16 The bins also serve as stiffeners for the liner.

701,034 5/1902 Gray 4/]935 Carswell et al. ..6l/l6 7 Claims, 4 Drawing Figures REINFORCED SOIL BRIDGE BACKGROUND OF THE INVENTION As is well known, corrugated culvert construction results in an arch-type bridge comprising two individually weak elements, a relativelythin galvanizedcorrugated steel liner, and an archof compacted soil over the liner. Although the liner and the arch'of compacted soil are each individually weak, the combination of the two I as the amount of steel used in the construction increases or if anexcessive amount of concrete is needed to provide abutments or buttresses. The thickness of the steel liner is, therefore, an important consideration and must be held to a minimum commensurate with the length of span and depth of soil cover. Prior to my invention these considerations for the most part limited the structure of culvert bridges to those having a length of transverse axial span less than 30 feet. Certain types of structures have been suggested for providing long span culvert bridges; however, none of these have been entirely satisfactory for economic or other reasons. One such type of culvert construction is taught by U.S. Pat. No. 3,508,406. Other U.S. Pats. relating to archtype bridge construction are the following: Nos. 597,590 to Pratt, 1,926,843 to Fischer, 1,964,313 to Carswell et al., 1,999,500 to Carswell et al., 2,056,349 to Evers, 2,126,091 to Claybaugh, 2,126,870 to Carswell et al., 2,536,759 to Martin et al., 2,718,117 to Boyle et al., 3,282,056 to Fisher, and 3,495,410 to Bailey et al.

It is, accordingly, the primary object of my invention to provide an improved reinforced soil arch bridge construction which is economical and makes possible the construction of reinforced soil bridges having longer transverse axial spans than was heretofore possible.

It is a more specific object of my invention to provide a reinforced soil bridge structure of the type set forth in the object stated above which includes a relatively thin wall substantially cylindrical metal liner and one or more open-top bins which are disposed along the length of the upper surface of the liner. Well compacted earth-fill consisting of sand and/or gravel surrounds the liner and fills the bins.

These and other objects will become more apparent after referring to the following specification and attached drawing, in which:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a substantially schematic view in perspective and partly in section showing a preferred embodiment of my invention;

1 FIG. 2 is similar to FIG. 1 but showing a modified embodiment of my invention;

FIG. 3 is similar to FIG. 1 but showing still another modified embodiment of my invention; and

FIG. 4 is similar to FIG. 1 but showing yet another modified embodiment of my invention.

DESCRIPTION OF TI-IEPREFERRED EMBODIMENTS Referring more particularly for the time being to FIG. 1 of the drawing, reference numeral 2 designates the liner of the bridge of the invention. The liner is comprised of a number of heavy gage sheets or thin plates "(approximately 0.1084 to 0.50 inches thick) bolted together at overlapping points (not shown) into substantially cylindrical shape. The individual sheets or plates are shop-fabricated, i.e., corrugated, shaped and galvanized in the shop, and then subsequently assembled into the substantially cylindrical shaped'liner at the site. The assembled liner serves as a form for earthfill 4, which is preferably sand and/or gravel, placed in layers on both sides of the liner with the individual layers being tightly compacted by rolling, vibrating, or other suitable means. The progressive compacting of soil against the liner 2 stiffens the latter.

Fin elements 6, which may be steel sheets or plates, or other suitable material, corrugated or flat, are provided attached to, by welding or other means, projecting from the exterior of the liner 2-extending longitudinally thereof. The fin, element 6 may project from the exterior of the liner 2 at any angle, as desired.

A plurality of substantially triangular shaped plates 8 are spaced along the length of each of the fin elements 6 with each plate being disposed with its 'base attached upright and edgewise to the inner surface of its respective fin element 6. Each plate 8 is attached to the exterior of the liner 2. The plates 8 may be attached to the fins 6 and to the exterior of the liner 2 by welding or other suitable means. The triangular plates 8 attached to one fin element 6 extend toward the opposite fin element. The plates act to stiffen-the liner 2 and together with the fin elements 6 form bins 10. The bins 10 are filled with the compacted earth-fill 4. The bins 10 confine the soil over the liner thereby increasing the soils shearing strength such that wedges or'slices thereof cannot slip down.

If desired, the fin element 6 may be discontinuous, as shown in FIG. 2. For purposes of obtaining positive drainage, the fin element 6 may be disposed, detached from and not abutting the liner 2 as shown in FIG. 3. In this arrangement the triangular plates 8 are attached to the outer surface of the liner.

FIG. 4 shows an embodiment of the invention wherein only one bin 10 is provided on the liner 2. This arrangement has particular utilization in the construction of relatively narrow soil bridges, such as pedestrian crossovers.

In each of the embodiments shown in FIGS. 1, 2, 3 and 4, the opposing triangular plates 8 may be joined at their apices to form continuous elements extendin from one fin to the opposite fin.

If desired, the assemblies consisting of the bins 10, the triangular shaped plates 8 and the fin elements 6 may be positioned loosely on the liner while the earthfill is compacted therein and therearound.

It will be noted that although I have shown the liner 2 as a substantially continuous cylinder, it may be another cylindrical form, such as an arch supported on footings.

It will be obvious that the arrangement of my invention provides a reinforced soil bridge wherein the soils shearing strength is increased to an'amount not possible heretofore so that wedges or slices thereof cannot slip down and weaken the soil bridge.

While I have shown but four embodiments of my invention, other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. A reinforced soil arch bridge comprising a metal liner having an upper portion, an open-top bin on said liner, said bin having opposed side and end walls projecting upwardly of said liner to a substantially common horizontal plane above the upper portion of said liner, and compacted earth-fill contained in said bin and surrounding said liner.

2. A reinforced soil arch bridge comprising a metal liner having an upper portion, a plurality of open-top bins disposed along said liner, each of said open-top bins having opposed side and end walls projecting upwardly of said liner to a substantially common horizontal plane above the upper portion of said liner, and compacted earth-fill contained in said bins and sur rounding said liner.

3. A bridge as defined by claim 2 in which said bins are spaced apart along said liner.

4. A reinforced soil arch bridge comprising a longitudinally elongated metal liner, a plurality of open-top bins spaced longitudinally along said liner, said plurality of bins being formed of a pair of spaced fin elements projecting from but not abutting or attached to the exterior of said liner, a plurality of substantially triangular shaped plates spaced along the length of each of said fin elements, each of said triangular plates being disposed with its base attached upright and edgewise to the inner surface of its respective fin element and one edge thereof conforming with and attached to the exterior of said liner, the triangular plates attached to one fin element extending toward the triangular plates attached to the other of said fin elements, and compacted earth-fill contained in said bins and surrounding said liner.

5. A bridge as defined by claim 4 in which said fin elements are in abutment with and attached to the exterior of said liner.

6. A bridge as defined by claim 4 in which said fin elements are discontinuous forming separate sections and a pair of spaced triangular plates is attached to each of said fin element sections thereby forming spaced apart bins along said liner.

7. A bridge as defined by claim 6 in which said fin elements are in abutment with and attached to the exterior of said liner.

Claims

2. A reinforced soil arch bridge comprising a metal liner having an upper portion, a plurality of open-top bins disposed along said liner, each of said open-top bins having opposed side and end walls projecting upwardly of said liner to a substantially common horizontal plane above the upper portion of said liner, and compacted earth-fill contained in said bins and surrounding said liner.