Fault zone dislocation non-uniform deformation isolation structure

Abstract

The invention belongs to the technical field of railway roadbeds, and discloses a fault zone dislocation non-uniform deformation isolation structure which is fully paved between a subgrade bed bottom layer and an embankment below a subgrade bed and between a subgrade bed surface layer and the subgrade bed bottom layer respectively and arranged along the trend direction of a line. The fault zone dislocation non-uniform deformation isolation structure comprises a plurality of rubber cushion layers (1), closed sliding rails (2) and splicing seams (3), wherein the closed sliding rails (2) and the splicing seams (3) are used for connecting the rubber cushion layers (1). Wherein dotted bulges (4) are arranged on the upper surface and the lower surface of each rubber cushion layer (1); the trend of the closed sliding rails (2) is parallel to the trend of a fault zone, the trend of the splicing seams (3) is perpendicular to the trend of the fault zone, and the rubber cushion layers (1) are connected through the closed sliding rails (2) and the splicing seams (3) to form an integral isolation structure.

Description

Technical Field

[0001] The invention belongs to the technical field of railway roadbed, and in particular relates to a fault zone dislocation uneven deformation isolation structure. Background Art

[0002] my country's railway development faces a new challenge: filling gaps in western railways, constructing multi-directional access routes into Tibet, and improving outbound routes from Xinjiang. Generally speaking, given the negative impact of active fault zones, active fault zones have often been avoided during railway line selection. However, with the increasing density of my country's railway network and the urgent need to build railways in the difficult mountainous areas of the southwest and northwest, some new railway lines will inevitably cross active fault zones. The strong seismic effects of rapid stick-slip movement in fault zones, the surface rupture effects of strong earthquakes, and the long-term creep and slip movement between earthquakes are significant, posing significant challenges to the construction and subsequent operation of near-fault railway subgrades. There is an urgent need to develop new measures to control the uneven deformation of fault zone movement.

[0003] In the existing technology, the commonly used measures to control the deformation of the fault zone dislocation roadbed mainly include geogrids, pile-board structures, etc. Figure 1 As shown in the figure, geogrids have high damping, large elastic modulus and excellent flexibility. Through the interlocking and friction between the grid and the roadbed filler, the toughness and stability of the roadbed structure are significantly enhanced. Figure 2 The pile-sheet structure shown has strong rigidity. These two measures enable the roadbed to have the ability to resist the displacement and deformation of the fault zone to a certain extent.

[0004] The existing technical solutions have the following technical defects:

[0005] 1. The existing roadbed reinforcement measures need to improve their ability to resist deformation and vibration reduction.

[0006] Fault zones are the root cause of earthquakes. Their violent stick-slip motion not only generates seismic waves but can also trigger surface ruptures, releasing enormous amounts of energy. Commonly used roadbed pile-slab structures are rigid and cannot absorb fault zone motion and seismic energy through their own deformation. When the amount of stick-slip motion in the fault zone is small and the earthquake magnitude is low, the structure can still withstand it. However, if a strong near-fault earthquake and large-scale surface rupture occur, the rigid structure is prone to brittle failure, threatening the operational safety of the railway subgrade. Long-term inter-seismic creep in the fault zone causes continuous accumulation of structural stress, which is also detrimental to its durability. While geogrids offer good flexibility and enhance the integrity of the subgrade, their deformation control concept still relies on directly resisting fault zone motion, failing to effectively mitigate the damage posed to the subgrade by violent stick-slip motion in the fault zone.

[0007] 2. Existing roadbed lacks deformation self-recovery ability

[0008] Traditional railway subgrades are rigorously compacted using heavy machinery, resulting in excellent compressive resistance but relatively weak tensile and shear resistance. When a fault zone shifts, the subgrade filler near the fault primarily disperses stress through crushing and rearrangement. While capable of self-adapting to deformation, elastic deformation accounts for a small proportion, making it prone to irreversible tensile and shear plastic deformation. This can lead to cracks, collapses, bulges, and other defects that are unable to repair themselves, causing irreversible damage to the subgrade structure and making it impossible to effectively control the uneven deformation of the fault zone.

[0009] In summary, geogrids and pile-sheet structures are currently commonly used in roadbed engineering projects both domestically and internationally to mitigate displacement. However, these structures have limited capacity to resist deformation caused by fault zone displacement, making it difficult to effectively prevent damage to the roadbed caused by displacement of deep and active fault zones in the challenging western mountainous areas. Furthermore, strong near-fault earthquakes generated during stick-slip displacement in fault zones exhibit prominent directional effects, large vertical components, and pronounced pulse characteristics, necessitating a lack of shock absorption and energy dissipation measures in conventional roadbeds. Therefore, establishing an isolation structure for uneven deformation during fault zone displacement would provide technical support for controlling near-fault roadbed deformation and would be of great practical significance for near-fault railways currently under construction and planned. Summary of the Invention

[0010] In light of this, the present invention provides an isolation structure for uneven deformation of fault zone dislocations in railway subgrades. Designed in accordance with the "Code for Geotechnical Engineering Investigation (GB50021-2001) (2009 edition)", compared to traditional fault zone dislocation and deformation control measures, the present invention's fault zone deformation isolation structure is suitable for situations where railways cross strongly newly active faults (average activity rate >1mm / year, historical earthquake magnitude ≥7). It avoids concentrated damage to the subgrade, exhibits excellent deformation adaptability, and mitigates the impact of fault zone dislocations on line smoothness. Furthermore, the isolation structure possesses excellent elasticity and energy absorption properties, capable of absorbing the impact energy generated by stick-slip dislocations in the fault zone, correcting uneven deformation caused by the dislocations, and preventing deformation and energy from being transferred to the subgrade surface.

[0011] To achieve the above-mentioned object, the present invention adopts the following technical solution: a fault zone dislocation and uneven deformation isolation structure; the fault zone dislocation and uneven deformation isolation structure is fully laid between the subgrade bottom layer and the embankment below the subgrade, and between the subgrade surface layer and the subgrade bottom layer, and is arranged along the direction of the railway subgrade;

[0012] The fault zone dislocation uneven deformation isolation structure includes:

[0013] A plurality of rubber pad layers (1) and a closed slide rail (2) and a joint seam (3) for connecting the plurality of rubber pad layers (1); wherein:

[0014] Each of the rubber pad layers (1) is provided with dot-shaped protrusions (4) on its upper and lower surfaces;

[0015] The closed slide rail (2) and the joint seam (3) are arranged between each rubber pad layer (1); the direction of the closed slide rail (2) is parallel to the direction of the fracture zone, and the direction of the joint seam (3) is perpendicular to the direction of the fracture zone. Each rubber pad layer (1) is connected to form an integral isolation structure through the closed slide rail (2) and the joint seam (3).

[0016] Preferably, the dot-shaped protrusions are rubber dot-shaped protrusions.

[0017] Preferably, the isolation structure is arranged in blocks by using a plurality of rubber pad layers (1), and the isolation structure is cut into blocks every 3 to 5 m along the direction of the fault zone and perpendicular to the direction of the fault zone.

[0018] Preferably, the closed slide rail (2) has a width of 5 cm.

[0019] Preferably, a groove is formed between each of the dot-shaped protrusions (4), and a plurality of water-permeable holes (5) are arranged on the groove at a certain interval.

[0020] Preferably, the spacing is set at equal intervals or non-equal intervals.

[0021] Preferably, based on the angle between the line direction and the fault zone direction, the width of the surface rupture caused by the historical stick-slip movement of the fault zone and the scope of influence of the surface rupture effect of strong earthquakes are comprehensively considered to determine the laying range of the fault zone dislocation uneven deformation isolation structure along the line direction.

[0022] Preferably, the closed slide rail (2) is composed of a housing (6), a rotating shaft (7), a spherical ball (8), a baffle (9), a sealing ring (10), an anti-pullout bolt (11), a connecting bolt (12), a connecting plate (13), and a connecting pad (14), and is used to connect two adjacent rubber pad layers (1) and ensure that the two adjacent rubber pad layers (1) can only move horizontally relative to each other along the direction of the fracture zone or rotate axially around the closed slide rail (2). The horizontal movable distance of the closed slide rail (2) is determined based on the creep slip of the fracture zone of the railway roadbed within a hundred-year service life; the spherical ball (8) is located between the housing (6) and the rotating shaft (7) and is used to reduce the friction force of the closed slide rail (2) during axial movement and radial rotation; the anti-pullout bolt (11) is inserted into the baffle (9) to fix the baffle (9) on the housing (6) and is used to limit excessive horizontal relative displacement between two adjacent rubber pad layers (1); the sealing ring (10) is located between the rotating shaft (7) and the baffle (9) and is used to prevent roadbed filler particles from invading the interior of the closed slide rail (2) and hindering the movement of the mechanism.

[0023] Working principle:

[0024] (1) The closed slide rail 2 is a flexible structure. When the strike-slip fault slowly creeps and dislocates, the roadbed as a whole exhibits an S-shaped lateral displacement in the horizontal direction. Due to the presence of the closed slide rail 2, each rubber pad 1 can independently undergo relative displacement along the fault zone or rotate around the closed slide rail 2 axially, increasing the overall flexibility of the roadbed structure and the continuity of the isolation structure, avoiding concentrated damage to the roadbed at a certain location, and improving the overall stress condition of the roadbed.

[0025] (2) The rubber cushion layer 1 has the ability to self-recover from deformation. During the movement of the fault zone, the roadbed filler particles drive the rubber cushion layer 1 to undergo horizontal shear deformation. After deformation, the rubber cushion layer 1 will gradually recover its original shape, blocking the uneven deformation from being transmitted to the top surface of the roadbed, thereby avoiding damage to the upper roadbed structure of the rubber cushion layer 1.

[0026] (3) When the strike-slip fault rapidly slips, the rubber pad 1 can produce elastic compression deformation and absorb part of the earthquake energy.

[0027] (4) The baffle 9 and anti-pullout bolts 11 in the closed slide rail 2 are rigid structures that limit excessive horizontal relative displacement between the rubber pads 1 and protect the railway line from drastic changes. If a major earthquake occurs, the stick-slip displacement of the fault zone is large, and the anti-pullout bolts 11 are unable to resist the displacement deformation, the anti-pullout bolts will be pulled off, and the baffle will fall off from the housing 6, thereby consuming the displacement energy of the fault zone and reducing the damage caused by the fault zone movement to the roadbed.

[0028] Beneficial effects of the present invention:

[0029] (1) This invention proposes a new concept and method for controlling deformation of near-fault railway subgrades, which no longer relies solely on rigid structures to resist the deformation of the fault zone. Based on the design concept of combining rigidity and flexibility, multiple low-resistance closed slide rails parallel to the direction of the fault zone are used to increase the overall flexibility of the subgrade structure, control the location and range of uneven deformation and damage of the subgrade, reduce the degree of subgrade damage, and improve the overall stress condition of the subgrade. When the deformation of the fault zone is large, the pull-out bolts in the closed slide rails can resist and dissipate the stick-slip dislocation energy of the fault zone. In addition, the rubber cushion layer gives the granular subgrade the ability to self-recover from deformation.

[0030] (2) The present invention reduces the damage caused by earthquake vibrations to the roadbed. The rubber cushion layer deforms itself, absorbing the impact energy of earthquake vibrations, thus giving the roadbed the ability to absorb shock and dissipate energy.

[0031] (3) The present invention can solve the problem of insufficient deformation control capability of existing near-fault roadbed projects and proposes a new concept for deformation control of near-fault roadbeds. It combines an elastic rubber cushion with deformation self-recovery capability with a low-resistance closed slide rail, thereby enhancing the adaptability of the roadbed to the slow creep and rapid stick-slip deformation of the fault zone.

[0032] (4) The present invention provides a new type of fault zone dislocation and uneven deformation isolation structure, which provides a new means for controlling the deformation of railway subgrade near faults in the difficult mountainous areas of western my country. It can be widely promoted in the railway and even highway industries to improve the level of subgrade design and construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of geogrid structure according to prior art;

[0034] Figure 2 A schematic diagram of a pile-plate structure according to the prior art;

[0035] Figure 3 A schematic diagram of the location of a fault zone dislocation and uneven deformation isolation structure according to an embodiment of the present invention;

[0036] Figure 4 A top view of the overall structure of the fault zone dislocation and uneven deformation isolation structure according to an embodiment of the present invention;

[0037] Figure 5 is a structural diagram of the rubber cushion layer of the present invention according to an embodiment of the present invention;

[0038] FIG6 is a structural diagram of a closed slide rail according to an embodiment of the present invention; FIG6(a) is a three-dimensional structural diagram, FIG6(b) is a cross-sectional diagram, and FIG6(c) is a longitudinal cross-sectional diagram. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] This embodiment provides a fault zone dislocation uneven deformation isolation structure; Figure 3 As shown, the fault zone dislocation uneven deformation isolation structure is fully laid between the base bed bottom layer and the embankment below the base bed, and between the base bed surface layer and the base bed bottom layer, and is arranged along the strike direction of the railway subgrade;

[0041] like Figure 4As shown, the fault zone dislocation uneven deformation isolation structure includes:

[0042] Multiple rubber pads 1 and closed slide rails 2 and joints 3 for connecting the multiple rubber pads 1; wherein:

[0043] like Figure 5 As shown, each of the rubber pad layers 1 is provided with dot-shaped protrusions 4 on the upper and lower surfaces;

[0044] The closed slide rail 2 and the joint seam 3 are arranged between each rubber pad layer 1. The direction of the closed slide rail 2 is parallel to the direction of the fracture zone, and the direction of the joint seam 3 is perpendicular to the direction of the fracture zone.

[0045] In this embodiment, the dot-shaped protrusions are rubber dot-shaped protrusions, which can better adapt to elastic deformation, absorb earthquake energy, and embed the isolation structure and the roadbed filler together.

[0046] As a preferred embodiment, the isolation structure is divided into blocks using multiple rubber pads 1. In this embodiment, utilizing the principle of truncation design, the isolation structure is divided into blocks every 3-5 meters along and perpendicular to the fault zone. Enclosed rails 2 and joints 3 are provided between each rubber pad 1. The 5 cm wide closed rails 2 connect the rubber pads 1 to form a single, integrated isolation structure.

[0047] As a preferred embodiment, a groove is formed between each of the dot-shaped protrusions 4, and a plurality of water-permeable holes 5 are provided in the groove at a predetermined interval to facilitate drainage of the railway subgrade. The spacing can be equal or unequal, depending on the laying conditions of the railway subgrade and historical rainfall, and is within the scope of protection of the present invention.

[0048] As a preferred embodiment, the dot-shaped protrusions are made of rubber.

[0049] As a preferred embodiment, based on the angle between the line direction and the fault zone direction, the width of the surface rupture caused by the historical stick-slip movement of the fault zone and the scope of influence of the surface rupture effect of strong earthquakes are comprehensively considered to determine the laying range of the fault zone uneven deformation isolation structure along the line direction.

[0050] As a preferred embodiment, as shown in Figures 6(a), 6(b) and 6(c), the closed slide rail (2) is composed of a housing 6, a rotating shaft 7, a spherical ball 8, a baffle 9, a sealing ring 10, an anti-pullout bolt 11, a connecting bolt 12, a connecting plate 13, and a connecting pad 14, which is used to connect two adjacent rubber pads 1 and ensure that the two adjacent rubber pads 1 can only move horizontally relative to each other along the direction of the fracture zone or rotate axially around the closed slide rail 2. The horizontal movable distance of the closed slide rail 2 is determined based on the creep displacement of the fracture zone within the 100-year service life of the railway subgrade; the spherical ball 8 is located between the outer shell 6 and the rotating shaft 7, and is used to reduce the friction force of the closed slide rail 2 during axial movement and radial rotation; the anti-pullout bolt 11 is inserted into the baffle 9 to fix the baffle 9 on the outer shell 6, and is used to limit the excessive horizontal relative displacement between two adjacent rubber pad layers 1; the sealing ring 10 is located between the rotating shaft 7 and the baffle 9, and is used to prevent subgrade filler particles from invading the interior of the closed slide rail 2 and hindering the movement of the mechanism.

[0051] Working principle:

[0052] (1) The closed slide rail 2 is a flexible structure. When the strike-slip fault slowly creeps and dislocates, the roadbed as a whole exhibits an S-shaped lateral displacement in the horizontal direction. Due to the presence of the closed slide rail 2, each rubber pad 1 can independently undergo relative displacement along the fault zone or rotate around the closed slide rail 2 axially, increasing the overall flexibility of the roadbed structure and the continuity of the isolation structure, avoiding concentrated damage to the roadbed at a certain location, and improving the overall stress condition of the roadbed.

[0053] (2) The rubber cushion layer 1 has the ability to self-recover from deformation. During the movement of the fault zone, the roadbed filler particles drive the rubber cushion layer 1 to undergo horizontal shear deformation. After deformation, the rubber cushion layer 1 will gradually recover its original shape, blocking the uneven deformation from being transmitted to the top surface of the roadbed, thereby avoiding damage to the upper roadbed structure of the rubber cushion layer 1.

[0054] (3) When the strike-slip fault rapidly slips, the rubber pad 1 can produce elastic compression deformation and absorb part of the earthquake energy.

[0055] (4) The baffle 9 and anti-pullout bolts 11 in the closed slide rail 2 are rigid structures that limit excessive horizontal relative displacement between the rubber pads 1 and protect the railway line from drastic changes. If a major earthquake occurs, the stick-slip displacement of the fault zone is large, and the anti-pullout bolts 11 are unable to resist the displacement deformation, the anti-pullout bolts will be pulled off, and the baffle will fall off from the housing 6, thereby consuming the displacement energy of the fault zone and reducing the damage caused by the fault zone movement to the roadbed.

[0056] As for the devices and methods of use disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the methods.

[0057] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fault zone dislocation and uneven deformation isolation structure, characterized in that: The fault zone dislocation uneven deformation isolation structure is fully laid between the base bed bottom layer and the embankment below the base bed, and between the base bed surface layer and the base bed bottom layer, and is arranged along the strike direction of the railway subgrade; The fault zone dislocation uneven deformation isolation structure includes: A plurality of rubber pad layers (1) and a closed slide rail (2) and a joint seam (3) for connecting the plurality of rubber pad layers (1); wherein: Each of the rubber pad layers (1) is provided with dot-shaped protrusions (4) on its upper and lower surfaces; The closed slide rail (2) and the joint seam (3) are arranged between each rubber pad layer (1); the direction of the closed slide rail (2) is parallel to the direction of the fracture zone, and the direction of the joint seam (3) is perpendicular to the direction of the fracture zone. Each rubber pad layer (1) is connected to form an integral isolation structure through the closed slide rail (2) and the joint seam (3).

2. The fault zone dislocation and uneven deformation isolation structure according to claim 1, characterized in that: The dot-shaped protrusions are rubber dot-shaped protrusions.

3. The fault zone dislocation and uneven deformation isolation structure according to claim 2, characterized in that: The isolation structure is arranged in blocks through a plurality of rubber pad layers (1), and the isolation structure is cut into blocks every 3 to 5 m along the direction of the fault zone and perpendicular to the direction of the fault zone.

4. The fault zone dislocation and uneven deformation isolation structure according to claim 3, characterized in that: The width of the closed slide rail (2) is 5 cm.

5. The fault zone dislocation and uneven deformation isolation structure according to claim 4, characterized in that: A groove is formed between each of the dot-shaped protrusions (4), and a plurality of water-permeable holes (5) are arranged on the groove at a certain interval.

6. The fault zone dislocation and uneven deformation isolation structure according to claim 5, characterized in that: The spacing is set at equal intervals or at non-equal intervals.

7. The fault zone dislocation and uneven deformation isolation structure according to claim 6, characterized in that: Based on the angle between the line direction and the fault zone direction, and taking into account the surface rupture width of the fault zone's historical stick-slip movement and the scope of influence of the strong earthquake surface rupture effect, the laying range of the fault zone dislocation uneven deformation isolation structure along the line direction is determined.

8. The fault zone dislocation and uneven deformation isolation structure according to claim 7, characterized in that: The closed slide rail (2) is composed of a housing (6), a rotating shaft (7), a spherical ball (8), a baffle (9), a sealing ring (10), an anti-pullout bolt (11), a connecting bolt (12), a connecting plate (13), and a connecting pad (14), and is used to connect two adjacent rubber pad layers (1) and ensure that the two adjacent rubber pad layers (1) can only move horizontally relative to each other along the direction of the fracture zone or rotate axially around the closed slide rail (2). The horizontal movable distance of the closed slide rail (2) is determined based on the creep slip of the fracture zone of the railway roadbed within a hundred-year service life; the spherical ball (8) is located between the housing (6) and the rotating shaft (7) and is used to reduce the friction force of the closed slide rail (2) during axial movement and radial rotation; the anti-pullout bolt (11) is inserted into the baffle (9) to fix the baffle (9) on the housing (6) and is used to limit excessive horizontal relative displacement between two adjacent rubber pad layers (1); the sealing ring (10) is located between the rotating shaft (7) and the baffle (9) and is used to prevent roadbed filler particles from invading the interior of the closed slide rail (2) and hindering the movement of the mechanism.

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