ES2356964B1 - ARTIFICIAL BASKET FOR RAILWAY INFRASTRUCTURES. - Google Patents

Abstract

Artificial ballast for railway infrastructures. # The invention consists of artificial particles designed for use as a ballast in railway infrastructures in substitution of the crushed natural rock particles that currently compose it. # The particles that form the artificial ballast are synthetic elements with a high degree of control in two fundamental characteristics: geometry (shape and dimension) and material composition. Various shapes (polyhedral, frustoconical, ellipsoidal, spherical), different dimensions and different materials have been determined, which combine to form a synthetic granular material whose controlled properties, performance and behavior perfect those of the naturally occurring ballast. # The artificial ballast allows , with respect to the natural ballast, improve the mechanical behavior and increase the life of the ballast bed, as well as reduce the maintenance costs of the track and reduce the environmental impact generated by the exploitation of natural rock quarries.

Description

Artificial ballast for railway infrastructure.

Object of the invention

The present invention relates to a system of modular arti fi cial elements whose material geometry and composition are designed in order to produce a rail ballast of controlled characteristics and improved performance with respect to the ballast of natural origin currently used. Background of the invention

The ballast track is a typology of railway infrastructure backed by practice and with continuous and recent application on railway lines with the highest demands, such as high speed.

The advantages of the ballast track solution are multiple, highlighting the construction economy and the adaptability of this typology to correct the geometric track defects that appear throughout its useful life. In addition, the fl exibility of the ballast layer and its damping capacity make the ballast the most appropriate typology for the reduction of noise and vibrations produced by rail traffic.

However, the ballast track solution has disadvantages that can be summed up in the need for relatively frequent track geometry maintenance operations, in a relatively short lifespan of this material (between 15 and 30 years, depending on the traffic), and problems associated with ballast flight in the case of high-speed traffic.

A good part of the disadvantages of the natural ballast derive from the ignorance of their behavior, since since it is a material coming from the crushing of natural rocks of metamorphic type, neither the geometry, nor the characteristics of the material can be precisely defined, if not within of intervals, within which, these have a random character.

On the other hand, the use of this material represents an increasing cost and environmental impact, due to the need to find rock quarries that provide a natural ballast that meets the increasingly severe demands of current regulations.

The improvements introduced gradually in the elements that make up a railway infrastructure have come down. In the case of the rails, with the improvement of the alloys and the treatment of the steel, in the case of the devices that fix the rail to the crossbar, with the improvement of the design and of the metallic and polymeric materials, in the case of the sleepers, with the replacement of the traditional wooden sleepers with first reinforced concrete sleepers and currently prestressed concrete.

Within the tendencies of improvement of the railway infrastructure, the substitution of the ballast road is currently being proposed by the solution called the plate track, generally of reinforced or prestressed concrete.

The plate track solution involves moving from a natural material to another designed (concrete slab) and therefore giving up the advantages of the ballast, raising important technical questions (requirement of a perfectly executed and stable slab support in a very long term , difficulty in corrective maintenance of track or repair, demand for more expensive, complex and difficult to maintain rail fasteners, loss of track flexibility, increased noise and vibration).

Artificial ballast therefore represents an alternative solution, and to some extent intermediate, between the natural ballast track and the plate track, incorporating the qualities of the ballast (granular medium) and those of the plate track (design and controlled materials) . This dynamic of improvement leads to considering the ballast from the point of view of the design of the particles (geometry) and from the point of view of the design of materials (composition), obtaining a material controlled in its nature and in its production.

The use of arti fi cial modules of specific geometries is well known especially in general works of maritime and river protection, as well as for military defenses and traffic on track. As an example, those described in Patents ES 2 224 874 and WO 95/32338, or concrete modules of the Tetrapode ™, Accropode ™ and Core-Loc ™ type.

On the other hand, there are numerous antecedents in the production of design aggregates for concrete purposes (for example, ARLITA® for light fillings or for the production of lightened mortars) and to replace natural materials with artificial materials in structures, enclosures or coatings in buildings.

There are also methods of strengthening and consolidating a natural ballast by adding polymeric modules with elastic characteristics (Patent FR 2202978 A1-Shimizu) or by injection of polyurethane foam (US Patent 20070172590-Hoffmann). These improvements, while increasing the efficiency of natural ballast, essentially solve a small part of the problems posed, which the artificial ballast is intended to solve as a whole. Description of the invention

Artificial ballast is composed of a plurality of synthetic particles of selected geometry (shape and dimension) and material composition, manufactured by an industrial process.

The regulatory requirements for the supply of railway natural ballast (mainly, and at the national level, the “ORDER FOM / 1269/2006, of April 17, Chapter 6.-Ballast, of the General Technical Specifications for Rail Materials”) represent the basic starting criteria that allow to determine the appropriate material geometry and composition of the artificial ballast.

As for the geometry, on the one hand, the shape of the particles of the artificial ballast can be polyhedral, truncated, ellipsoidal or spherical, or a mixture of these, with indentations oriented to increase the frictional forces between particles. On the other hand, the particles have different dimensions (understood by dimension the radius of the sphere in which a particle would be inscribed) reasonably consistent with the granulometric spindle defined in the aforementioned ORDER FOM / 1269/2006.

As for the constituent material of the elements of the artificial ballast, it consists of concrete or mortar made with small aggregate aggregate and with a hydraulic type binder material (high performance cements) or mixture of hydraulic binder with bituminous binder, with optional addition of fly ash and / or synthetic fibers.

The possible combinations of geometries and materials will respond to the specific railway application (different types of railway lines) or to specific characteristics desired or the degree of improvement desired in terms of performance.

The artificial ballast will reduce the maintenance costs of the geometry of the track given its greater stability, as well as optimize the performance of the machinery currently developed for the extension, stabilization and batting of the natural ballast, machinery that would be usable with few adaptations

or improvements.

Another important advantage of the artificial ballast is that it constitutes an improvement that can be introduced in lines already built without significant reduction of the rail traffic, through its gradual introduction and with absolute flexibility in the railway network in service.

Furthermore, the industrial scale production of the artificial ballast will entail the following advantages:

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the increase of its useful life with respect to the natural ballast, which may compensate for its higher cost;

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the production price will be a relatively stable cost, as is the cost of prefabricated elements in civil works;

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the implementation of production units at strategic points (linked to the rail transport network) or of smaller production plants on site, will be economic efficiency factors due to reduced transport costs;

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being a prefabricated one, the cost will be adjusted by the natural competition currently altered in the case of the artificial ballast by the limited number of quarries;

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Being a designed product, its production can be adapted to the requirements of the infrastructure (conventional line, high speed, commuter lines) or to specific requirements of noise reduction and mainly vibrations by rail traffic (lines in urban environment).

On the other hand, the artificial ballast will minimize the environmental impact since:

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it allows to avoid the opening of new rock quarries of significant environmental impact;

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It is based on the production of concrete or mortar with cement-type binder or mixture of cement and bituminous materials, which allows synergies with the efforts of the cement or petroleum industry to achieve less polluting production;

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it may allow the use of waste or materials from recycling processes (fly ash, slag, tire dust);

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as in the case of the natural ballast, it is reusable as coarse aggregate (concrete, gravel, encachados);

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by prolonging its useful life, it means saving material over time;

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when manufactured in rationally located plants, the contaminating effect of material transport can be reduced or more environmentally friendly transport such as rail can be used.

Claims (3)

1. Artificial ballast for railway infrastructures, consisting of a plurality of synthesized particles, characterized by their ellipsoidal, spherical, truncated conical or polyhedral shape, or by a mixture of these, with indentations to increase friction between particles; by its dimensions in proportions determined by a granulometric spindle that limits the dimensions of the particles between 25 mm and 100 mm; for its constituent material composed of concrete or mortar with small aggregate aggregate and hydraulic binder (high performance cement) or compound of concrete or mortar with aggregate of small size and binder mixture of high performance cement and bituminous product or consisting of a mixture of both compounds, said particles being made by an industrial prefabrication process. 2. Artificial ballast for railway infrastructures, according to claim 1, characterized in that the constituent material of the particles that make up the ballast includes the addition of fly ash and / or synthetic fibers. SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 200800353 SPAIN Date of submission of the application: 11.02.2008 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: E01B1 / 00 (2006.01) RELEVANT DOCUMENTS

Category

Documents cited Claims Affected

TO

FR 2748044 A1 (SOGELERG SOGREAH) 31.10.1997, page 4, line 17 - page 5, line 15; figures. one

TO

JP 10331101 A (OHTSU TIRE & RUBBER CO LTD) 15.12.1998, Summary of the EPODOC database. Recovered from EPOQUE; figures. one

TO

GB 189911805 A (ROUSE THOMAS) 07.04.1900, the whole document. one

TO

CN 1919563 A (NAJING DONGDA SUWEI ENERGY SOU) 28.02.2007, Summary of the EPODOC database. Recovered from EPOQUE. one

TO

JP 2000169204 A (CHUDEN KANKYO TECHNOS KK) 20.06.2000, Summary of the WPI database. Recovered from EPOQUE. one

TO

US 2005118297 A1 (STEINBERG DOV) 02.06.2005, paragraphs [5-6,34-39]; Figures 1A, 1B. one

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims • for claims no:

Date of realization of the report 25.03.2011

Examiner J. Angoloti Benavides Page 1/4

REPORT OF THE STATE OF THE TECHNIQUE Application number: 200800353 Minimum documentation searched (classification system followed by classification symbols) E01B, E02B Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, EPODOC State of the Art Report Page 2/4  WRITTEN OPINION Application number: 200800353 Date of Completion of Written Opinion: 03.25.2011 Statement

Novelty (Art. 6.1 LP 11/1986)

Claims Claims 1-2 IF NOT

Inventive activity (Art. 8.1 LP11 / 1986)

Claims Claims 1-2 IF NOT

The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986).  Opinion Base. This opinion has been made on the basis of the patent application as published. State of the Art Report Page 3/4  WRITTEN OPINION Application number: 200800353 1. Documents considered. The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

FR 2748044 A1 (SOGELERG SOGREAH) 10/31/1997

D02

JP 10331101 A (OHTSU TIRE & RUBBER CO LTD) 15.12.1998

D03

GB 189911805 A (ROUSE THOMAS) 07.04.1900

2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement The invention relates to an artificial ballast for railway structures, formed by a plurality of prefabricated particles, by concrete or mortar, spherical, conical, ellipsoidal, polyhedral or a combination. The particles are indented outside. The particles have a granulometric spindle between 25 and 100mm. In the dependent claim additives are added to the mortar or concrete. It is known in the state of the art the use of artificial stones formed for the realization of concrete ballast in hydraulic works. D01 offers an example in which the ballast is polyhedral in shape and has a roughness to increase friction between elements. This ballast is not directly applicable to railway structures, since it is carried out on a very different scale, totally outside the range defined in the claim. It is not specified whether the concrete meets the composition conditions set forth in the independent claim, although it results in a composition known in the state of the art. From D02, elements of railway ballast with spherical shape (figures 2.5), conical trunk (figure 3), polyhedral (figure 8.9) or the like are known. These elements are not made of concrete but of elastomers and mixed with natural ballast. D03 discloses a method of manufacturing building stones that comprises concrete with fine aggregates and that is molded to give it the final shape. No examples of resulting forms are given. No document, or obvious combination of documents, that sufficiently anticipates each and every one of the characteristics of the independent claim has been found. Therefore, the two claims of the application would have novelty and inventive activity according to articles 6 and 8 of Patent Law 11/1986. State of the Art Report Page 4/4