Tail end protection system of rail transit test line

Abstract

The invention relates to a rail transit test line tail end protection system, which is characterized in that a plurality of deceleration energy consumption sections are continuously arranged on a rail transit test line tail end installation foundation along the longitudinal direction; the hardness and the energy consumption capacity per unit length of the rear deceleration energy consumption section in the two longitudinal adjacent deceleration energy consumption sections are larger than those of the front deceleration energy consumption section, and the deceleration energy consumption section with the small hardness has small damage to the test vehicle; the deceleration energy consumption section with the small energy consumption capacity per unit length has small acceleration on deceleration of the test vehicle, so that the test vehicle firstly passes through the soft deceleration energy consumption section with the small energy consumption capacity per unit length for deceleration energy consumption and then is transited to the hard deceleration energy consumption section with the large energy consumption capacity per unit length for deceleration energy consumption. A progressive energy consumption mode is adopted, so that the damage of instantaneous impact force on a test vehicle during train deceleration is reduced, and the length of a deceleration energy consumption section needing to be set can be reduced.

Description

Technical Field

[0001] This invention relates to the field of end protection technology for rail transit test lines, and particularly to an end protection system for rail transit test lines. Background Technology

[0002] Ultra-high-speed rail transit systems require high-speed tests exceeding 600 km / h to verify their technology. Existing protection systems in the transportation sector mainly consist of wheel stops and flexible safety nets. Wheel stops are primarily used to prevent rail transit trains from derailing at low speeds, with a protection speed generally not exceeding 25 km / h. Flexible safety nets are mainly used for slope protection, primarily protecting against falling rocks at speeds of approximately 90 km / h. Neither of these systems can meet the end-of-line protection speed requirements of high-speed or even ultra-high-speed rail transit tests. In other words, existing rail transit end-of-line protection systems cannot withstand the impact of uncontrolled derailment at extremely high speeds, potentially causing serious accidents such as test trains derailing.

[0003] Chinese utility model patent application CN217687900U discloses a braking system for a maglev pipeline test line, including a braking zone on the maglev track and a braking structure on the maglev train. The braking zone includes at least one buffer section, and the buffer section includes a buffer zone located at the bottom of the maglev track, with a buffer solution provided in the buffer zone. The braking structure includes buffer members located on both sides of the maglev train's moving part, with the buffer members at least partially overlapping the buffer solution in the vertical direction, so that when the maglev train enters the braking zone, the buffer members at least partially extend into the buffer solution to decelerate the maglev train. This application proposes to install a buffer component on the maglev train and a buffer zone on the maglev track. When the maglev train passes through the buffer zone, the buffer component is immersed in the buffer solution of the buffer zone, and the buffer solution forms an effective braking effect on the buffer component to absorb the kinetic energy of the maglev train and achieve braking. However, this structure requires modification of the bottom of the maglev track, which is complex and will lead to high testing costs. In addition, the acceleration of the buffer solution for decelerating the maglev train is equal. When the acceleration is set too high, the train will be subjected to a large instantaneous impact force during deceleration, which may easily damage the train. When the acceleration is set too low, the buffer zone will be too long, which will greatly increase the cost. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing rail transit braking systems, which have equal braking acceleration. When the acceleration is set too high, the train will be subjected to a large instantaneous impact force during deceleration, which can easily damage the train. Conversely, when the acceleration is set too low, the buffer zone will be too long, which greatly increases the cost. This invention provides a rail transit test line end protection system.

[0005] This invention provides an end protection system for a rail transit test line, comprising a plurality of deceleration energy dissipation sections disposed on an installation foundation at the end of the rail transit test line. All the deceleration energy dissipation sections are arranged continuously in the longitudinal direction of the installation foundation. The hardness of the rear deceleration energy dissipation section in two longitudinally adjacent sections is greater than that of the front deceleration energy dissipation section. The energy dissipation capacity per unit length of the rear deceleration energy dissipation section in two longitudinally adjacent sections is greater than that of the front deceleration energy dissipation section.

[0006] Preferably, the deceleration energy-consuming sections arranged sequentially from front to back at the end of the rail transit test line are a first deceleration energy-consuming section, a second deceleration energy-consuming section, and a third deceleration energy-consuming section. The preset total energy absorption of the second deceleration energy-consuming section is greater than the preset total energy absorption of the third deceleration energy-consuming section, and the preset total energy absorption of the third deceleration energy-consuming section is greater than the preset total energy absorption of the first deceleration energy-consuming section. Preferably, all of the aforementioned deceleration energy-consuming sections are material piles.

[0007] Preferably, the material of the first deceleration energy consumption section is fine sand, the material of the second deceleration energy consumption section is cohesive sand, and the material of the third deceleration energy consumption section is gravel or pebbles.

[0008] Preferably, the preset energy absorption of the first deceleration energy consumption stage accounts for 25%-20% of the total preset energy absorption, the preset energy absorption of the second deceleration energy consumption stage accounts for 45%-55% of the total preset energy absorption, and the preset energy absorption of the third deceleration energy consumption stage accounts for 30%-25% of the total preset energy absorption. Preferably, the front end face of the first deceleration energy dissipation section adopts a sloping end face with a gradually increasing height from front to back; Alternatively, the front end face of the first deceleration energy-consuming section may be a combination of a first ramp end face, a plane, and a second ramp end face. The height of both the first ramp end face and the second ramp end face gradually increases from front to back. The front and rear sides of the plane are adjacent to the top side of the first ramp end face and the bottom side of the second ramp end face. Preferably, a third ramp end face is provided between the first deceleration energy consumption section and the second deceleration energy consumption section, and the height of the third ramp end face gradually decreases from front to back; And / or, a fourth ramp end face is provided between the second deceleration energy consumption section and the third deceleration energy consumption section, and the height of the fourth ramp end face gradually decreases from front to back.

[0009] Preferably, an energy-absorbing structure is embedded in part or all of the deceleration energy-consuming section, and the energy-absorbing structure is capable of crushing and consuming energy. And / or, the installation base is further provided with an end retaining wall, which is adjacent to the rear end face of the third deceleration energy consumption section.

[0010] Preferably, the top surface of the deceleration energy dissipation section is higher than the top surface of the test vehicle, and the lateral width of the deceleration energy dissipation section is greater than the width of the test vehicle; And / or, a rain shelter is provided above the top of the deceleration energy consumption section, the rain shelter is supported on both sides of the mounting base, the height of the rain shelter is higher than the top height of the test vehicle, and the width of the rain shelter is greater than the lateral width of the deceleration energy consumption section.

[0011] Preferably, the installation foundation includes a top plate, side plates, columns, beams, and inclined plates; The height of the top surface of the top plate is lower than or equal to the height of the track surface. The side plates are located on both sides of the top plate and are continuously arranged on the corresponding sides. The space above the top plate and between the two side plates is used to install the deceleration energy dissipation section. The crossbeam is horizontally positioned below the front end of the top plate along the end of the rail transit test line. Both ends of the crossbeam are connected to the bottom surface of the front end of the top plate via the columns. The front end of the inclined plate is connected to the rear side of the crossbeam. The height of the inclined plate gradually increases from front to back. The lower part of the columns and the inclined plate are both buried underground.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides an end-protection system for a rail transit test line. It involves continuously installing several deceleration energy-dissipating sections longitudinally along a foundation at the end of the test line. The harderness of the rear deceleration energy-dissipating section in a pair of longitudinally adjacent sections is greater than that of the front section. The energy dissipation capacity per unit length of the rear section is also greater than that of the front section. The lower-hardness deceleration energy-dissipating section causes less damage to the test vehicle, and the lower energy dissipation capacity per unit length results in a smaller acceleration for the test vehicle. This allows the test vehicle to first decelerate through the softer sections with lower energy dissipation capacity per unit length, and then transition to the harder sections with higher energy dissipation capacity per unit length. This reduces damage to the rail transit train. Furthermore, the progressive energy dissipation method increases the acceleration gradient during deceleration, thus reducing the damage to the test vehicle from the instantaneous impact force during train deceleration. It also reduces the required length of the deceleration energy-dissipating sections, significantly lowering costs. Attached Figure Description

[0013] Figure 1 This is a side view of the end protection system for the rail transit test line described in this invention; Figure 2 This is a front view of the end protection system for the rail transit test line described in this invention; Figure 3 This is a plan view of the end protection system of the rail transit test line described in this invention.

[0014] The diagram is marked with the following symbols: 1. Installation foundation; 11. Top plate; 12. Column; 13. Inclined plate; 14. Horizontal beam; 15. End retaining wall; 16. Side retaining wall; 2. First deceleration and energy dissipation section; 21. First slope end face; 22. Plane; 23. Second slope end face; 24. Third slope end face; 25. Fourth slope end face; 201. First slope side face; 202. Second slope side face; 203. Third slope side face; 3. Second deceleration and energy dissipation section; 4. Third deceleration and energy dissipation section; 5. Energy absorption structure; 6. Rain shelter; 61. Support. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0016] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0017] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0018] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0019] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0020] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0021] Example 1 like Figures 1-3As shown, a rail transit test line end protection system is provided. Test vehicles enter the end protection system for deceleration and braking at the end of the test. The rail transit test line end protection system includes several deceleration energy dissipation sections installed on a mounting base 1 at the end of the rail transit test line. All the deceleration energy dissipation sections are longitudinally continuous on the mounting base 1. The rearmost deceleration energy dissipation section in a longitudinally adjacent pair of sections (…) Figure 1 The hardness of the section (left-hand front, right-hand rear) is greater than that of the front deceleration energy dissipation section. Compared to the test vehicle impacting the harder deceleration energy dissipation section, the test vehicle suffers less damage when impacting the softer deceleration energy dissipation section. Among two longitudinally adjacent deceleration energy dissipation sections, the energy dissipation capacity per unit length of the rear section is greater than that of the front section. Here, the unit length refers to the longitudinal unit length of the end protection system of the rail transit test line. If the longitudinal length of the end protection system of the rail transit test line is 1m and the height and width are equal, the stronger the energy dissipation capacity per unit length, the greater the deceleration acceleration caused to the test vehicle, that is, the faster the deceleration. However, the greater the deceleration acceleration, the greater the impact force, and the greater the instantaneous impact force, the stronger the destructive power, and the greater the damage to the test vehicle.

[0022] The end protection system of the rail transit test line described in this embodiment allows the test vehicle to first decelerate and dissipate energy through a softer deceleration energy dissipation section with a smaller energy dissipation capacity per unit length, and then transition to a harder deceleration energy dissipation section with a larger energy dissipation capacity per unit length. This reduces the damage to the rail transit train caused by the deceleration energy dissipation section. Furthermore, by adopting a progressive energy dissipation method, the acceleration gradient of deceleration becomes larger, which reduces the damage to the test vehicle caused by the instantaneous impact force change during train deceleration. In addition, it can reduce the length of the deceleration energy dissipation section that needs to be set, greatly reducing costs.

[0023] like Figure 1 As shown, the left and right directions are the longitudinal direction of the rail transit test line. The test vehicle travels from left to right and enters the end protection system of the rail transit test line to decelerate and brake.

[0024] In optional implementations, such as Figure 1As shown, the deceleration energy-dissipating sections arranged sequentially from front to back at the end of the rail transit test line are the first deceleration energy-dissipating section 2, the second deceleration energy-dissipating section 3, and the third deceleration energy-dissipating section 4. That is, the test vehicle decelerates and dissipates energy by passing through the first deceleration energy-dissipating section 2, the second deceleration energy-dissipating section 3, and the third deceleration energy-dissipating section 4 sequentially from left to right. The preset total energy absorption of the second deceleration energy-dissipating section 3 is greater than that of the third deceleration energy-dissipating section 4, and the preset total energy absorption of the third deceleration energy-dissipating section 4 is greater than that of the first deceleration energy-dissipating section 2. The hardness and energy dissipation capacity per unit length of the first deceleration energy-dissipating section 2, the second deceleration energy-dissipating section 3, and the third deceleration energy-dissipating section 4 all gradually increase. By setting the preset total energy absorption of the first deceleration energy-dissipating section 2 to a minimum, the overall length of the end protection system of the rail transit test line can be avoided from being set too large. The second deceleration energy dissipation section 3 is set to its maximum preset energy absorption capacity, allowing it to consume as much of the test vehicle's kinetic energy as possible. This results in the test vehicle colliding with the harder third deceleration energy dissipation section 4, causing a smaller initial kinetic energy and thus reducing the damage to the test vehicle. Furthermore, during the design phase, the total preset energy absorption capacity and the preset energy absorption capacity of the third deceleration energy dissipation section 4 can be determined first. This allows for the determination of the longitudinal length of the third deceleration energy dissipation section 4, minimizing the damage to the test vehicle. Based on this, the lengths of the first deceleration energy dissipation section 2 and the second deceleration energy dissipation section 3 are determined according to the length of the mounting base 1, minimizing the length of the first deceleration energy dissipation section 2. In other words, this design approach minimizes the damage to the test vehicle while reducing the length of the first deceleration energy dissipation section 2, thereby significantly reducing costs.

[0025] In an optional implementation, all the deceleration energy dissipation sections are material piles, mainly constructed by stacking materials. This allows for deceleration and energy dissipation of the test vehicle while preventing excessive instantaneous impact that could cause severe damage. Further, the material for the first deceleration energy dissipation section 2 is fine sand, the material for the second deceleration energy dissipation section 3 is cohesive sand, and the material for the third deceleration energy dissipation section 4 is gravel or pebbles. In this embodiment, it is preferred that the third deceleration energy dissipation section 4 is constructed using gravel. For example, the first deceleration energy consumption section 2 is composed of relatively loose fine sand particles with a particle size greater than 0.075mm. It does not require compaction. When the test vehicle enters the first deceleration energy consumption section 2, due to the small size of the fine sand particles, the sand will be instantly squeezed apart like a liquid upon impact. However, the fine sand can absorb the kinetic energy of the test vehicle, causing it to decelerate. Because the collision can instantly dissipate force, excessive damage to the test vehicle can be avoided. The second deceleration energy consumption section 3 uses cohesive sand with cohesive bonding and high dispersion, which has a certain internal friction angle and is more difficult to flow than pure fine sand. When the test vehicle impacts the cohesive sand, it can provide deceleration... The acceleration is greater and the energy consumption is faster. Although the drag is greater, the fine sand in the first deceleration energy consumption section 2 has already reduced the kinetic energy of the test vehicle, thus avoiding excessive damage to the test vehicle. The gravel in the third deceleration energy consumption section 4 uses fine gravel with an average particle size of 1mm-10mm. Its large particles can form a stable skeleton structure to resist huge lateral thrust and shear force, so the deceleration acceleration it provides is greater than that of cohesive sand, and the energy consumption is faster. Although the drag is greater, the fine sand in the first deceleration energy consumption section 2 and the cohesive sand in the second deceleration energy consumption section 3 have successively reduced the kinetic energy of the test vehicle, thus avoiding excessive damage to the test vehicle.

[0026] Before the test, the total kinetic energy of the test vehicle will be estimated according to the test conditions. The total energy that the end protection system of the rail transit test line needs to absorb is the total kinetic energy of the test vehicle. Therefore, the total preset energy absorption amount of the end protection system of the rail transit test line can be obtained based on the total kinetic energy of the test vehicle. The energy absorption of the end protection system of the rail transit test line mainly relies on all deceleration energy consumption sections. Therefore, the total preset energy absorption amount can be allocated to each deceleration energy consumption section. That is, each deceleration energy consumption section has a preset energy absorption amount. Based on the preset energy absorption amount, the material and size of the corresponding deceleration energy consumption section can be selected. Furthermore, when the material of the first deceleration energy-consuming section 2 is fine sand, the material of the second deceleration energy-consuming section 3 is cohesive sand, and the material of the third deceleration energy-consuming section 4 is gravel, the preset energy absorption of the first deceleration energy-consuming section 2 accounts for 25%-20% of the total preset energy absorption, the preset energy absorption of the second deceleration energy-consuming section 3 accounts for 45%-55% of the total preset energy absorption, and the preset energy absorption of the third deceleration energy-consuming section 4 accounts for 30%-25% of the total preset energy absorption. While minimizing the damage to the test vehicle, the length of the first deceleration energy-consuming section 2 should be minimized, thereby significantly reducing costs. Specifically, with the preset energy absorption of the first deceleration energy-consuming section 2 accounting for 25%-20% of the total preset energy absorption, the lower the percentage, the shorter the length of the first deceleration energy-consuming section 2, and consequently, the shorter the length of the end protection system of the rail transit test line. Similarly, with the preset energy absorption of the third deceleration energy-consuming section 4 accounting for 30%-25% of the total preset energy absorption, the lower the degree of damage to the test vehicle.

[0027] In an optional implementation, the front end face of the first deceleration energy dissipation section 2 is a sloping end face with a gradually increasing height from front to back. The test vehicle first contacts the front end face of the first deceleration energy dissipation section 2 at the bottom, and then at the top. The resistance is greater at the bottom and less at the top. During the deceleration process, the lower part of the test vehicle decelerates faster and the upper part decelerates slower, causing the test vehicle to nod and avoid derailment. In optional implementations, such as Figure 1 As shown, the front end face of the first deceleration energy-consuming section 2 adopts a combination of a first inclined end face 21, a plane 22, and a second inclined end face 23. The height of both the first inclined end face 21 and the second inclined end face 23 gradually increases from front to back. The front and rear sides of the plane 22 are adjacent to the top side of the first inclined end face 21 and the bottom side of the second inclined end face 23. That is, the first inclined end face 21 makes the lower part of the test vehicle decelerate faster and the upper part decelerate slower during the deceleration process, causing the test vehicle to nod and avoid derailment. The plane 22 can smooth the deceleration process of the lower part of the test vehicle, making the process more stable. The second inclined end face 23 makes the lower part of the upper part of the rail transit train decelerate faster and the upper part decelerate slower, causing the test vehicle to nod and avoid derailment.

[0028] In optional implementations, such as Figure 1As shown, a third ramp end face 24 is provided between the first deceleration energy dissipation section 2 and the second deceleration energy dissipation section 3. The height of the third ramp end face 24 gradually decreases from front to back. The third ramp end face 24 is provided at the junction of the first deceleration energy dissipation section 2 and the second deceleration energy dissipation section 3, so that the cross section of the end of the first deceleration energy dissipation section 2 gradually decreases from front to back, while the cross section of the beginning of the second deceleration energy dissipation section 3 gradually increases from front to back. The energy dissipation capacity per unit length of the second deceleration energy dissipation section 3 is greater than that of the first deceleration energy dissipation section 2. This means that when the test vehicle gradually passes through the junction of the first deceleration energy dissipation section 2 and the second deceleration energy dissipation section 3 from front to back, the resistance gradually increases, thereby achieving a smooth transition of resistance and gradually increasing the deceleration acceleration of the test vehicle, reducing the degree of damage to the test vehicle.

[0029] In optional implementations, such as Figure 1 As shown, a fourth ramp end face 25 is provided between the second deceleration energy dissipation section 3 and the third deceleration energy dissipation section 4. The height of the fourth ramp end face 25 gradually decreases from front to back. The fourth ramp end face 25 is provided at the junction of the second deceleration energy dissipation section 3 and the third deceleration energy dissipation section 4, so that the cross-section of the end of the second deceleration energy dissipation section 3 gradually decreases from front to back, while the cross-section of the beginning of the third deceleration energy dissipation section 4 gradually increases from front to back. The energy dissipation capacity per unit length of the third deceleration energy dissipation section 4 is greater than that of the second deceleration energy dissipation section 3. This means that when the test vehicle gradually passes through the junction of the second deceleration energy dissipation section 3 and the third deceleration energy dissipation section 4 from front to back, the resistance gradually increases, thereby achieving a smooth transition of resistance and gradually increasing the deceleration acceleration of the test vehicle, reducing the degree of damage to the test vehicle.

[0030] In optional implementations, such as Figure 2 and Figure 3 As shown, the first deceleration energy consumption section 2 has a first ramp side 201 on both sides in the lateral direction, the second deceleration energy consumption section 3 has a second ramp side 202 on both sides in the lateral direction, and the third deceleration energy consumption section 4 has a third ramp side 203 on both sides in the lateral direction. The height of the first ramp side 201, the second ramp side 202 and the third ramp side 203 gradually decreases from the middle of the lateral direction to both sides. This setting makes the resistance at the bottom greater and the resistance at the top less, so that the vehicle nods during deceleration and avoids derailment.

[0031] In an optional implementation, if the speed of the test vehicle cannot be reduced to 0 through the first deceleration energy dissipation stage 2, the second deceleration energy dissipation stage 3, and the third deceleration energy dissipation stage 4, such as Figure 1 As shown, the energy-absorbing structure 5 can be embedded in part or all of the deceleration and energy-consuming section, and the energy-absorbing structure 5 can crush and consume energy. Figure 1 In this structure, the energy-absorbing structure 5 adopts a cylindrical shape, which can be stacked horizontally or vertically. The energy-absorbing structure 5 can also have a regular polygonal cross-section, forming a honeycomb structure. For example... Figure 1 As shown, the energy-absorbing structure 5 is set at the junction of the first deceleration energy-consuming section 2 and the second deceleration energy-consuming section 3, or at the junction of the second deceleration energy-consuming section 3 and the third deceleration energy-consuming section 4, making construction and installation more convenient and easier.

[0032] In an optional implementation, when the speed of the test vehicle cannot be reduced to 0 by the first deceleration energy dissipation section 2, the second deceleration energy dissipation section 3 and the third deceleration energy dissipation section 4, an end barrier 15 can be set on the mounting base 1. The end barrier 15 is adjacent to the rear end face of the third deceleration energy dissipation section 4 and is used to forcibly intercept the vehicle.

[0033] In this embodiment, the top surface of the deceleration energy dissipation section is higher than the top surface of the test vehicle, and the lateral width of the deceleration energy dissipation section is greater than the width of the test vehicle, which can dissipate energy from the overall cross-section of the test vehicle.

[0034] In an optional embodiment, when all the deceleration energy-consuming sections are material piles, in order to prevent rainwater from causing changes in the hardness and energy consumption capacity per unit length of the material piles, a rain shelter 6 is provided above the top of the deceleration energy-consuming section. The rain shelter 6 is supported by two side supports 61 installed on both sides of the mounting base 1. The height of the rain shelter 6 is higher than the top surface height of the test vehicle, and the width of the rain shelter 6 is greater than the lateral width of the deceleration energy-consuming section. The rain shelter 6 does not affect the passage of the test vehicle, but can prevent all the deceleration energy-consuming sections from getting wet.

[0035] In optional implementations, such as Figure 1 and Figure 2 As shown, the installation base 1 includes a top plate 11, side plates, columns 12, crossbeams 14, and inclined plates 13. The top surface of the top plate 11 is lower than or equal to the height of the track surface, so that the deceleration energy-consuming section can cover the bottom of the test vehicle. The side plates are located on both sides of the top plate 11 and are continuously arranged on the corresponding sides. The space above the top plate 11 and between the two side plates is used to install the deceleration energy-consuming section, which can limit the setting range of the deceleration energy-consuming section. When all the deceleration energy-consuming sections are material piles, when the test vehicle passes through the deceleration energy-consuming section, the side plates can prevent some of the material from splashing too much to both sides. The top of the side plates can also be used as a fixed base for the supports 61 on both sides of the rain shelter 6.

[0036] The crossbeam 14 is transversely positioned below the front end of the top plate 11 along the end of the rail transit test line. Both ends of the crossbeam 14 are connected to the bottom front end of the top plate 11 via columns 12. The front end of the inclined plate 13 is connected to the rear side of the crossbeam 14, and the height of the inclined plate 13 gradually increases from front to back. The lower parts of the columns 12 and the inclined plate 13 are both buried underground. Compared to a large installation foundation 1, this structure, consisting of a top plate 11, transverse columns 12 on both sides, a crossbeam 14, and an inclined plate 13, is simpler to construct and lower in cost. Furthermore, the lower parts of the buried columns 12 and the gradually increasing height of the inclined plate 13 from front to back increase resistance and provide better impact resistance, preventing the entire end protection system of the rail transit test line from moving under the impact of the test vehicle. Additionally, the installation foundation 1 and the end retaining wall 15 can be a single, integrally cast reinforced concrete structure, resulting in better overall load-bearing performance.

[0037] construction Figures 1-3 The described end protection system for the rail transit test line involves constructing and installing a foundation 1 at the end of the test line. Fine sand is piled between the two side plates of the foundation 1 to form the first deceleration energy-dissipating section 2. A cylindrical energy-absorbing structure 5 is pre-embedded at the rear end of the first deceleration energy-dissipating section 2. Then, the first slope end face 21, plane 22, second slope end face 23, third slope end face 24, and first slope side face 201 are shaped to form a stepped structure. Next, the cylindrical energy-absorbing structures 5 at the front and rear ends of the second deceleration energy-dissipating section 3 are installed, and cohesive sand is piled up in the second deceleration energy-dissipating section 3. The second deceleration energy-consuming section 3 is modified by the third slope side 203 and the second slope side 202 to form a stepped structure; finally, gravel is piled up for the third deceleration energy-consuming section 4, and a rain shelter 6 is set on top. This end protection system of the rail transit test line realizes end protection for the ultra-high-speed rail transit system, and the material pile can be manually restored after being impacted, which can meet the needs of repeated testing scenarios such as test lines; its structure is simple and the cost is controllable; and the configuration specifications of fine sand, cohesive sand and gravel can be changed to meet the needs of different speed and different load tests.

[0038] The end protection system of the rail transit test line described in this embodiment avoids rigid impact by dissipating energy through progressive energy dissipation of fine sand, cohesive sand and gravel. By slowing down the deceleration process as much as possible, it achieves controllable buffering when the ultra-high speed test vehicle runs off the track. It can meet the end protection requirements of test lines under extremely high speed and heavy load, and is reusable with controllable cost.

[0039] This embodiment also provides a specific example of how the end protection system of a rail transit test line is applied to a high-speed maglev test line, such as... Figure 1As shown, fine sand, cohesive sand, and gravel are stacked in sequence. The cross-section of the fine sand pile is trapezoidal, wider at the bottom and narrower at the top. The lighter fine sand pile is longer, so when the vehicle first enters the fine sand, the initial resistance is relatively small, avoiding excessive instantaneous resistance that could cause a huge impact overload and consume the vehicle's kinetic energy. When the vehicle enters the cohesive sand, the resistance provided by the cohesive sand pile is significantly enhanced, further reducing the vehicle speed through greater interparticle friction and viscosity. The gravel pile has the highest density, and during the braking process, the rolling, friction, and crushing of the gravel consume the vehicle's last kinetic energy, ensuring effective braking.

[0040] The following is a calculation example: This case study considers a high-speed maglev test track primarily for testing a test vehicle with dimensions of 6m x 2.7m x 1.9m, a weight of 4t, and a speed of 600km / h. For example... Figure 3 As shown, the end-of-line protection system has a width L0 = 7.5m. The kinetic energy absorption ratios of the fine sand pile, cohesive sand pile, and gravel pile are set to 25%, 45%, and 30%, respectively. Referring to the maximum deceleration of 25-40g in automobile crash tests, the fine sand pile, cohesive sand pile, and gravel pile are arranged in a stepped cross-section to improve their braking effect. Calculations are performed based on the deceleration accelerations of 6g, 12g, and 18g for fine sand, cohesive sand, and gravel, respectively.

[0041] The total kinetic energy of the test vehicle is E = 0.5 * 4000 * (600 / 3.6). 2 =55.56MJ, The kinetic energy absorbed by the fine sand pile is E1 = 55.56 * 0.25 = 13.89 MJ; The kinetic energy absorbed by the cohesive sand pile is E2 = 55.56 * 0.45 = 25 MJ; The gravel pile absorbs kinetic energy E3 = 55.56 * 0.3 = 16.67 MJ.

[0042] Then the estimated length of the sand pile is L = E / (m·a), and MJ = 10. 6 J = e6J, then: The length of the fine sand pile is L1 = 13.89e6 / (4000 * 6 * 9.8) = 59m; The length of the cohesive sand pile L2 = 25e6 / (4000 * 12 * 9.8) = 53m; The length of the gravel pile is L3 = 16.67e6 / (4000 * 18 * 9.8) = 24m.

[0043] At this point, the lengths of the fine sand, cohesive sand, and gravel piles are 59m, 53m, and 24m, respectively.

[0044] In addition, by burying a crushable energy-absorbing structure 5 in cohesive sand and gravel piles, the kinetic energy of the test vehicle can be absorbed, further improving the braking effect of the protection system and shortening the braking distance.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A protection system for the end of a rail transit test line, characterized in that, It includes several deceleration energy dissipation sections set on the installation foundation (1) at the end of the rail transit test line. All the deceleration energy dissipation sections are set continuously in the longitudinal direction of the installation foundation (1). The hardness of the deceleration energy dissipation section that is later in two longitudinally adjacent deceleration energy dissipation sections is greater than that of the deceleration energy dissipation section that is earlier in two longitudinally adjacent deceleration energy dissipation sections. The energy dissipation capacity per unit length of the deceleration energy dissipation section that is later in two longitudinally adjacent deceleration energy dissipation sections is greater than that of the deceleration energy dissipation section that is earlier in two longitudinally adjacent deceleration energy dissipation sections.

2. The end protection system for a rail transit test line according to claim 1, characterized in that, The deceleration energy-consuming sections set sequentially from front to back at the end of the rail transit test line are the first deceleration energy-consuming section (2), the second deceleration energy-consuming section (3), and the third deceleration energy-consuming section (4). The preset total energy absorption of the second deceleration energy-consuming section (3) is greater than the preset total energy absorption of the third deceleration energy-consuming section (4), and the preset total energy absorption of the third deceleration energy-consuming section (4) is greater than the preset total energy absorption of the first deceleration energy-consuming section (2).

3. The end protection system for a rail transit test line according to claim 2, characterized in that, All of the aforementioned deceleration and energy-consuming sections are material piles.

4. The end protection system for a rail transit test line according to claim 3, characterized in that, The material of the first deceleration energy consumption section (2) is fine sand, the material of the second deceleration energy consumption section (3) is cohesive sand, and the material of the third deceleration energy consumption section (4) is gravel or pebbles.

5. The end protection system for a rail transit test line according to claim 4, characterized in that, The preset energy absorption of the first deceleration energy consumption stage (2) accounts for 25%-20% of the total preset energy absorption, the preset energy absorption of the second deceleration energy consumption stage (3) accounts for 45%-55% of the total preset energy absorption, and the preset energy absorption of the third deceleration energy consumption stage (4) accounts for 30%-25% of the total preset energy absorption.

6. The end protection system for a rail transit test line according to claim 4, characterized in that, The front end face of the first deceleration energy consumption section (2) adopts a sloping end face with a gradually increasing height from front to back; Alternatively, the front end face of the first deceleration energy dissipation section (2) adopts a combination of a first ramp end face (21), a plane (22), and a second ramp end face (23). The height of the first ramp end face (21) and the second ramp end face (23) gradually increases from front to back. The front and rear sides of the plane (22) are adjacent to the top side of the first ramp end face (21) and the bottom side of the second ramp end face (23).

7. The end protection system for a rail transit test line according to claim 6, characterized in that, A third ramp end face (24) is provided between the first deceleration energy consumption section (2) and the second deceleration energy consumption section (3), and the height of the third ramp end face (24) gradually decreases from front to back; And / or, a fourth ramp end face (25) is provided between the second deceleration energy dissipation section (3) and the third deceleration energy dissipation section (4), and the height of the fourth ramp end face (25) gradually decreases from front to back.

8. The end protection system for a rail transit test line according to claim 3, characterized in that, Some or all of the deceleration energy-consuming sections are embedded in the energy-absorbing structure (5), which is capable of crushing and consuming energy. And / or, the mounting base (1) is also provided with an end retaining wall (15), which is adjacent to the rear end face of the third deceleration energy dissipation section (4).

9. The end protection system for a rail transit test line according to claim 3, characterized in that, The top surface of the deceleration energy dissipation section is higher than the top surface of the test vehicle, and the lateral width of the deceleration energy dissipation section is greater than the width of the test vehicle. And / or, a rain shelter (6) is provided above the top of the deceleration energy consumption section, and the rain shelter (6) is supported (61) on both sides of the installation base (1). The height of the rain shelter (6) is higher than the top height of the test vehicle, and the width of the rain shelter (6) is greater than the lateral width of the deceleration energy consumption section.

10. A track transit test line end protection system according to any one of claims 1-9, characterized in that, The installation foundation (1) includes a top plate (11), side plates, columns (12), crossbeams (14) and inclined plates (13); The top surface of the top plate (11) is lower than or equal to the height of the track surface. The side plates are located on both sides of the top plate (11) and are continuously arranged on the corresponding sides. The space above the top plate (11) and between the two side plates is used to install the deceleration energy dissipation section. The crossbeam (14) is horizontally positioned below the front end of the top plate (11) along the end of the rail transit test line. Both ends of the crossbeam (14) are connected to the bottom surface of the front end of the top plate (11) through the column (12). The front end of the inclined plate (13) is connected to the rear side of the crossbeam (14). The height of the inclined plate (13) gradually increases from front to back. The lower part of the column (12) and the inclined plate (13) are both buried underground.

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