JPS59130910A - Strengthening work for ground of track - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a railway ground reinforcement method, more specifically, a flexible bag is fixed to a pipe body, and an injection material is injected into the bag to inflate it. This invention relates to a construction method for strengthening railway ground that is frequently exposed to dynamic load vibrations due to the effects of increasing the density of the surrounding ground and increasing frictional resistance due to the bulging body.

[Background technology of the invention and its problems]

Generally, railway tracks have a structure in which the rails and sleepers are connected using dog nails, etc. on the ground and are fixed with track bed ballast, so the repeated loads of passing trains can cause various changes in various parts of the track, especially in the track bed. When deformation occurs, track deviation occurs, and when it becomes large, it causes a lot of turbulence in the queue, making the ride uncomfortable, and forcing trains to move slowly, which has a negative impact on the time and economy of operation. Furthermore, in rare cases, it may cause a train derailment accident, so maintenance must be maintained to ensure that track deviations are always within at least a certain limit.

Various types of displacement and deformation of the road bed are caused by the road bed itself or by the earth road bed supporting the road bed, and the present invention aims to strengthen the latter earth road bed.

By the way, the train load and vibration when a train passes is finally transmitted from the rails to the roadbed through the piles and the roadbed, and the natural ground under the roadbed supports the roadbed. Therefore, the roadbed and its supporting ground serve as the foundation of the track, but while the foundations of general structures are subject to static loads, railway roadbeds are characterized in that they are subject to dynamic loads and vibrations. Since the railway bed is theoretically subjected to a large pressure of 20 tons/kg or more, it is necessary that the ground is quite good. However, when the supporting ground is soft ground and the roadbed is a low embankment, the roadbed is constantly subjected to intense dynamic load vibrations under natural conditions, making it unstable. If the roadbed is unstable, track deviations are likely to occur, which not only requires a lot of effort and frequent material replacement for maintenance, but also
Train operating speed will decrease and train vibration will increase. In particular, ground with a high groundwater level and poor soil quality, diluvial volcanic ash viscous soil, sandy soil with a risk of fluidization, fine grained soil, lakes, marshes, sea candles, etc. If the roadbed is constructed with low embankment on the ground - H, the phenomenon described in 1-H will occur. In general, the influence of train load depends on the ground, but the depth is 4 to 5.
It is m.

Conventionally, as countermeasures against these problems, the replacement method, sheet pile method, chemical injection method, and pile driving method have been used.

The replacement method can only perform surface treatment, and it is difficult to perform 4 to 5 m. The sheet pile method only prevents the ground from flowing by driving sheet piles on both sides, but it is not a complete solution to the issue. The chemical injection method is not suitable for improving viscous ground. The pile driving method requires driving pine piles and concrete piles to the supporting layer, which requires a considerable length and number of piles, and is difficult to construct on commercial lines. There are many aspects of the 1'L construction method that can be improved in the future in terms of economy and effectiveness. In particular, with the chemical injection method, there is a risk that the ground may rise due to the injection of the injection material. In addition, ground improvement on service lines is subject to time constraints, so construction must be done quickly and effectively.

[Purpose of the invention]

The present invention was proposed in consideration of the above-mentioned problems, and its purpose is to enable quick construction even on commercial lines without hindering train operation, to be economical, and to be easily improved. It is an object of the present invention to provide a method of reinforcing the track ground that can reliably prevent track subsidence and alleviate train vibration.

[Summary of the invention]

The method of the present invention to achieve this objective includes arranging a plurality of fusible sleeve-like bags in the axial direction on the outer wall of the tube, forming an injection port on the outer wall of the tube corresponding to each bag, and furthermore, Prepare an integrated antibody with a cone-shaped ballad cut 9 whose diameter is smaller than the outside diameter of the tube body at the tip of the body; directly into the target track ground without inserting a casing pipe. It is characterized in that the injection material is press-fitted at a predetermined depth, and then the injection material that is pumped from the base of the tube is injected from the injection port to inflate the bag body, and in this state, the injection material is hardened to form an antibody. It is.

Conventionally, Japanese Unexamined Patent Publication No. 53-126710 discloses a method in which a flexible bag is provided around an injection tube and the bag is inflated with an injection material.

However, this construction method does not take into consideration the situation with the track ground. In other words, this method requires a complicated and time-consuming process in which a casing pipe is inserted in advance, an injection pipe is inserted inside the casing pipe, the casing pipe is pulled up, an inner pipe with a packer is inserted, and the injection material is injected. The method has been adopted. Therefore, as mentioned above, it is practically impossible under the requirements of rapid construction during train service hours. Furthermore, because this construction method focuses only on the bulging effect of the bag, it cannot be adequately applied to railway ground that is frequently exposed to severe dynamic loads and vibrations.

On the other hand, in the present invention, in addition to the consolidation effect due to the expansion of the bag, a high axial force is achieved by press-fitting the tube and increasing the frictional resistance between the circumferential surface and the surrounding ground. Furthermore, by integrating a cone-shaped ballast cut into the light body of the tube body, it is possible to deal with press fitting, and by making the diameter of the ballast cut smaller than the outer diameter of the tube body, the difference in diameter can be reduced. [Specific Examples of the Invention] The present invention will be specifically described below with reference to the drawings.

1 is natural ground, and after embankment 2 is carried out, road bed ballast 3 is laid down, and stakes and rails are installed on top of it.

Improvements are made to such railway ground using the following antibodies. That is, a conical ballast cut Q5 made of steel and having an opening angle of about 60 degrees, for example, is integrally welded to the tip of the steel tubular body 4. Rubber sleeves 6 are wrapped around the tube body 4 at intervals in the longitudinal direction, and cover an injection lower 7' formed in advance on the tube body 4, and are discharged from both ends of the injection lower and the rubber sleeve 60. This is to prevent the injection material from flowing back into the tube body 4. A flexible bag 8 is disposed to enclose the injection lower and rubber sleeve 6, and is fixed to the tube body 4 at both ends with fixing bands 9. For this fastening, as shown in FIG. 3, ribs 10, 10 are formed on the tube body 4, an elastic band 11 is wrapped inside the ribs, and the end of the flexible bag body 8 is attached to the upper part of the ribs 10, 10. After covering it, it can be fixed with a fixing band 9 such as a binding wire.

Furthermore, it is burdensome to have a dummy steel pipe 13 connected to the base of the tubular body 4 via a socket 12.

Thus, during construction, the vinyl chloride pipe 14 or the like is installed in the trackbed ballast 3 as a guide pipe.

Next, the eyebrow body 4 and the dummy steel pipe 13 are press-fitted into a press-fitting machine to a predetermined depth. During press-fitting, since the ballast cut 5 is provided, press-fitting becomes smooth. If necessary, the guide pipe may be omitted and the trackbed ballast may be directly cut and press-fitted.

Thereafter, the dummy jiij pipe 13 is removed from the socket 12, and an injection pipe is connected to the socket 12K in its place. Next, an injection material such as cement is pumped through the injection pipe and discharged through the injection lower. The injection material from injection 1] 7 is forced out into the flexible bag body 8 from both ends of the comb sleeve 6 while bending it. Furthermore, injection of injection material up to a predetermined amount is continued in each flexible bag body 8, 8. ...It is made to bulge as shown in Figure 1, thereby consolidating the surrounding ground and waiting for it to harden in this state. When the injection material is completely cured, a plurality of knobby antibodies are formed around the tube. The injection tube will be removed at an appropriate time.

This antibody is caused by the compaction and frictional effects of the bag body 8, the tube body 4
According to experiments conducted by the present inventors, due to the friction effect between the pile and the surrounding ground, and the anchor effect due to the ballast cut υ5, the axial force is more than three times that of ordinary steel pipe piles, which is an excellent improvement effect. It has been found that 0 By the way, it is desirable to use a steel pipe as the above-mentioned pipe body in terms of strength, and -! The diameter of the O reinforcement shaft is selected depending on the construction pitch or ground condition, etc., but it is preferable that the diameter is 50 to 50 mm. O reinforcement shafts are constructed between rails and between piles, but the construction pitch at this time depends on the roadbed condition, etc. For example, 1 mm from a staggered 50c silkworm.
A moderate pitch is desirable.

The material used for the bag body is cloth, for example, canvas cloth, nylon cloth, rubberized cloth, or the like. The bag may be any material that deforms before and after the injection of the injection material, and the deformation may be caused by elongation like rubber. The bag may be either water-permeable or water-impermeable, such as rubber or plastic. When using a water-permeable old material such as cloth, it should be coarse and smooth enough to prevent the solid content of the injection material (for example, cement) from penetrating it. This is because inflation of the bag cannot be achieved. However, since all that is required is for the bag to expand, it is also possible to strengthen the surrounding ground outside the bag by the expansion effect of the bag and the effect of injecting a chemical solution into the surrounding ground by allowing some of the water and cement to pass through the bag. good.

In the case of water-permeable materials with holes that allow water to pass through, such as cloth bags, but not to particle components such as cement, most of the water in the injection phase is dehydrated into the surrounding ground, so it remains inside the bag. 71j material has a high concentration and has the advantage of increasing compressive strength due to the breathing phenomenon.The material of the bag body can be appropriately selected from the above examples, and as shown in Fig. It can also have a double structure with the water-permeable material 8b.

The injection material has a short gel time between trains, so the gel time is 5 to 2.
0 minutes is desirable, and the formulation is designed so that the compressive strength is 2 to 3 kg/n+,' 1 to 2 hours after breaking and pouring. Incidentally, a formulation example that meets these conditions is shown below.

1) Jet cement 200~J00 l'g/
~3 Ordinary cement 100~150kg/m1 Beatonite 20~6CJkg/n112) Denka ES 75~140kg/mrES setter 1.5~7 i<Q/ m' Bentonite 20~40kg/'Fly ash 10
0~150 kL/rN Ordinary cement 300~5
50kg/m33) Ordinary cement i 000~1
200kl? /mJRU' 150
~2oo+Kg7. rJR retarder, 9/r on 3-4
r? Bentonite 0-7 10 to 97 m, "[Effects of the Invention] As described below, the present invention is capable of fixing a bag body to a pipe body and reinforcing the railway ground with an N value of 4 or less, for example. Since the injection material is injected into the body, the tube body itself has the effect of acting as a support pile, and the expansion of the bag body has the effect of increasing the frictional resistance with the surrounding ground. 1. In other words, the train load is reduced by friction. The expanded bag body supports the pipe together with the pile as a pile.As a result, compared to simply driving only the pipe, the supporting effect is greater, so a shorter cylinder can be used, reducing the number of pipes used. The pipe body is not cheap9, but the construction efficiency (including the construction machine) is significantly improved.In addition, the bulging bag body not only increases the friction, but also has the effect of consolidating the surrounding ground, so it is even more effective. The ground is strengthened.Furthermore, there is no ground upheaval or blowout at the injection site, unlike in the chemical injection method.

Furthermore, since the pipe body is usually small in diameter and the injection work is simple, the fact that the work can be completed in a short time is particularly effective when this type of railway ground reinforcement is targeted. At the same time, I am completely satisfied with the safety aspect. In addition, since the installation of the pipe and the injection can be performed separately, it is possible to carry out construction work while waiting for a train to pass. A pile group effect can also be expected by constructing a large number of broken reinforced piles.

The size of the bag can be adjusted freely depending on the ground condition, injection pressure, etc.
I can make arrangements.

Furthermore, in the present invention, since the tubular body is installed by press-fitting, it is highly effective as a friction pile, and has a large supporting force compared to the supporting effect simply due to the expansion of the bag body. There is also an anchor effect due to the ballast cut 9.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of the construction state of the method of the present invention, FIG. 2 is a partially cutaway front view of the injection part, and FIG. 3 is a half-sectional front view of the fixed portion of the flexible bag. 1. Natural ground 2. Embankment 3. Roadbed ballast 4.
・Pipe body 5・・Balance cut 97・・Press fit 1” 8・・Flexible bag body Patent applicant: Japanese National Railways Light Kogyo Co., Ltd.

Claims (1)

[Claims] (1) A plurality of flexible sleeve-like bags are arranged in the axial direction on the outer wall of the tube, the upper and lower ends of each bag are fixed, and an injection port is formed on the outer wall of the tube corresponding to each bag. Furthermore, at the tip of the pipe body, prepare a cone-shaped 7 (with the lath cut facing forward) whose diameter is smaller than the outside diameter of the pipe body; directly into the target track ground without inserting the casing pipe. The bag is press-fitted to a predetermined depth, and then the injection material that is pumped from the base of the tube is injected from the injection port to inflate the bag body, and in this state, the injection material is hardened (10 bodies are created). A construction method for strengthening railway ground.