In this article we will talk about what these products are, as well as the features of their production and operation. Let's consider where used reinforced concrete sleepers are used, and what requirements are imposed on manufacturers of this type of material.

Initially, stone blocks were placed under the railway rails. A little later, stone was replaced with wood, which not only had better shock-absorbing qualities, but was also easier to machine. However, the situation changed dramatically only when the production of reinforced concrete sleepers began.

A little history

In the photo - wooden sleepers after long-term use

As already mentioned, the history of railways includes several types of supports that are placed under the rails. All solutions had a number of operational shortcomings. For example, the stone was extremely difficult to process and had low shock-absorbing properties.

In addition, despite their apparent strength, these slabs were not the most durable solution, since due to prolonged mechanical exposure they cracked and became partially or completely unusable.

The situation was slightly better with wood products. Such sleepers were tarred to protect against the negative effects of environmental factors. But wood, sooner or later, despite special treatment, rots. And, as a result, the railway tracks require repairs.

Despite the good shock-absorbing properties, wood has one significant drawback - the high price of lumber, even taking into account the ease of their mechanical processing. The situation changed for the better in the second half of the twentieth century when the first reinforced concrete sleepers were developed.

Despite the fact that wooden products are still used on secondary branches, it is reinforced concrete structures that are rightfully considered the most modern and promising solution.

Main characteristics

The instructions for using reinforced concrete sleepers in the post-Soviet space have been tested for more than 40 years.

In accordance with GOST 23009, modern concrete sleepers are rail supports made in the form of beams with variable size and cross-sectional shape. The product is reinforced with reinforcing wire with a cross-sectional diameter of 3-6 mm, depending on the modification.

During operation, the product is laid on top of the ballast layer. In relation to conventional tracks, large-sized crushed stone is used as a ballast embankment, and when arranging the subway, a slab-type concrete base is used.

Products made of prestressed reinforced concrete, used as under-rail supports, are the optimal solution for both continuous and other categories of tracks.

The relevance of these designs is explained by a number of technical and operational advantages, including:

• long service life;
• optimal indicators of resistance to the negative effects of environmental factors;
• non-susceptibility to rotting throughout the entire service life;
• Possibility of installation on tracks with any level of congestion;
• relatively low price;
• minimum costs required for operational maintenance;
• ease of installation and installation, in comparison with wooden analogues;
• absolute identity of standard sizes, shapes and weights, which guarantees ease of transportation and shipment.

In the photo - tongs for carrying sleepers

Are there any disadvantages that could negatively affect the use of these concrete products?

There are few such disadvantages:

• Firstly, there is the possibility of fatigue failure of the concrete structure and, as a consequence, the need for periodic inspection of the tracks.
• Secondly, the weight of the reinforced concrete sleeper (270 kg) makes it impossible to install it yourself without the use of special equipment. Therefore, unlike wooden analogues, concrete structures are installed using specialized sleeper layers.

Scope and conditions of application

Sleepers made using prestressed concrete are widely used in the construction of railway transport links around the world.

Considering the variety of climatic conditions in which these products are operated, as well as the varying degrees of mechanical loads, increased demands are placed on the production of sleepers, as well as on the quality of the finished product. As a result, depending on the favorable conditions of use, these reinforced concrete products can be used in for 30-60 years.

The widespread replacement of conventional wooden supports with reinforced concrete analogues is explained not only by strength and durability, but also by short production times.

For example, the production of ready-to-install concrete products requires only a few hours, which is very convenient when we are talking about the construction of a large branch and the constant supply of large volumes of building materials is required. Again, concrete products can be repaired and adapted for operational needs using diamond drilling of holes in concrete.

Important: Sleepers manufactured by domestic manufacturers using prestressed reinforced concrete in accordance with GOST requirements are superior to their foreign counterparts in terms of load-bearing capacity and material consumption.

Requirements for railway reinforced concrete sleepers

As already mentioned, the operating conditions in which sleepers are used place high demands on the production technology of these reinforced concrete products and, in particular, on the production technology of prestressed reinforced concrete.

The following requirements apply to the material and the finished product:

• Strength, sufficient to transfer the prestressing force within a few hours (the time is set in accordance with the modification of the reinforced concrete products) at the end of the production process.
• The highest possible degree of homogeneity of consistency freshly prepared concrete.
• Accuracy of sizes and shapes— an order of magnitude higher than similar requirements for other categories of commonly used reinforced concrete and prestressed reinforced concrete structures.
  These requirements mean tolerances on the angle of inclination, length and width of individual structural elements. The dimensions in areas adjacent to the rails are especially strictly controlled.

Important: In Western Europe, the technical requirements determining the quality of the starting material used in the manufacture of reinforced concrete sleepers are regulated by the EN 13230 standard.
The strength class of the source material in domestic production is determined by the higher requirements given in GOST 26633.

Manufacturing technologies

Regardless of whether the foundation is planned to be made of reinforced concrete sleepers or the reinforced concrete products will be used for their intended purpose, the strength of these structural elements will be guaranteed. The performance qualities of finished products are ensured by production technologies.

Despite the fact that many sleeper manufacturing methods have been tested over the course of more than fifty years, today the four most common production technologies that meet the requirements of international standards are widely used.

• Carousel technology with delayed mold removal.
  The peculiarity of this technological process is that the finished mixture is poured into molds and compacted. Removal of the product from the mold is carried out only after achieving optimal strength indicators sufficient to apply a prestressing force.
  During the manufacturing process, specialized collapsible cassette molds are used, which can accommodate up to six units of the product. Through the use of special tension mechanisms, pre-stressing of the reinforcing bars is ensured, which is subsequently transferred to the concrete and ensures optimal adhesion to it.
  Once the reinforced concrete sleeper is ready, the mold can be dismantled and immediately used for the next production cycle.
  The name of the method is explained by the type of production process and the design features of the molds used, which are located on a carousel-type transport system. This method has become widespread in Western European countries and is considered the most promising and technologically advanced.
• Linear technology.
  No matter whether the reinforced concrete half sleeper for rail cranes or a full-size product is manufactured, the production process can be realized based on linear technology.
  The production process uses a conveyor with a series of molds arranged in series. The total length of the chain is usually at least 100 meters.
  At the ends of the molds, special devices are used that not only close the mold, but also transfer pre-stress to the reinforcing bars. As the mixture dries, the force is transferred to the concrete.
• Technology of mold removal with subsequent tension.

In the photo - a modern line for the production of sleepers of Western European standard

In this case, templates are inserted into the forms, which will determine the location of the metal reinforcement. The concrete is then poured into the molds and compacted.

As it hardens, metal pins are inserted into the thickness of the mixture and applied mechanical force. After a short period of time, the mold is dismantled and the templates are removed. The advantage of this method is that the process is essentially continuous, and therefore a limited number of forms are needed to obtain the desired result.

• Technology of mold removal with pre-stressing.
  In this case, the form is removed as quickly as in the previous method. The only significant difference between this technological process is that the tensile force is transmitted to the product not through pins, but through frames.

Features of installation, repair and disposal of reinforced concrete sleepers

The photo shows the operation of a mobile sleeper

Laying railway tracks using reinforced concrete sleepers has a number of characteristic features.

Rails and concrete sleepers, during the construction of railways, are mounted on an initially prepared roadbed based on earth soil, sand and crushed stone backfill. In order to prevent damage to the sleepers during the passage of trains and ensure the safety of the roadbed, special preparation is required, which consists of installing sand strips .

Laying is carried out using mechanized systems that minimize the use of physical labor. As a result, the cost of the installation process is reduced, and in addition, the implementation time for laying the track as a whole is reduced.

As previously mentioned, the service life of reinforced concrete sleepers is limited to 30-60 years. But such durability parameters are only possible if the condition of the tracks is regularly inspected for breakages and partial deformations.

If the problem is not eliminated after the screw head comes off, in a relatively short period of time microcracks appear in the thickness of the concrete, which lead to partial or complete destruction of the sleeper.

The photo shows the work of a mechanized complex for recycling solid construction waste

At the end of their service life or due to natural destruction, sleepers must be replaced. At the same time, unusable concrete products must be disposed of.

Recycled sleepers can subsequently be used as materials for backfilling pits or for forming embankments.

Conclusion

Now you know how much a reinforced concrete sleeper weighs, how it is made and what its operational features are. We must assume that the use of these concrete products will be relevant and in demand for a long time.

Indeed, even despite the development of completely plastic sleepers in Japan, it is compliance with GOST for reinforced concrete sleepers that guarantees the optimal combination of strength, durability and reasonable cost. You can find more useful and interesting information by watching the video in this article.

GOST 10629-88

Group Zh83

INTERSTATE STANDARD

REINFORCED CONCRETE SLEEPERS, PRESTRESSED

FOR 1520 mm GAUGE RAILWAYS

Specifications

Prestressed reinforced concrete sleepers for 1520 mm gauge railways.

Specifications

MKS 91.080.40

OKP 58 6411

Date of introduction 1990-01-01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the USSR Ministry of Railways

2. APPROVED AND ENTERED INTO EFFECT by Resolution of the State Construction Committee of the USSR dated November 21, 1988 N 228

3. INSTEAD GOST 10629-78

4. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS

5. EDITION (July 2004) with Amendment (IUS 5-90)

This standard applies to reinforced concrete prestressed sleepers for railway tracks with a rail gauge of 1520 mm width and rails of types P75, P65 and P50, on which the standard rolling stock of the general railway network of the USSR operates.

1. TECHNICAL REQUIREMENTS

1.1. Sleepers should be manufactured in accordance with the requirements of this standard according to technological documentation approved in the prescribed manner.

1.2. Main parameters and dimensions

1.2.1. Depending on the type of rail fastening, sleepers are divided into:

Sh1 - for separate terminal-bolt rail fastening (KB type) with bolted attachment of the lining to the sleeper;

Ш2 - for inseparable terminal-bolt rail fastening (BPU type) with bolted attachment of the lining or rail to the sleeper.

1.2.2. The shape and dimensions of the sleepers must correspond to those indicated in Figures 1-4 and Table 1. Indicators of material consumption of sleepers are given in Appendix 1.

1 - embedded washer; 2 - wire reinforcement

Section 3-3 is shown in Fig. 3

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UNDER-RAIL PART OF SLEEP SH1-1

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UNDER-RAIL PART OF SLEEPER Ш1-2

Sections 4-4, 5-5 and 6-6 are shown in Fig. 2

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UNDER-RAIL PART OF SLEEP SH2-1

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Table 1

Notes:

1. On the edges adjacent to the sole and ends of the sleepers, chamfers with a width of no more than 15 mm are allowed.

2. By agreement between the manufacturer and the consumer, it is allowed to produce sleepers in which the dimensions and location of the recesses on the sole differ from those indicated in Figure 1, and the shape and dimensions of the vertical channels for embedded bolts differ from those indicated in Figures 2-4.

1.2.3. Sleepers are designated by marks in accordance with the requirements of GOST 23009. The sleeper mark consists of two alphanumeric groups separated by a dash.

The first group contains the designation of the type of sleeper (clause 1.2.1). In the second group, the design option for the under-rail platform is indicated (Table 1).

An example of a symbol (brand) of sleeper type Ш1, the first version of the under-rail platform:

Ш1-1

1.2.4. Depending on crack resistance, accuracy of geometric parameters, and quality of concrete surfaces, sleepers are divided into two grades: first and second.

Second grade sleepers are intended for laying on low-traffic, station and access roads. Second grade sleepers are supplied only with the consent of the consumer.

1.3. Characteristics

1.3.1. Sleepers must meet the crack resistance requirements adopted during their design and withstand the test loads specified in Table 2.

table 2

1.3.2. Sleepers should be made of heavy concrete in accordance with GOST 26633, compressive strength class B40.

1.3.3. The actual strength of concrete (at design age, transfer and tempering) must comply with the requirements of GOST 13015.

1.3.4. The normalized transfer strength of concrete should be taken equal to 32 MPa (326 kgf/cm ).

1.3.5. The tempering strength of concrete is taken to be equal to the transfer strength of concrete.

1.3.6. The frost resistance grade of concrete must be at least F200.

1.3.7. For concrete sleepers, crushed stone from natural stone or crushed stone from gravel of a fraction of 5-20 mm should be used in accordance with GOST 26633. It is allowed, by agreement between the manufacturer and the consumer, to use:

crushed stone of the 20-40 mm fraction in an amount of no more than 10% of the mass of crushed stone of the 5-20 mm fraction according to GOST 26633;

crushed stone from natural stone of fraction 5-25 mm in accordance with GOST 7392, subject to its compliance with all other requirements of GOST 26633.

1.3.8. As reinforcement for sleepers, periodic steel wire of class BP with a diameter of 3 mm should be used according to GOST 7348 and TU 14-4-1471.

1.3.9. The nominal number of reinforcing wires in a sleeper is 44. The location of the wires, controlled at the ends of the sleeper, must correspond to that indicated in Figure 5. The vertical clear distance between pairs or individual wires, in case of their deviation from the design position, should not be less than 8 mm. It is allowed to rotate pairs of wires by 90° while maintaining the above distance.

PLACEMENT OF FITTINGS

at the end of the sleeper

in the middle section of the sleeper

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To ensure the design arrangement of the wires, spacers that remain in the body of the sleeper concrete can be used (see Appendix 2). It is allowed, by agreement between the manufacturer and the consumer, to use spacers that differ from those specified in Appendix 2.

1.3.10. The total initial tension force of all reinforcing wires in the package must be at least 358 kN (36.4 tf). The average value of the initial tension force of one wire with their nominal number should be 8.12 kN (827 kgf). The tension force of individual wires should not differ from the average value by more than 10%.

A decrease in the tension force of individual wires in excess of 10%, caused by wire slipping in the gripper, should not occur for more than one wire in sleepers of the first grade and for two wires in sleepers of the second grade.

1.3.11. Deviations from the nominal number of reinforcing wires are allowed, provided that the total tension force of the existing wires is not less than that specified in clause 1.3.10. In this case, maximum deviations in the number of wires should not exceed ±2 pcs.

1.3.12. The ends of the prestressing reinforcement should not protrude beyond the end surfaces of the first grade sleepers by more than 15 mm and the second grade by more than 20 mm.

1.3.13. Embedded washers - according to the technical documentation.

1.3.14. The values ​​of actual deviations of the geometric parameters of sleepers should not exceed the limits specified in Table 3.

Table 3

Note. Dimensions for which maximum deviations are not indicated are for reference only.

1.3.15. The slope of the under-rail platforms to the longitudinal axis of the sleeper in a vertical plane passing through the axis (slope) should be in the range of 1:18 - 1:22 for sleepers of the first grade and 1:16 - 1:24 for sleepers of the second grade.

1.3.16. The difference in the slopes of the under-rail areas of different ends of the sleeper in the direction transverse to the sleeper axis (propeller ratio) should not exceed 1:80.

1.3.17. The values ​​of actual deviations in the thickness of the protective layer of concrete to the top row of reinforcement should not exceed, mm:

For sleepers of the first grade;

For sleepers of the second grade.

1.3.18. The dimensions of cavities on concrete surfaces and concrete edges of ribs near sleepers should not exceed the values ​​​​specified in Table 4.

Table 4

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* No more than three sinks on one platform.

**Limit one sink.

Notes:

1. It is allowed to have marks from welds between the permanent under-rail plates and the mold on the longitudinal edges of the under-rail pads.

2. The presence of imprints of diaphragm stiffening elements with a depth of no more than 5 mm at the ends of the sleepers is allowed.

1.3.19. The depth of the gaps between the wires and concrete at the ends of the sleepers should not exceed 15 mm for sleepers of the first class and 30 mm for sleepers of the second class.

1.3.20. The following are not allowed in sleepers:

sagging of concrete in the bolt channels, preventing the free installation and rotation of these bolts into their working position;

local flows of concrete on under-rail areas;

turning the rail fastening bolts in the sleeper channels while screwing the nuts;

cracks in concrete.

To form channels for bolts, it is allowed to install internal elements, the design and material of which are agreed upon with the consumer.

1.4. Marking

1.4.1. The marking of sleepers must comply with the requirements of GOST 13015 and this standard.

1.4.2. On the upper surface of the sleepers the following is applied by stamping during molding:

trademark or short name of the manufacturer - on each sleeper;

year of manufacture (last two digits) - for at least 20% of sleepers of each batch.

At the end of each sleeper the following is applied with paint:

quality control stamp;

batch number.

1.4.3. The locations for markings are indicated in Figure 6.

SLEEP MARKING

1 - batch number; 2 - trademark or short name of the manufacturer;

3 - year of manufacture; 4 - second grade sleeper sign

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It is allowed to apply a trademark or short name of the manufacturer and the year of manufacture on one half of the sleeper.

(Amendment).

1.4.4. Markings should be made in a font with a height of at least 50 mm.

1.4.5. At both ends of the second grade sleepers, a transverse strip 15-20 mm wide is applied with paint (see Figure 6).

2. ACCEPTANCE

2.1. Sleepers are accepted in batches in accordance with the requirements of GOST 13015 and this standard.

2.2. Sleepers accept:

according to the results of periodic tests - in terms of frost resistance of concrete and the accuracy of the geometric parameters of sleepers, with the exception of the size of type Sh1-2 sleepers;

based on the results of acceptance tests - in terms of crack resistance of sleepers, concrete strength (class of concrete in terms of compressive strength, transfer and tempering strength), condition of the bolt channels, size accuracy of sleepers type Ш1-2, quality of concrete sleeper surfaces

2.3. Periodic testing of sleepers in terms of frost resistance of concrete is carried out once a year, and in terms of the accuracy of geometric parameters - once a month.

2.4. The accuracy of the geometric parameters of the sleepers is accepted based on the results of random inspection. With the volume of the batch of sleepers St. 3200 pcs. The sampling plan should be adopted in accordance with GOST 23616.

2.5. To test for crack resistance, control sleepers are selected from each batch in the amount of 0.3%, but not less than 3 pieces. The batch is accepted for crack resistance if the sleepers selected for testing have withstood the test loads. The sleeper is considered to have passed the crack resistance test if, under control loads, no visible cracks are detected in the under-rail and middle sections. A transverse crack in concrete with a length of more than 30 mm from the edge of the sleeper and an opening at the base of more than 0.05 mm is taken as visible.

If the result of the crack resistance test is unsatisfactory, it is allowed to divide the batch into smaller ones and submit them for repeated crack resistance tests. If the result of the repeated test is unsatisfactory, it is allowed to carry out a continuous test of all sleepers in the batch.

2.6. Acceptance of sleepers based on the condition of the bolt channels and the quality of concrete surfaces is carried out based on the results of continuous inspection.

3. CONTROL METHODS

3.1. The compressive strength of concrete is determined according to GOST 10180 on a series of samples made from a concrete mixture of the working composition, stored under the conditions established by GOST 18105.

3.2. Frost resistance of concrete is determined according to GOST 10060.0 - GOST 10060.4.

3.3. The total tension force of the reinforcement is monitored using pressure gauge readings in accordance with GOST 22362 with a parallel connection of a recorder to record the tension force.

The tension force of individual reinforcement wires is measured by the transverse guy method according to GOST 22362.

3.4. To measure the linear dimensions of sleepers, as well as shells and edges of concrete, metal measuring instruments are used in accordance with GOST 13015. The depth of shells, as well as the gaps between the wires and concrete at the ends of the sleepers, are measured with a caliper with a pointed rod.

3.5. The distance between the thrust edges of the recesses of the under-rail platforms of different ends of the sleeper is measured with a template applied simultaneously to both under-rail areas of the sleeper (Fig. 7).

SIZE ACCURACY CONTROL SCHEME ( ) AND UNDER-RAIL PLATES ( AND )

1 - template or indicator device

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The distances between the edges of the recess of one end of the sleeper, between the axes of the holes for bolts and from the axis of the hole to the thrust edge are ensured by checking these dimensions on the form of metal plates that form recesses in the under-rail area when forming sleepers

X.

3.6. The slope of the under-rail platforms in the longitudinal and transverse directions to the sleeper axis (slope and propeller) is measured with an indicator applied simultaneously to both under-rail areas of the sleepers (Figures 7 and 8).

SLEEP PROPELLER CONTROL SCHEME ( )

1 - measuring device

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3.7. Deviation from straightness of under-rail platforms is determined according to GOST 13015 by measuring the largest gap between the surface of the platform and the edge of a metal straight edge.

3.8. The depth of embedding of the embedded washers into the concrete is controlled by a device inserted into the sleeper channel and rotated 90° (Fig. 9).

DIAGRAM OF A DEVICE FOR MEASURING THE DEPTH OF WASHERS

1 - handle; 2 - rod; 3 - scale; 4 - pointer; 5 - body; 6 - head

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The absence of concrete sagging in the sleeper channels, preventing installation and rotation of the bolt into the working position, as well as turning the bolt when screwing the nut, is checked with a embedded bolt in accordance with GOST 16017 with maximum positive deviations of the head dimensions. Check all four channels of the controlled sleeper

3.9. The thickness of the protective layer of concrete over the top row of reinforcement is controlled in the middle of the sleeper using the method indicated in Figure 10. It is allowed, by agreement between the manufacturer and the consumer, to control the thickness at the ends of the sleepers with a metal ruler.

SCHEME FOR MEASURING THE THICKNESS OF CONCRETE PROTECTIVE LAYER

ABOVE THE TOP ROW OF REINFORCEMENT IN THE MIDDLE OF THE SLEEPER

1 - rail; 2 - wire of the upper row of reinforcement

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3.10. The height of the sleeper is checked with a caliper in cross sections in the middle of each under-rail platform and in the middle of the sleeper.

3.11. Each sleeper selected for crack resistance testing is tested with static load sequentially in the under-rail and middle sections according to the diagrams shown in Figure 11.

SCHEME FOR TESTING SLEEPERS FOR CRACK RESISTANCE

in the under-rail section

in the middle section

1 - steel plate with a lower base slope of 1:20, size 250x100 mm, average thickness 25 mm;

2 - steel plate measuring 250x100x25 mm; 3 - rubber gasket measuring 250x100x10 mm;

4 - steel roller with a diameter of 40 and a length of 250 mm

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The load is evenly increased with an intensity of no more than 1 kN/s (100 kgf/s) and brought to the control value indicated in Table 2. This load is maintained constant for 2 minutes, after which the side surfaces on both sides of the sleeper at the tested section are inspected in order to detect visible cracks in the tension zone of the concrete. The surface of the concrete is not wetted. Illumination of the concrete surface is at least 3000 lux. To measure the length of cracks, a metal ruler is used, and for the width of cracks, a measuring magnifying glass is used in accordance with GOST 25706 with a division value of 0.05 mm.

3.12. The list of devices, indicators and templates for monitoring the geometric parameters of sleepers is given in Appendix 3.

3.13. All non-standardized measuring and testing instruments must undergo metrological certification in accordance with GOST 8.326*.

________________

* PR 50.2.009-94 applies on the territory of the Russian Federation.

4. TRANSPORTATION AND STORAGE

4.1. Transportation and storage of sleepers should be carried out in accordance with the requirements of GOST 13015 and this standard.

4.2. Sleepers should be transported and stored in stacks in horizontal rows in the working position (sole down). The stack height should be no more than 16 rows.

Pads for sleepers and spacers between them in a stack should be placed in the recesses of the under-rail areas of the sleepers. The thickness of wooden linings and gaskets must be at least 50 mm. It is allowed, by agreement between the manufacturer and the consumer, to use wooden spacers with a cross-section of at least 40x40 mm when located at a distance of 30-40 mm from the thrust edges of the recesses in the under-rail areas of the sleepers.

4.3. Sleepers are transported in gondola cars or cars. Transportation of sleepers of different brands and varieties in one gondola car or vehicle is not allowed.

5. MANUFACTURER WARRANTY

5.1. The manufacturer guarantees that sleepers comply with the requirements of this standard provided that the consumer complies with the rules for their operation, transportation and storage.

5.2. The warranty period for sleepers is three years from the date of their installation. The calculation of the warranty period begins no later than 9 months from the date of receipt of the sleepers by the consumer.

ANNEX 1

Mandatory

INDICATORS OF MATERIAL CONSUMPTION OF SLEEPERS

Indicators of material consumption of sleepers manufactured using standard flow-aggregate technology in ten-cavity molds (without taking into account technological and production losses outside the mold):

embedded washers

11.8 kg

APPENDIX 2

SPACER

Material - St 3.

Thickness - 1 mm.

Weight - 0.037 kg.

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APPENDIX 3

Information

LIST OF DEVICES, INDICATORS AND TEMPLATES

TO CONTROL THE GEOMETRICAL PARAMETERS OF SLEEPERS

To control the geometric parameters of reinforced concrete sleepers, it is recommended to use a set of devices, indicators and templates developed by the Industroyproekt Institute and adopted by the USSR Ministry of Construction Materials Industry.

Electronic document text

prepared by Kodeks JSC and verified against:

official publication

M.: IPK Standards Publishing House, 2004

A sleeper is a support for railway rails that maintains their relative position unchanged. It takes the pressure from their weight and transfers it to the sleeper base, consisting of a layer of ballast made of crushed stone or concrete, then to the ground. It is made of wood, plastic, steel, reinforced concrete. They are installed on every kilometer of tracks in quantity (three options): 1600 on secondary roads, 1840 or 2000.

Precast concrete products have found particularly wide application in the construction of continuous (velvet) railway tracks. These are roads on which the distance between rail joints is much greater than the length of a standard rail (25 m). Such tracks differ from conventional ones in the higher cost of installation work due to the weight of the elements, but they provide maximum train speed, convenience for passengers, and reduced maintenance costs.

Sleepers are solid beams (bars) of variable cross-section with platforms for installing rails. They are made from stressed reinforced concrete. This is a structure with prestressed (prestressed) steel reinforcement inside. It differs from conventional reinforced concrete products in its ability to withstand significant tensile loads and prevent the appearance of cracks and splits under their influence. This material is also called prestressed (labeled polyconcrete reinforced concrete). Its use allows the use of smaller products, saving on reinforcement, concrete and transportation costs, and simplifies installation. Weight of 1 piece - 270-285 kg (depending on the weight and number of reinforcing bars).

The production of rail supports is carried out in accordance with the requirements of GOST 10629-88 and 54747-2011. Standard dimensions of a reinforced concrete support: length - 2700 mm, width - 300, height - 230, height in the middle section - 160 mm, height at the ends - 185 mm.

Concrete is used with strength grades from B40 (M500) and higher, frost resistance grades of at least F200. As a filler for the mixture, only crushed stone from natural stone or gravel with a grain size of 5-20 mm is used. By agreement with the buyer, in order to reduce the cost per unit, it is allowed to add a fraction of 20-40 mm in an amount of no more than 10% of the volume of the main one (5-20).

For reinforcement in the production of these reinforced concrete structures, periodic or smooth carbon steel products are used:

• cold-deformed wire with a diameter of 3 to 8 mm;
• cold-deformed rod reinforcement with a diameter of 8 to 10;
• hot-rolled and heat-treated rod reinforcement from 8 to 10;
• reinforcing ropes from 6 to 14.

Smooth reinforcement can only be used in conjunction with end anchors.

Advantages and disadvantages

Advantages of reinforced concrete sleepers:

• long service life - at least 30 years;
• no rotting or corrosion;
• resistance to atmospheric and mechanical influences;
• high resistance to movement;
• simplicity of installation technology;
• dimensional accuracy, weight stability;
• possibility of use on the busiest sections of tracks;
• dismantling and reinstallation.

Disadvantages of reinforced concrete supports:

• weight of 1 piece - not less than 270 kg;
• the need to use special equipment;
• relatively high price of a new product;
• increased rigidity, require special elastic gaskets;
• the possibility of destruction of concrete, the need for periodic inspection;
• high electrical conductivity, use of insulation.

Kinds

On the platform for installing rails (under-rail platform) there are holes for fastening to the rail and connections to the adjacent support.

Sleepers are classified according to the type of rail fastening:

• Ш-1-1 - separate terminal-bolt fastening type KB, with an angle of inclination of the thrust edges of the under-rail platforms of 55°;
• Ш-1-2 - separate terminal-bolt type, with an angle of inclination of the thrust edges of the under-rail platforms of 72°;
• Sh-2 - inseparable terminal-bolt fixation with bolted fastening to the gasket or rail;
• Ш-3 - continuous terminal-bolt fixation with bolt fastening to the rail;
• Sh-5-DF - screw-dowel fastening;
• ShS-ARS - anchor rail;
• Pandarol-350 (Fastclip) - have a special anchor fastening developed by the British company of the same name for high-speed (350 km/h) and heavy-duty railway traffic.

According to the features of application and installation, the following types of reinforced concrete rail supports are distinguished:

• pavement (M) - for laying on bridges;
• shuttle (CH) - for shuttles on bridges;
• for curved sections (K) - radius less than 350°;
• Sh-3-D 750 - for children's railway (for a track width of 750 mm with rails of type R-43);
• transformer - for constructing transfer paths for power transformers at electrical substations, differs from other types in that it has a rectangular cross-section along the entire length;
• bars for turnouts;
• half sleeper - for rail tracks intended for moving cranes along them;
• for sections with a combination of two different track widths - two varieties: for three or four rail lines.

To ensure insulation, sleeper manufacturers offer products with special void-forming liners.

Depending on the dimensional accuracy, quality of the concrete surface and resistance to cracking, rail supports are classified into two grades. The products of the second can be purchased for use on access roads, stations, other lightly loaded tracks of class 5 and internal roads of industrial enterprises.

Before purchasing a batch of reinforced concrete rail supports, it is recommended to inspect several sleepers. There should be a stamp with markings on the top surface of a quality product. It contains the trademark or abbreviated name of the manufacturer. The end part is marked with a quality control inspection mark and the batch number. Every fifth element indicates the last two digits of the year of manufacture.

Products of the second grade (in terms of crack resistance and geometry) are supplied only at the request of the buyer. A transverse line 1.5-2 cm wide is applied at both ends with indelible paint. If there are two such stripes on each side, it means that the sleeper does not meet the standard requirements even for the second grade.

Be sure to evaluate the number and nature of defects. Allowed presence:

• imprints from welds on the longitudinal edges of under-rail areas;
• traces at the ends - no more than 5 mm deep.

Not allowed:

• sagging in the bolt channels, preventing their installation and free rotation;
• surges on under-rail areas;
• turning bolts;
• cracks;
• protruding reinforcement rods (if wire was used for reinforcement, then its ends should extend beyond the end by no more than 2 cm).

Maximum permissible dimensions of cavities and beads on reinforced concrete sleepers of the first grade:

For the second grade, defects with dimensions twice as large as those of the first are allowed.

Reinforced concrete sleepers

Reinforced concrete sleepers in Russia. Today, there is a certain upward trend in the market for the production and sales of reinforced concrete sleepers, even despite the global economic crisis. According to marketers, the positive dynamics of demand for concrete sleepers is expected in the future. Competition between enterprises will also increase - competition for new orders and new customers. This competition forces us to pay the utmost attention to proposals for the supply of reinforced concrete sleepers. We do not pursue excessive profits, therefore, by contacting our company you will receive the most advantageous offer that corresponds to the present time. Our prices become most relevant when supplying reinforced concrete sleepers to the central regions of the Russian Federation.

These reinforced concrete sleepers are intended for the construction of a general network of 1520 mm gauge railways and are produced in accordance with GOST 10629-88. Reinforced concrete sleeper Ш1 (1Ш 27-ВР1500-КБшз) - used with rails of type Р75, Р65, Р50 with rail fastening type KB (separate clamp-bolt type) with bolted attachment of the gasket to the sleeper (separate type Ш1). The sleepers are reinforced with BP II wire, 3 mm in cross section.

Technical characteristics of reinforced concrete sleepers type 1Sh 27-VR1500-KBshz:

• Product weight - 0.270 t.
• Concrete volume - 0.108 cubic meters.
• Concrete class - B40
• Concrete grade for frost resistance - F200
• Length - 2,700 mm, width - 300 mm, height - 230 mm.

Manufacturers of sleepers: a modern factory of reinforced concrete sleepers offers supplies of its products!

The modern plant of reinforced concrete sleepers offers supplies of its products at competitive prices. Sleeper manufacturers ship these products by rail, the loading rate for one gondola car is 240 pcs and 256 pcs.

In a railway track, reinforced concrete sleepers are laid on the ballast layer of the upper structure of the track and ensure that the relative position of the rail threads remains constant, they receive pressure directly from the rails or from intermediate fastenings and transfer it to the undersleeper base (usually the ballast layer).

Reinforced concrete sleeper Ш-1-1 - Drawing

Reinforced concrete sleepers

Reinforced concrete sleepers are divided into several categories depending on the possibilities of their use. What is common is the production principle. Ready-made reinforced concrete sleepers are beams made of reinforced concrete that have previously undergone a tension procedure (to increase strength). Sleepers are produced taking into account resistance to cracking and are frost-resistant. The design life of reinforced concrete sleepers is approximately 50 years.

Reinforced concrete sleeper Ш-1-1 (grade 1)– element of the upper structure of the railway track. It is a beam made of stressed reinforced concrete. Heavy concrete of the highest category is used in production.

Compared to wooden sleepers, a reinforced concrete product has the highest performance characteristics: increased strength, resistance to cracking, frost resistance, long service life (up to 50 years).

This type of sleeper Ш-1-1 designed for terminal-bolt rail fastening of the design unit with bolted fastening of the lining to the sleeper. Used for laying broad gauge railways (1520 mm), with rails P50, P65, P75.

Reinforced concrete sleepers Ш-1-1 are much heavier and stronger than wooden ones, therefore they are used in the construction of highways and other routes with high traffic.

The only drawback of such products is their high cost.