CN110055829B - Transient pore water pressure buffering method and device for railway subgrade - Google Patents
Transient pore water pressure buffering method and device for railway subgrade Download PDFInfo
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- CN110055829B CN110055829B CN201910394973.0A CN201910394973A CN110055829B CN 110055829 B CN110055829 B CN 110055829B CN 201910394973 A CN201910394973 A CN 201910394973A CN 110055829 B CN110055829 B CN 110055829B
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
- E01B1/00—Ballastway; Other means for supporting the sleepers or the track; Drainage of the ballastway
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Abstract
The invention provides a transient pore water pressure buffering method for a railway roadbed, wherein a buffering device is arranged in the roadbed, the dynamic effective stress of the roadbed is borne and transferred through a rigid device, and the dynamic pore water pressure of the roadbed is buffered through a flexible device. The buffering method can give consideration to two processes of transient pore water pressure increase and dissipation, and radically solves the problems of subgrade slurry turning and mud pumping. The invention also provides a buffer device which comprises a rigid device and a flexible device, wherein the rigid device is internally provided with an inner cavity, the surface of the rigid device is provided with a water through hole communicated with the inner cavity, pore water enters or flows out of the inner cavity through the water through hole, and the flexible device is arranged in the inner cavity to realize that the flexible device generates elastic deformation according to the change of the pore water pressure. The buffering device guarantees the stability of the roadbed through the rigid device, the dynamic pore water pressure of the roadbed is buffered through the flexible device, and the flexible device is arranged in the inner cavity of the rigid device and can play a role in protecting the flexible device.
Description
Technical Field
The invention relates to the technical field of railway subgrades, in particular to a transient pore water pressure buffering method and device for a railway subgrade.
Background
Aiming at the transient pore water pressure of the railway subgrade, the traditional treatment method mainly takes prevention and control as the main part, namely the transient pore water pressure of the subgrade is reduced by strengthening the drainage and water isolation of the subgrade water, and the concrete measures mainly comprise: on one hand, the permeability inside the roadbed is improved, and the water discharge rate inside the roadbed is accelerated; on the other hand, grouting is performed in a roadbed damaged area to block rainwater infiltration, for example, chinese patent CN201710351724 discloses a renovation method for treating slab ballastless track railway roadbed grout pumping, which prevents water infiltration into a foundation bed through grouting to block rainwater infiltration.
The traditional method for treating transient pore water pressure of railway subgrade belongs to a passive treatment method, has higher requirements on treatment materials and procedures, and has the following defects in many aspects:
firstly, in drainage treatment, the foundation bed must be mechanically tamped during construction to ensure higher stability, so the whole porosity ratio of the foundation bed is small, and the permeability of the foundation bed is poor. In continuous rainfall weather or local heavy rainfall, the moisture in the foundation bed is difficult to discharge in time.
Secondly, in the water-resisting treatment, the modes of grouting and the like are adopted, dynamic pore water cannot pass through a grouting area, but dynamic pressure still exists and can be transmitted to a far area, so that the grouting area must be large enough and grouting is uniform, and the treatment requirement can be met. Secondly, the grouting layer has good waterproofness, and on one hand, the grouting layer overcomes the circulating extrusion and suction effects of dynamic pore water pressure; on the other hand, the circulation effective stress action of the soil framework is born, so that the requirement on the grouting material is high, and the long-term strength of the grouting material is difficult to ensure. Once a certain area of the grouting layer is damaged, the damage gradually spreads to other areas under the action of dynamic pore water pressure.
In view of the above, a method and a device for transient pore water pressure buffering of a railway roadbed are urgently needed to solve the problems in the prior art.
Disclosure of Invention
The invention aims to provide a transient pore water pressure buffering method for a railway roadbed, which has the following specific technical scheme:
a transient pore water pressure buffering method for a railway subgrade comprises a buffering device, wherein the buffering device comprises a rigid device and a flexible device, a cavity structure is arranged in the rigid device, at least one water through hole communicated with an inner cavity is formed in the surface of the rigid device, and the flexible device is integrally arranged in the inner cavity of the rigid device;
the buffering method comprises the steps that the buffering device is arranged in a roadbed, dynamic effective stress of the roadbed is borne and transmitted through a rigid device, and dynamic pore water pressure of the roadbed is buffered through a flexible device.
Preferably, in the above technical solution, the number of the buffer devices is at least one, and a plurality of the buffer devices are uniformly arranged on the surface layer of the foundation bed of the roadbed at intervals and are filled with the sandstone layer.
Preferably, in the above technical scheme, when a train comes, the roadbed soil framework is dynamically loaded by the train, the volume of the loaded position of the roadbed is rapidly reduced, and dynamic pore water enters the inner cavity of the rigid device through the water through holes, so that the flexible device is deformed, the dynamic pore water pressure is weakened, and the purpose of relieving the excess pore water pressure is achieved;
when the train leaves, the roadbed soil framework unloads the dynamic load of the train, the volume of the position of the roadbed unloading load is rapidly increased, and negative pore water pressure is formed; under the action of negative gap water pressure, pore water in the inner cavity of the rigid device is sucked out, the purpose of relieving the negative pore water pressure is achieved, and the flexible device recovers deformation and is ready for next dynamic load action.
The invention also provides a transient pore water pressure buffering device for the railway roadbed, which comprises a rigid device for bearing and transmitting dynamic effective stress of the roadbed and a flexible device for buffering the dynamic pore water pressure of the roadbed, wherein a cavity structure is arranged in the rigid device, at least one water passing hole communicated with the inner cavity is arranged on the surface of the rigid device, pore water flows into or flows out of the inner cavity through the water passing hole, the flexible device is integrally arranged in the inner cavity of the rigid device, and the flexible device is elastically deformed under the action of the pore water pressure.
Preferably, in the above technical solution, the rigid device is a hollow spherical shell, and the flexible device is a hollow rubber balloon.
Preferably, in the above technical solution, the water holes are uniformly distributed on the surface of the spherical shell.
In the above technical scheme, preferably, the outer diameter of the spherical shell is 6-8cm, the thickness of the shell is 8-10mm, and the diameter of the water through hole is 4-5 mm.
In the above technical solution, preferably, the air pressure inside the hollow rubber balloon is 15 to 20 kPa.
In the above technical solution, preferably, the spherical shell is made of low carbon stainless steel or hard plastic.
The technical scheme of the invention has the following beneficial effects:
(1) aiming at the transient pore water pressure of the railway subgrade, the prior invention achievements belong to passive prevention and control measures, mainly isolate and dredge subgrade water, and the treatment effect of the invention has a larger relation with the actual water content of the subgrade. The transient pore water pressure buffering method for the railway subgrade, provided by the invention, jumps out of the constraint of subgrade water, and is a new thinking mode; the phenomenon of slurry dumping and mud pumping of the railway subgrade is treated by arranging the buffer device; the dynamic effective stress of the roadbed is borne and transmitted through the rigid device, the overall stability of the roadbed is ensured, the dynamic pore water pressure of the roadbed is buffered through the flexible device, the effect of weakening the pore water pressure is achieved, the slurry turning and mud pumping are solved from the source, and the buffering method is not influenced by the water content of the roadbed, so that the slurry turning and mud pumping can be avoided no matter continuous rainfall or strong rainfall.
(2) The buffer method can give consideration to two processes of transient pore water pressure increase and dissipation, when the pore water pressure increases, pore water and a small amount of fine soil particles enter the rigid device, and the pore water pressure is weakened through the flexible device, so that the aim of relieving the excess pore water pressure is fulfilled; when the pore water pressure is dissipated, under the action of negative pore water pressure, pore water in the rigid device and a small amount of attached fine soil particles can be quickly sucked out, so that the purpose of relieving the negative pore water pressure is achieved, and meanwhile, the flexible device is restored to the original state to prepare for next buffering.
(3) According to the buffering method, the sandstone layers are filled around the plurality of buffering devices, the number of the buffering devices can be set according to actual conditions (such as the precipitation amount of the area), the buffering devices and the sandstone layers can form a buffering network, all buffering points are coordinated with each other, the impact force caused by the dynamic load of the train is distributed, the buffering capacity is high, and the omnibearing buffering can be realized.
(4) The buffer device comprises a rigid device for bearing and transmitting dynamic effective stress of a roadbed and a flexible device for buffering dynamic pore water pressure of the roadbed, wherein an inner cavity is arranged in the rigid device, a water through hole communicated with the inner cavity is formed in the surface of the rigid device, pore water flows into or flows out of the inner cavity through the water through hole, and the flexible device is arranged in the inner cavity and elastically deforms according to the change of the pore water pressure; the flexible device is arranged in the rigid device, so that the flexible device can be well protected, the front impact of the soil framework on the flexible device can be avoided, and the service life of the flexible device is prolonged.
(5) The buffer device has the advantages of simple structure, easily obtained materials, easy processing and batch production, similar construction process to that of the common roadbed construction and smaller engineering construction difficulty.
(6) The spherical shell of the buffer device adopts low-carbon stainless steel or hard plastic, has higher strength and rigidity and better corrosion resistance, and effectively ensures the service life of the buffer device.
(7) The internal air pressure of the hollow rubber balloon is 15-20kPa, the air pressure value is the static pore water pressure of the depth of the buffer device in the roadbed saturation state, the air pressure value can be set to well ensure the working stability of the hollow rubber balloon, ensure that the hollow rubber balloon deforms in time to relieve the pore water pressure when being extruded by the pore water, and simultaneously ensure that the hollow rubber balloon is not broken due to extrusion.
(8) The spherical shell has the outer diameter of 6-8cm, the shell thickness of 8-10mm and the water through hole diameter of 4-5mm, is small and exquisite, is easy to process and convenient to use in roadbed construction, can ensure that pore water enters and flows out of the rigid device when the water through hole diameter is 4-5mm, and simultaneously prevents large-particle gravels from entering the rigid device to cause the abnormal elastic deformation of the flexible device, thereby influencing the efficacy of the buffer device.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic view of the overall structure of the cushioning device of the present invention;
FIG. 2 is a schematic view of the damper of FIG. 1 with a partial spherical housing removed;
FIG. 3 is a schematic view of a damper apparatus according to the present invention;
the track comprises a rail 1, a rail 2, a sleeper 3, a ballast 4, a first gravel layer 5, a second gravel layer 6, a third gravel layer 7, a buffer device 7.1, a spherical shell 7.2, a water through hole 7.3, a hollow rubber balloon 8 and a foundation bed.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Example 1:
referring to fig. 1-2, a transient pore water pressure buffering device for a railway roadbed comprises a rigid device for bearing and transmitting dynamic effective stress of the roadbed and a flexible device for buffering dynamic pore water pressure of the roadbed, wherein a cavity structure is arranged in the rigid device, at least one water passing hole communicated with an inner cavity is arranged on the surface of the rigid device (the cavity structure is an inner cavity), pore water flows into or out of the inner cavity through the water passing hole, the flexible device is integrally arranged in the inner cavity of the rigid device, and the flexible device is elastically deformed under the action of the pore water pressure. Namely, the flexible device deforms when the pore water pressure is greater than the deformation pressure value of the flexible device, and the flexible device recovers to the original state when the pore water pressure is less than the deformation pressure value of the flexible device.
The rigid device is a hollow spherical shell 7.1, the flexible device is a hollow rubber balloon 7.3 (preferably, the hollow rubber balloon is a rubber balloon in the prior art), and a solid rubber balloon can be adopted, so that the deformation requirement can be met. The water holes 7.2 are uniformly distributed on the surface of the spherical shell 7.1. The outer diameter of the spherical shell is 6-8cm, the thickness of the shell is 8-10mm, and the diameter of the water through hole is 4-5 mm. The internal air pressure of the hollow rubber balloon 7.3 is 15-20kPa, and the internal air pressure is the air pressure when the hollow rubber balloon does not work. Preferably, the outer diameter of the spherical shell in the embodiment is 6cm, the thickness of the shell is 8mm, the diameter of the water through hole is 4mm, and the air pressure of the hollow rubber balloon is 15 kPa.
When the pressure generated by the pore water is greater than the air pressure in the hollow rubber balloon, the pore water pressure extrudes the hollow rubber balloon to deform, so that the pore water pressure is weakened, and the aim of relieving the excess pore water pressure is fulfilled; when the pore water pressure is smaller than the air pressure in the hollow rubber balloon, the hollow rubber balloon is restored to the original state.
Preferably, the spherical shell is made of low-carbon stainless steel or hard plastic, and has high strength, rigidity and corrosion resistance; the hollow rubber balloon has good elasticity, wear resistance and corrosion resistance.
Referring to fig. 3, the present embodiment specifically describes an application of the buffering device of the present invention by taking a ballast railway as an example.
The buffer device is arranged in the roadbed, the roadbed dynamic effective stress is borne and transferred through the rigid device, and the roadbed dynamic pore water pressure is buffered through the flexible device.
The number of the buffer devices is at least one, and a plurality of buffer devices are uniformly arranged on the surface layer of the foundation bed of the roadbed at intervals and are filled with a sandstone layer (namely, the sandstone is filled around the buffer devices).
The sandstone layers comprise a first sandstone layer 4, a second sandstone layer 5 and a third sandstone layer 6; uniformly paving the sand and stone filler with better gradation and the particle size of 1-20mm on the surface of the foundation bed 8 to form a first sand and stone layer 4 with the thickness of 5-6cm, uniformly arranging the buffer device on the surface of the first sand and stone layer 4, then filling the sand and stone filler with the better gradation and the particle size of 1-20mm around the buffer device to form a second sand and stone layer 5 with the thickness of 6-8cm, and finally uniformly paving the sand and stone filler with the better gradation and the particle size of 1-20mm on the second sand and stone layer 5 and the buffer device to form a third sand and stone layer 6 with the thickness of 5-6 cm. And finally, paving the railway ballast 3, the sleeper 2 and the railway track 1 on the surface of the third sand-stone layer 6 in sequence.
When a train comes, the roadbed soil framework is dynamically loaded by the train, the volume of the loaded position of the roadbed is rapidly reduced, dynamic pore water and a small amount of attached fine soil particles enter the inner cavity of the rigid device (namely the spherical shell) through the water through holes, so that the flexible device (namely the hollow rubber balloon) is deformed, the dynamic pore water pressure is weakened, and the purpose of relieving the excess pore water pressure is achieved;
when the train leaves, the roadbed soil framework unloads the dynamic load of the train, the volume of the position of the roadbed unloading load is rapidly increased, and negative pore water pressure is formed; under the action of negative void water pressure, the void water in the inner cavity of the rigid device and a small amount of attached fine soil particles are sucked out, the purpose of relieving the negative void water pressure is achieved, and the flexible device recovers deformation and is ready for next dynamic load action.
By applying the technical scheme of the invention, the effects are as follows:
the buffering device ensures the stability of the roadbed through the rigid device, realizes the buffering of the dynamic pore water pressure of the roadbed through the flexible device, and can protect the flexible device by arranging the flexible device in the inner cavity of the rigid device, thereby avoiding the front impact of the soil framework on the flexible device and prolonging the service life of the flexible device.
The buffering method can give consideration to two processes of transient pore water pressure increase and dissipation, radically solves the problem of subgrade slurry overflow and mud pumping, is not influenced by the water content of the subgrade, and has high practicability.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. The transient pore water pressure buffering method for the railway subgrade is characterized by comprising a buffering device, wherein the buffering device comprises a rigid device and a flexible device, a cavity structure is arranged in the rigid device, at least one water passing hole communicated with an inner cavity is formed in the surface of the rigid device, and the flexible device is integrally arranged in the inner cavity of the rigid device;
the buffering method comprises the steps that the buffering device is arranged in a roadbed, the rigid device bears and transfers dynamic effective stress of the roadbed, and the flexible device buffers dynamic pore water pressure of the roadbed;
when a train comes, the roadbed soil framework is dynamically loaded by the train, the volume of the loaded position of the roadbed is rapidly reduced, and dynamic pore water enters the inner cavity of the rigid device through the water through holes, so that the flexible device is deformed, the dynamic pore water pressure is weakened, and the purpose of relieving the excess pore water pressure is achieved;
when the train leaves, the roadbed soil framework unloads the dynamic load of the train, the volume of the position of the roadbed unloading load is rapidly increased, and negative pore water pressure is formed; under the action of negative gap water pressure, pore water in the inner cavity of the rigid device is sucked out, the purpose of relieving the negative pore water pressure is achieved, and the flexible device recovers deformation and is ready for next dynamic load action.
2. The transient pore water pressure buffering method for railway subgrade as claimed in claim 1, wherein the number of said buffering devices is at least one, and a plurality of said buffering devices are uniformly arranged on the surface layer of the subgrade bed at intervals and are filled with a sandstone layer.
3. The utility model provides a railway roadbed transient state pore water pressure buffer, its characterized in that, including the rigidity device that is used for bearing and transmits roadbed developments effective stress and the flexible mounting who is used for buffering roadbed developments pore water pressure, the inside of rigidity device is equipped with cavity structures and is equipped with on the surface and crosses the water hole with at least one of inner chamber intercommunication, realizes through crossing the water hole that pore water flows in or flows the inner chamber, the flexible mounting whole set up in the inner chamber of rigidity device just the flexible mounting receives pore water pressure and takes place elastic deformation.
4. The transient pore water pressure buffering device of railway subgrade as claimed in claim 3, characterized in that said rigid device is a hollow spherical shell (7.1) and said flexible device is a hollow rubber balloon (7.3).
5. The transient pore water pressure buffering device for railway subgrade as claimed in claim 4, characterized in that the water through holes (7.2) are uniformly distributed on the surface of the spherical shell (7.1).
6. The transient pore water pressure buffering device for railway subgrade as claimed in claim 5, wherein the outer diameter of the spherical shell is 6-8cm, the thickness of the shell is 8-10mm, and the diameter of the water through hole is 4-5 mm.
7. The transient pore water pressure buffering device for railway subgrade as claimed in claim 4, wherein the air pressure inside the hollow rubber balloon (7.3) is 15-20 kPa.
8. The transient pore water pressure buffering device for railway subgrade as claimed in any one of claims 4-7, wherein the spherical shell is made of low carbon stainless steel or hard plastic.
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| CN201910394973.0A CN110055829B (en) | 2019-05-13 | 2019-05-13 | Transient pore water pressure buffering method and device for railway subgrade |
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| CN201910394973.0A CN110055829B (en) | 2019-05-13 | 2019-05-13 | Transient pore water pressure buffering method and device for railway subgrade |
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| CN110055829A CN110055829A (en) | 2019-07-26 |
| CN110055829B true CN110055829B (en) | 2020-03-10 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| EP0124500A2 (en) * | 1983-03-31 | 1984-11-07 | Monsanto Company | Elongated bendable drainage mat |
| JP2531574B2 (en) * | 1993-12-07 | 1996-09-04 | 日本鉄道建設公団 | Projection support method for slab track |
| CN1296560C (en) * | 2002-10-01 | 2007-01-24 | 沃尔夫冈·马库斯 | Fixed track for rail vehicles and method for production thereof |
| JP2011144514A (en) * | 2010-01-12 | 2011-07-28 | Railway Technical Research Institute | Airtight bag banking |
| CN108131162A (en) * | 2018-02-11 | 2018-06-08 | 中铁二院工程集团有限责任公司 | A kind of tunnel drainage device and tunnel solid concrete roabed |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10344433B2 (en) * | 2016-03-31 | 2019-07-09 | Tbt Engineering Limited | Subgrade peat stabilisation system for railway |
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2019
- 2019-05-13 CN CN201910394973.0A patent/CN110055829B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0124500A2 (en) * | 1983-03-31 | 1984-11-07 | Monsanto Company | Elongated bendable drainage mat |
| JP2531574B2 (en) * | 1993-12-07 | 1996-09-04 | 日本鉄道建設公団 | Projection support method for slab track |
| CN1296560C (en) * | 2002-10-01 | 2007-01-24 | 沃尔夫冈·马库斯 | Fixed track for rail vehicles and method for production thereof |
| JP2011144514A (en) * | 2010-01-12 | 2011-07-28 | Railway Technical Research Institute | Airtight bag banking |
| CN108131162A (en) * | 2018-02-11 | 2018-06-08 | 中铁二院工程集团有限责任公司 | A kind of tunnel drainage device and tunnel solid concrete roabed |
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