JPS5829363B2 - Kidney injury and child abuse - Google Patents

Description

Detailed Description of the Invention The present invention relates to a track paving method in which an injection layer is placed between the track ties and the ballast.

In recent years, with an increase in rail transport volume, the number of trains passing through has also increased, which has resulted in an increase in the frequency of track maintenance work, particularly on the trackbed.

On the other hand, as the number of trains passing through increases, the time available for maintenance work decreases, so a track system that can reduce the labor required for maintenance work has become necessary.

That is, methods such as using a concrete track bed instead of the conventional ballast track bed or integrating the ballast track bed are being considered.

The object of the present invention is to provide a grouting material suitable for a new track construction method in which a layer of grouting material is placed between the track sleepers and the track bed, which is different from the improved track bed.

The grouted material in this track structure distributes the various stresses caused by passing vehicles through the sleepers evenly to the ballast, which is the substructure. At the same time, it absorbs as much of the vibrations transmitted through the sleepers as possible, mitigating the impact force on the ballast, protecting it, reducing wear and tear on the crushed stone, and extending the maintenance work cycle.

The above-mentioned injection material is required to have the following physical properties:

In other words, it is desirable that the sleepers should not deform more than necessary throughout the year in response to the compressive stress transmitted through the sleepers, and on the other hand, if they are too hard, they will not be able to absorb vibrations sufficiently.
Lil.

Furthermore, when injecting the injection material between the sleepers and the ballast, if it is poured in liquid form, it will be difficult to inject it between the sleepers and the ballast.

Therefore, a material is required that is liquid during operation, is strong after hardening, deforms little under compressive stress, and has good vibration absorption properties.

The inventors further numerically specified various necessary conditions based on train running conditions and produced a number of experimental injection materials.
In addition to investigating its characteristics, a model track with one sleeper, 2 m wide and 0.5 m long, was used. The injection material was injected between the sleeper and the ballast. After hardening, a static load of 4 tons and a vertical vibration load of 4.5 toH were simultaneously applied to the sleeper.
It was found that by conducting a vibration experiment 100,000 times to confirm the deformability of the injected material, the required characteristics of the material can be determined from the relationship between the material characteristics and the amount of deformation of the injected material by the vibration experiment.

Furthermore, experiments were carried out on the injection properties depending on the injection materials and injection conditions, and it was found that the viscosity of the injection material during injection is an important determining factor for the injection properties.

Regarding grouting workability, it is preferable that the grouting material is injected in a liquid state between the sleepers and the ballast to form a layer, which has the advantage of being easy to work with and can be set according to the level of the sleepers.

Regarding the injection temperature, since the injection material comes into contact with concrete products, crushed stone, etc., it is desirable to carry out the injection at a temperature of 200°C or less in order to prevent damage to the concrete, etc. Furthermore, in consideration of the injection workability, etc., it is desirable to carry out the injection at a temperature of 200°C or less.
A pouring material having a value of 30 bores or less at the following temperatures may be used.

However, as mentioned above, the properties required of the injection material are not only ease of injection but also, more importantly, the properties during use.

When we look at the state in which the injection material will be used after it hardens,
The mechanical properties of the grouting material during its service must be considered in terms of the temperature conditions.

Temperature conditions are particularly problematic in the summer.

In this regard, the inventors observed the temperature distribution in summer using a track model and found that the maximum temperature under the sleepers was 40°C.
It turned out that it would be sufficient to consider the following.

From this, the deformation resistance of the injection material during use is 4
It should be noted that sufficient performance is not shown when viewed at 0°C.

There are various forces acting on the grouting material through the sleepers, but the main ones are compressive stress and shear stress. The most important property required of the grouting material is the ability to withstand compressive stress.

The compressive stress acting on the injection material through the sleepers is mainly due to the impact force caused by the stationary load of the train and the irregular movement caused by its movement. Since this impact force is a combined force of various conditions such as the condition of the vehicle side, the track side, and the running speed, it is extremely difficult to fit it into a single framework.

For this reason, it is not sufficient to consider only the elastic modulus as a property of the injection material; the property must also take into account the concept of loading speed.

The inventors have investigated the properties of various materials, i.e., thermoplastic materials and reaction-hardening materials, and conducted the load vibration experiment described above. As a result, it has been found that the compressive stress value at 10-fold strain under compressive conditions with a strain rate of 1.5%/min at 40°C is appropriate as the material property that correlates with the amount of deformation of the injected material at the end of the load vibration experiment. Furthermore, as a result of the vibration experiment, it has been found that this compressive stress value is 0.4 K7/cr.
It was found that if the load is above tt, there is almost no deformation of the injection material during use throughout the year.

For example, the track sleeper is 73.3CW1, sleeper spacing is 10
(If the load is 771, it has been experimentally clarified that the load under the center of the sleeper due to the passage of a train is approximately as follows:

In other words, when 9 rails are used for 50, although the train speed also has an effect, compressive stress begins to be applied when the wheel load reaches approximately 2.5 to 3.0 m before the target loading point, the maximum compressive stress is experienced when the wheel comes over the target loading point, and the stress is then relieved.

On the other hand, when the injected material is a viscoelastic material, the situation is more complex than when it is an elastic material, and the deformation resistance when subjected to compressive stress is affected by the loading rate, with a slow rf loading rate being weaker than a fast rate.

So to be on the safe side, a slow loading rate was adopted here.

In other words, if the maximum deformation when a train runs at an extremely slow speed of about 25 m/hr is 10 times, the
It is appropriate to use a strain rate of min.

On the other hand, from the viewpoint of protecting the lower ballast, it is preferable that the compressive stress is not too high, since this would adversely affect vibration absorption, and it is desirable that the compressive stress exhibits a value of 30<q/c4 under the above strain line conditions.

The present invention provides an injection material to be injected between the sleepers and the ballast that has a viscosity of 30 poise or less at a temperature of 200°C or less before hardening, and has properties of 40% or less when hardened and in service after injection.
Under compression conditions of a strain rate of 1.5 kPa/min at 0°C, the compressive stress value at 10 kPa is 0.4 to 30 Kq/cr.
It resides in materials that exhibit a value of rt.

The injection material according to the invention may be a thermoplastic or reaction-hardening material, as set forth in the appended claims.

For example, thermoplastic materials include various petroleum-based, natural, or synthetic waxes, various bitumens such as asphalts, pitches, and tars, thermoplastic resins such as polyethylene, polypropylene, polystyrene, polyvinyl acetate, ethylene-vinyl acetate copolymer resins, polybutene, ethylene-propylene copolymer resins, and sulfur.

Furthermore, the above-mentioned various materials can be used alone or in combination of several materials, and further, for example, various fibers, fillers, oils, rubbers and other additives may be added.

Example 10/20 A completely melted mixture of 16 tons of flon asphalt and 4 tons of low molecular weight polyethylene (average molecular weight about 700) had a viscosity of 5 poise or less at 2000C and a compression strain rate of 1.5%/min at 40°C.
The compressive stress at 10 strain in n is 0.62 n/cr
It was A.

This material was used on the Kansai Main Line over a 75m section, with concrete sleepers 73.3 (?771) wide and ballast bed (after compacting the ballast bed, 6 frame stones (diameter 121rL11
L) was sprayed and compacted into the roadbed, and then injected at a temperature of about 180°C as the injection material for an injection layer about 2 cm thick, after which it was allowed to cool and harden before being used.

As a result, from March 1974 through the summer of that year until October, no deformation had occurred at all in the injection layer.

FIG. 1 shows a cross-sectional view of this embodiment, in which 1 is a sleeper and 2 is an injection port for injection material provided in the sleeper, the upper end of which is 8 cm in diameter.
The lower end is trumpet-shaped and circular, with a diameter of 6 cm.

3 is the injection layer, 4 is the rail and 5 is the ballast bed.

FIG. 2 is a plan view of FIG. 1, showing the fastening device 6 which also serves as a washer for the rail and which secures the rail to the sleepers.

[Brief description of the drawings]

FIG. 1 shows a cross-sectional view of one embodiment of the present invention, and FIG. 2 shows a plan view of FIG. 1. 1... sleeper, 2... material injection port, 3... injection layer,
4: rail, 5: ballast bed, 6: fastening device.

Claims (1)

[Claims] A method for paving track in which a layer of injection material is placed between the sleepers and the ballast, the method comprising the steps of: injecting an injection material which has a viscosity of 30 poise or less at a temperature of 200°C or less before hardening, and which, when hardened after injection, has a compressive stress of 0.4-300/cm at 10 strains under compression conditions of a strain rate of 1.5% per minute at 40°C, and which is made of at least one component selected from the group consisting of petroleum-based, natural or synthetic waxes, various bitumen, polyethylene, polypropylene, polyethylene, polyvinyl acetate, ethylene-M2 vinyl copolymer resin, polybutene, ethylene-propylene copolymer resin and sulfur.