Railway sleepers - the most important structural element corresponding line.Their quality directly depends on the stability of the infrastructure.In Russia, used wooden and concrete structures.Concerning them set a number of important standards that define the dimensions.What is their specificity?
Classification wooden sleepers types
Dimensions sleepers made of wood, in accordance with the state standards, should correlate with its type.There are several reasons for the classification of the element of the railway.
Among the most common - the appointment.Thus, the sleeper are divided into those that are designed to:
- main track 1, Grade 2, or 3rd, provided that their traffic density exceeds 5 million. T / km per year, or operated at a speed trains exceeding 100 km /h;
- main lines 3 and 4 class of access (to the intensive work), sorting, and receiving-- stations;
- any ways that are attributable to the class 5, including the station, belonging to the category of low-density, as well as other that are characterized by shunting export-type movement.
Given the variety of ways are arranged in use, respectively, I, II and III types of sleepers.With respect to these set thus standardized performance.
Factor humidity
actual size of railway sleepers made from wood, may depend on the moisture level of the material.What does it mean?The fact that the corresponding values for the relevant humidity not exceeding 22%.If this figure more than the specified value, the size of the tie should be treated with the necessary allowances for shrinkage.Its value depends on the type of wood - coniferous or deciduous.A similar requirement is also in respect of cross-sections of composite railroad ties.
Tolerances dimensions composite sleepers
size sleepers may deviate from the standards laid down in state standards, within the permissible values.Regarding the length - is 20 mm thickness - 5 mm.There are also tolerances, correlated with the width of faces, tall sides, the distance between the bolts, as well as their vertical axis from the sleepers.
Standardized sizes of wooden sleepers
Consider now, in fact, what could be the size of the wooden sleepers (railway) depending on the type.
As for the railway line elements of type I, the values should be such:
- thickness - 180 mm (tolerance of 5 mm);
- sawn sides height - 150 mm;
- width of the upper layer - 180-210 mm;
- the width of the lower layer - 250 mm (tolerance of 5 mm);
- length - 2750 mm (permitted adjustment range of 20 mm).
Regarding the sleepers of type II, its dimensions must meet the following criteria:
- thickness - 160 mm (tolerance of 5 mm);
- sawn sides height - 130 mm;
- width of the upper layer - 180-210 mm;
- the width of the lower layer - 230 mm (allowed deviation of 5 mm);
- length - 2750 mm (allowed to change within 20 mm).
In turn, sleepers type III must comply with the following parameters:
- thickness - 150 mm (allowed deviation of 5 mm);
- sawn sides height - 105 mm;
- width of the upper layer - 140-190 mm;
- the width of the lower layer - 230mm (permitted deviation of 5 mm);
- length - 2750 mm (allowed adjustment range of 20 mm).
We have examined the requirements for the size of wooden railway sleepers that set state standards.But the structure of the railway track there is another important element of the wood used in addition to the sleepers - switch ties.Investigate, in turn, the standards that are set by the state in relation to their size.
Dimensions switch ties Criteria
as the size of the tie, the corresponding figures for the frames are defined by their type.The grounds for the classification of the element of the railway track as a few.Among the major, as in the case when determining the size of sleepers - appointment.
Thus, the boards can be used:
- on the main routes 1, Class 2 or the third, characterized by traffic density in excess of 50 million tons / km per year, as well as the speed of the trains of more than 100 km / h;
- on the main ways of relating to the 2, 3 and 4 classes of access (to the intensive work), as well as sorting and receiving-that are present at the stations;
- in the ways that are attributable to the class 5, including the station are classified as low-density access and other, characterized by the movement of shunting-export type.
The specified paths correspond to I, II and III types of switch ties.
As in the case of ties, is set humidity value.For example, the standardized dimensions of switch ties, characterized by the humidity indicator more than 22%, should be considered with regard to the necessary allowance for drying.As is the case with the standards determined by the size sleepers in this case is important, what kind of wood species used for the manufacture of the boards - softwood or hardwood.In the first case, the necessary criteria contained in GOST 6782.1-75, in the second - the visitors used 6782.2.-75.
Learn how and when we examined the wooden sleepers, size bars correlative to their type.
Dimensions switch ties types
When it comes to the bars of type I, their characteristics must meet the following values:
- -180 mm thickness (allowed adjustment in the range of 5 mm);
- width of the upper layer - 220 mm (broadened), 200 mm (wide);
- the width of the lower layer - 260 mm;
- sawn side height - 150 mm.
- the width of the timber at nepropilennym elements - 300 mm;
Bars Type II should have the following characteristics:
- -160 mm thickness (permissible deviation within 5 mm);
- the width of the upper layer of 220 mm (br) - 175 mm (normal);
- the width of the lower layer - 250 mm;
- sawn side height - 130 mm.
- the width of the timber at nepropilennym elements - 280 mm;With regard
bars Type III, the following standards:
- thickness - 160mm (permitted deviation within 5 mm);
- width of the upper layer - 200 mm (wide), 175 mm (normal);
- the width of the lower layer - 230 mm;
- sawn side height - 130 mm;
- the width of the timber at nepropilennym elements - 260 mm.
length of the boards: range of acceptable values
But what are the indicators of the length of the bar?In contrast to the standards governing the size of the wooden sleepers (railway) when all the values depend on the type of the corresponding element, suggest quite strict compliance with established standards, in the case of timber - the length of the criteria common to all types.Moreover, the standards do not set a specific indicator and the interval - from 3 to 5.5 meters with graduations of 0.25 m with allowed variations within 20 mm.
Bridge beams: the specificity of standardization
So we looked at what the standards governing the dimensions of wooden railway sleepers (railway) and supplementing it in the structure of the railway beds timber.But there is another important component of the respective routes.It is a bridge bars.Just as governed by the size of railway-sleepers, the figure for the component in the railway beds are also recorded in the state standards.We will study this more specifics.
Material of bridge beams - wood.Their size corresponds to one parameter - the size of the cross-section and admissible indicators of deviations.The main requirement for timber - a rectangular shape.Relevant elements of railway lines are cross-section:
- 220 x 240 mm;
- 220 to 260 mm.
Bridge boards of both types, however, must have the same length - 3250 mm.But in terms of standardization of tolerances indicators may vary.Thus, for beams with a cross section of 220 x 240 mm maximum deviation can be: minus 2 mm (thickness) 15 mm (length).Regarding the second type of rail elements other indicators.Thus, adjusting the thickness to 220 bars with a cross section of 260 mm are not provided, as well as in length, but the width corresponding to the value that is set in the standard, of 3 mm.
It may be noted that the agreement with the customer can be made with other sections of the bars - 220 280 240 and 300 mm, having a length of 4.2 m.
As is the case with the standards governing the size of the wooden sleepers (railway), indicators of the length of the bridge beams are installed for the product within the specified humidity levels.In this case - 20%.If the bridge beams will have more moisture, it is necessary to consider the size requirements with the necessary allowances for shrinkage - in accordance with GOST 6782.1-75.
concrete sleepers: classification
alternative to wooden ties can be reinforced concrete.These products are utilized on the main roads.Falls into the category of pre-stressed.Are utilized for laying rail types P75, P65 and P50.There are many reasons for the classification of concrete sleepers:
- by type of bonding with rails;
- varieties of tendons;
- by an electrically insulating characteristics;
- in terms of workmanship.
In this case, we are interested in the first criterion - the way in which is secured to the concrete rail sleepers.Product dimensions and other important characteristics is determined based on the characteristics of an appropriate mechanism.Thus, depending on the type of fastening of the rails to the sleepers are:
- SH1 type intended for using a separate fastening bolts by fixing the lining on the sleeper;
- type Sh2 intended for inseparable bond with bolts through the attachment to the tie not only liner but also the rail;
- Nd3 type intended for inseparable bond with bolts by direct attachment to the tie rail.
Concrete Sleepers: dimensions and other parameters
important criterion that determines the required parameters concrete sleepers - its assignment to one of the above types.
So, when it comes to tie classified as SH1, it must have the following characteristics:
- required distance between the stop edge - 2016 mm;
- the distance between the edges of the end product - 406 mm;
- the height of the product to under-rail section - 193 mm;
- the height of the product in the middle section - 145 mm.
Sleeper type R2 must have the following characteristics:
- the distance separating the thrust edge - 2016 mm;
- the distance between the edges of the end product - 406 mm;
- the height of the product to under-rail section - 193 mm;
- the height of the product in the middle section - 145 mm.
Sleeper, classified as R3, must meet the following criteria:
- the distance separating the thrust edge - 1966 mm;
- the distance between the edges of the end product - 359 mm;
- under-rail section height - 193 mm;
- height in the middle section - 145 mm.
These are the main characteristics that, in accordance with state standards, must have concrete sleepers.Its dimensions in terms of length and breadth often fixed - respectively 300 and 2700 mm.Deviations comparable with those recorded for wood products for concrete elements in the state standards is not provided.Size railway sleepers corresponding type of variation does not imply correlative with humidity and other environmental factors.
wooden and reinforced concrete sleepers: commonalities and key differences
What other fundamental differences can be noted between the concrete and wooden elements?First, what is the difference, so the tie - size.Weight - is also a significant criterion of dissimilarity of the relevant products.The index for wooden sleepers - about 80-85 kg of concrete - about 270 kg.Scope and those and others not so much different.Sleepers, timber, dimensions of which we investigated in the first place?historically preceded reinforced concrete, but still has not lost its relevance.Moreover, they have a number of important advantages - a low cost, ease of transportation, replacement and transportation, resistance to stress.
