A cable trough cover plate and design method suitable for safe operation of an ultra-high-speed train

Abstract

The present application relates to the field of high-speed railway construction technology, in particular to a cable trough cover plate and design method suitable for safe operation of super high-speed train. The present application adds a pressure relief hole on the basis of the original design of the high-speed railway cable trough cover plate, introduces train wind into the cover plate, and lets the lower surface of the cover plate be subjected to the opposite direction of the upper surface of the fluctuating wind load, so as to produce pressure compensation effect. In this way, when the train wind exerts aerodynamic suction force on the surrounding structure, the total lift of the cable trough cover plate can be reduced, and the risk of being overturned can be reduced; when the train wind exerts aerodynamic pressure on the surrounding structure, the negative lift of the cable trough cover plate can be reduced, thereby delaying fatigue failure. The structure of the above-mentioned cable trough cover plate is simple, and the stress requirement during higher speed driving can be met by adding a pressure relief hole without changing the structure of the existing cable trough cover plate, without increasing the thickness of the cover plate or adding additional fixing measures.

Description

Technical Field

[0001] This invention relates to the field of high-speed railway construction technology, and in particular to a cable trough cover plate and its design method adapted to the safe operation of ultra-high-speed trains. Background Technology

[0002] As the operating speed of high-speed trains continues to increase, the problem of pulsating wind generated during operation is becoming increasingly prominent, especially for ultra-high-speed trains (trains with a maximum operating speed of 350 km / h or higher). Due to the viscosity of air, the high-speed operation of a train will stir up the air near the train walls, causing strong train winds. This applies pulsating wind loads to the surfaces of structures near the running track, leading to structural failure or fatigue damage.

[0003] Cable trough covers, as an important auxiliary structure of high-speed railways, are adjacent track structures not fixed to the main railway structure. They serve not only as walkways for maintenance personnel but also, together with the vertical wall structure, form the troughs for railway communication and power facilities. To prevent rainwater from directly entering the troughs, cable trough covers on high-speed railways often adopt a closed structure, unlike the drainage covers on municipal roads. Cable trough covers for high-speed railways with speeds of 350 km / h and below generally use 6cm thick reinforced concrete slabs or 3cm thick RPC covers. When train operating speeds increase to 400 km / h or higher, the pulsating wind load caused by the train increases dramatically. Existing high-speed railway cable trough covers may be overturned by the instantaneous aerodynamic suction generated by the high-speed train, or may suffer fatigue damage under the repeated impact of the pulsating wind load. This not only affects the normal use of the covers but also poses a significant hidden danger to the safe operation of high-speed trains. Traditional solutions typically involve increasing the thickness of the cover plate or taking measures to fix it in place to reduce the risk of the cover plate being overturned. The drawback of traditional solutions is that they increase the number (or weight) and cost of the cover plate, and also bring many inconveniences to maintenance and repair during operation. At the same time, traditional solutions do not reduce the train pulsating wind load on the cover plate, nor do they solve the problem of fatigue damage to the cover plate under repeated impacts of train pulsating wind loads.

[0004] In addition, relevant literature research shows that as the train speed increases, the pulsating wind load exerted by the train on the surface of structures near the track increases sharply. As the most important design parameter when designing structures near the track, such as cable trough covers, the current railway design specifications only specify the value of the pulsating wind load for trains with speeds of 350 km / h and below. The current specifications cannot guide the design of structures near the track, such as cable trough covers for ultra-high-speed railways with speeds above 350 km / h.

[0005] Therefore, it is necessary to study a new type of cable trough cover plate and corresponding design method that can adapt to the safe operation of ultra-high-speed trains with speeds of 350 km / h and above. Summary of the Invention

[0006] The purpose of this invention is to address the problems of high engineering costs and maintenance difficulties associated with existing high-speed railway cable trough covers, which reduce the risk of the cover being overturned by increasing its thickness or adopting fixing measures. This invention provides a cable trough cover and its design method that are suitable for the safe operation of high-speed trains.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A method for designing cable trough covers adapted to the safe operation of ultra-high-speed trains includes the following steps:

[0009] Step S1: Open pressure relief holes in the cable trough cover plate to obtain the train pulsating wind pressure P on the upper surface of the cover plate. t The formulas for calculating the train speed v, the distance Y from the center of the cover plate to the centerline of the track, and the train pulsating wind pressure P on the lower surface of the cover plate. b Formulas for calculating train speed v, distance Y from the center of the cover plate to the center line of the track, and cover plate opening ratio β;

[0010] Step S2, calculate the lift force of the cable trough cover plate under the action of train wind: F=AB(1-β)(P t -P b )10 -6 ;

[0011] In the formula, F represents the lift force of the cover plate under the action of train wind, in N; A and B represent the lengths of the cover plate along the track and perpendicular to the track, respectively, in mm;

[0012] Step S3: Based on the safety margin M of the cable trough cover plate under the combined action of train wind and structural self-weight, calculate the minimum opening ratio of the pressure relief holes in the cover plate, where:

[0013]

[0014] In the formula, G represents the self-weight of the cover plate in N; t represents the thickness of the cover plate in mm; and γ represents the unit weight of the cover plate in kN / m³. 3 .

[0015] This invention adds pressure relief holes to the original design of high-speed railway cable trough covers, introducing train air into the interior of the cover (i.e., the channel at the bottom of the cover). This causes the lower surface of the cover to experience pulsating wind loads in the opposite direction to the upper surface, thus generating a pressure cancellation effect. In this way, when train air exerts aerodynamic suction on surrounding structures, the total lift (upward direction) of the cable trough cover is reduced, lowering the risk of it being overturned; when train air exerts aerodynamic pressure on surrounding structures, the negative lift (downward direction) of the cable trough cover is reduced, thereby delaying fatigue failure. Furthermore, based on the above structural form, this invention proposes a design concept for the cover's safety margin, providing design guidance for the reasonable opening of the cover, enabling the cable trough cover to have a sufficiently high safety factor without thickening or adding additional fixing measures.

[0016] The cable trough cover obtained by the above design method has a simple structure. Compared with traditional solutions such as increasing the cover thickness or adding cover fixing measures, it can effectively save engineering materials and reduce engineering costs. At the same time, it facilitates maintenance and repair work during operation, making it very suitable for widespread application in ultra-high-speed railway projects.

[0017] As a preferred embodiment of the present invention, in step S1, the pulsating wind pressure on the upper surface of the cover plate is: The pulsating wind pressure on the lower surface of the cover plate is:

[0018] In the formula, a and C t1 C t2 C t3 b, C b1 C b2 C b3 These are all constants, determined according to different working conditions.

[0019] As a further preferred embodiment of the present invention, a∈[6,8], C t1 ∈[0.003, 0.006], C t2 ∈[3,7],C t3 ∈[0.05, 0.3], with good universality.

[0020] As a further preferred embodiment of the present invention, the pulsating wind pressure on the upper surface of the cover plate is calculated by the following formula:

[0021]

[0022] As a further preferred embodiment of the present invention, b∈[6,8], C b1 ∈[0.005, 0.008], C b2 ∈[1,4],C b3 ∈[0.05, 0.3], with good universality.

[0023] As a further preferred embodiment of the present invention, the pulsating wind pressure on the lower surface of the cover plate is calculated by the following formula:

[0024]

[0025] As a preferred embodiment of the present invention, in step S3, the safety margin M≥2.0, indicating high safety.

[0026] In a preferred embodiment of the present invention, the length of the pressure relief hole along the line direction is less than 50 mm, and the length of the pressure relief hole perpendicular to the line direction is less than 100 mm. The pressure relief hole should preferably be a small hole to prevent a large amount of rainwater from entering and thus increasing the difficulty of drainage in the communication and cable troughs.

[0027] The present invention also provides a cable trough cover plate adapted to the safe operation of ultra-high-speed trains, including a cover plate with pressure relief holes.

[0028] This invention adds pressure relief holes to the original design of high-speed railway cable trough covers, introducing train air into the interior of the cover (i.e., the channel at the bottom of the cover). This causes the lower surface of the cover to experience pulsating wind loads in the opposite direction to the upper surface, thus creating a pressure cancellation effect. In this way, when train air exerts aerodynamic suction on surrounding structures, the total lift (upward direction) of the cable trough cover is reduced, lowering the risk of it being overturned; when train air exerts aerodynamic pressure on surrounding structures, the negative lift (downward direction) of the cable trough cover is reduced, thereby delaying fatigue failure. The above-mentioned cable trough cover has a simple structure and can adapt to the stress requirements of higher-speed operation by adding pressure relief holes without changing the existing cable trough cover structure, without increasing the cover thickness or adding additional fixing measures.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. The cable trough cover plate of the present invention adds several pressure relief holes without changing the existing cable trough cover plate structure, so that the train wind is introduced into the inside of the cover plate and the lower surface of the cover plate is subjected to pulsating wind load in the opposite direction to the upper surface, generating a pressure cancellation effect, which greatly reduces the risk of the cover plate being overturned when the ultra-high speed train passes by and delays the fatigue failure of the cover plate.

[0031] 2. The cable trough cover plate of the present invention has a simple structure. Compared with the traditional solutions of increasing the thickness of the cover plate or adding cover plate fixing measures, it can effectively save engineering materials and reduce engineering costs. At the same time, it facilitates maintenance and repair work during operation, such as lifting the cover plate to inspect the cables inside. It is very suitable for widespread application in ultra-high speed railway projects.

[0032] 3. The cable trough cover design method in this invention fills the technical gap in the current design method of cable trough covers for speeds above 350km / h, and effectively solves the design problem of cable trough covers brought about by the development of trains to higher speeds. Attached Figure Description

[0033] Figure 1 This is a structural schematic diagram of an unperforated cable trough cover.

[0034] Figure 2 This is a schematic diagram of a cable trough cover plate with opening type one;

[0035] Figure 3 This is a schematic diagram of a cable trough cover plate with opening type two.

[0036] Figure 4 It is a comparison chart of the time history curves of pulsating wind pressure on the upper and lower surfaces of cover plates with different opening forms;

[0037] Figure 5 This is a schematic diagram showing the pressure cancellation on the upper and lower surfaces of the cover plate after the addition of a pressure relief hole;

[0038] Figure 6 This is a schematic diagram showing the arrangement of cable trough covers on a railway bridge deck;

[0039] Figure 7(a) is a schematic diagram of the time history curve of the pulsating wind pressure on the upper surface of the cable trough cover plate;

[0040] Figure 7(b) is a schematic diagram of the time history curve of the pulsating wind pressure on the lower surface of the cable trough cover plate;

[0041] Figure 8 This is the design drawing of the cable trough cover plate in step three of the embodiment.

[0042] Icons: 1-Cover plate; 2-Pressure relief hole. Detailed Implementation

[0043] The present invention will now be described in detail with reference to the accompanying drawings.

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0045] Example 1

[0046] This embodiment provides a cable trough cover structure adapted to the safe operation of ultra-high-speed trains. Specifically, it adds a certain number of pressure relief holes to the existing 350km / h cable trough cover. Finite element analysis is used to obtain the train's pulsating wind pressure under two conditions: pressure relief holes with and without different opening methods. Figures 1-5As shown, the time history curves of the pulsating wind pressure on the upper and lower surfaces of the cover plate are both composed of a head wave and a tail wave. Both the head wave and the tail wave contain a positive pressure extreme value and a negative pressure extreme value. The head wave is generated when the first vehicle passes through and leaves the cover plate, and the tail wave is generated when the last vehicle passes through and leaves the cover plate.

[0047] Figure 1 It is in an unopened state. Figure 2 and Figure 3 These represent two types of pressure relief hole 2 opening methods: opening type one and opening type two. Figure 3 The opening ratio and number of openings in the second type of opening are both greater than 100%. Figure 2 The first type of opening is shown. Finite element analysis reveals... Figure 4 The diagram displays the time history curves of pulsating wind pressure on the upper and lower surfaces of the cover plate under three conditions: no opening, opening type one, and opening type two. To compare the pulsating wind pressure under these three conditions, the black line represents the no-opening condition, the red line represents the opening type one condition, and the blue line represents the opening type two condition. Figure 5 This is a schematic diagram showing the pressure cancellation on the upper and lower surfaces of the cover plate 1 after the addition of pressure relief hole 2. Analysis shows that when the cover plate does not have pressure relief holes, only the upper surface bears the pulsating wind load generated by the train, and the pulsating wind load on the upper surface is basically the same for different opening types. After adding pressure relief holes, the holes introduce train air into the interior of the cover plate, causing the lower surface to be subjected to a pulsating wind load in the opposite direction to the upper surface, producing a pressure cancellation effect. The second opening type increases the opening ratio compared to the first opening type, and the pulsating wind load and pressure cancellation effect on the lower surface of the cover plate increase accordingly.

[0048] After the pressure relief hole 2 is added to the cover plate 1, when the train wind applies aerodynamic suction to the surrounding structures, the total lift of the cable trough cover plate is reduced, reducing the risk of being overturned. When the train wind applies aerodynamic pressure to the surrounding structures, the negative lift of the cable trough cover plate is reduced, delaying fatigue failure.

[0049] To limit rainwater discharge, the length of the pressure relief hole 2 on the cable trough cover plate 1 along the line direction should be less than 50mm, the length of the pressure relief hole 2 perpendicular to the line direction should be less than 100mm, the distance from the center of the pressure relief hole 2 to the edge of the cover plate 1 should be not less than 50mm, and the pressure relief hole 2 can be various shapes such as round, rectangular, and elliptical.

[0050] It should be noted that the cable trough covers in (ultra)high-speed railways differ from those on municipal roads. The holes on municipal road covers are primarily for drainage and are relatively large. However, the cable trough covers in this design are mainly used for covering cable troughs near railway lines. The holes are for pressure relief, and their design should minimize rainwater ingress. It is undesirable for large amounts of rainwater to enter the channel at the bottom of the cover (previously, covers had very small gaps between them, and waterproofing was installed underneath to drain a small amount of water; therefore, this design eliminates the need for additional waterproofing). Thus, large holes are not recommended. Small holes are generally sufficient to meet design requirements for cable trough covers near railway lines. These holes serve a significant purpose but have minimal impact on the cable's weight.

[0051] Example 2

[0052] Based on Embodiment 1, this embodiment provides a cable trough cover design method adapted to the safe operation of ultra-high-speed trains, including the following steps:

[0053] ①Step 1: Based on the railway design plan, determine the layout and structural dimensions of the cable trough cover plates.

[0054] According to the railway design plan, the distance between the cable trough cover and the center line of the line is Y, the length of the cover along the line is A, the length of the cover perpendicular to the line is B, the thickness of the cover is t, and the opening ratio of the pressure relief holes of the cover (the opening ratio refers to the ratio of the total area of ​​the openings to the total area of ​​the cover) is β.

[0055] ②Step 2: Calculate the lift of the cable trough cover under the action of train wind.

[0056] First, based on ANSYS Fluent fluid calculation software, through numerical simulation of a large number of working conditions, the correlation between the train pulsating wind pressure on the upper and lower surfaces of the cable trough cover plate after adding pressure relief holes and the train speed v, the distance Y from the center of the cover plate to the center line of the track, and the opening ratio β of the cover plate was fitted, and the calculation formula of the train pulsating wind pressure on the upper and lower surfaces of the cover plate after adding pressure relief holes was obtained.

[0057] Numerical simulations show that the pulsating wind pressure distribution on the upper surface of the cover plate is almost unaffected by the openings in the cover plate. The lower surface of the cover plate does not bear pulsating wind pressure without pressure relief holes. After adding pressure relief holes, the pulsating wind pressure distribution increases with the increase of the opening ratio, but the improvement effect gradually slows down with increasing opening ratio. The pulsating wind pressure on the upper and lower surfaces of the cover plate increases approximately quadratically with increasing train speed. The pulsating wind pressure on the upper and lower surfaces of the cover plate increases with decreasing distance from the track centerline. The fitting functions for the pulsating wind pressure on the upper and lower surfaces of the cover plate are as follows:

[0058]

[0059]

[0060] In the above formula, P t P b , representing the train pulsating wind pressure on the upper and lower surfaces of the cover plate, respectively, in Pa; v represents the train speed, in km / h; Y represents the distance from the center of the cover plate to the centerline of the track, in meters; β represents the opening ratio of the pressure relief holes in the cover plate. It should be noted that when using datasets from different operating conditions for fitting, the resulting fitting functions may differ slightly, but the overall trend remains largely unchanged.

[0061] Then, the lift force of the cable trough cover under the action of train wind is calculated using the following formula:

[0062] F=AB(1-β)(P t -P b )10 -6

[0063] In the above formula, F represents the lift force of the cover plate under the action of train wind, in N; A and B represent the lengths of the cover plate along the track and perpendicular to the track, respectively, in mm.

[0064] ③ Step 3: Calculate the safety margin of the cable trough cover plate under the combined action of train wind and structural self-weight, and estimate the minimum opening ratio of the pressure relief hole of the cover plate.

[0065] When a train is running at high speed, the cable trough cover generates upward lift under the aerodynamic suction of the train, posing a risk of overturning. To assess this risk, a safety margin M based on the cover's lift force is proposed, which can be calculated using the following formula:

[0066]

[0067] In the above formula, G represents the self-weight of the cover plate, in N; t represents the thickness of the cover plate, in mm; and γ represents the unit weight of the cover plate, in kN / m³. 3 .

[0068] When the safety margin M < 0, the cover plate's own weight is less than the lift force, and it will be overturned by pneumatic suction. When M > 0, the self-weight is greater than the lift force, and it will not be overturned. The larger the value, the greater the safety margin of the cover plate. Considering that the cover plate also has problems such as wear and vibration in actual engineering, in order to ensure sufficient safety margin, the safety margin should preferably be M ≥ 2.0.

[0069] After the safety margin is determined, the minimum opening rate of the cover plate can be obtained from the above formula. Then, considering the structural requirements of the pressure relief holes on the cover plate, the dimensions and positions of the pressure relief holes are formulated. The length of the pressure relief hole along the line bridge direction is C (0<C<50mm), the length of the pressure relief hole in the direction perpendicular to the line is D (0<D<100mm), the distance from the center of the pressure relief hole to the edge of the cover plate is no less than 50mm, and the pressure relief hole can be in various shapes such as circle, rectangle, and ellipse, completing the design of the cable trough cover plate.

[0070] To further elaborate the design process, this embodiment takes the design scheme of the cable trough cover plate for an ultra-high-speed railway in China that meets the operation condition of 400 km per hour as an example for description. The layout of the cable trough cover plate 1 is as shown in Figure 6 , and the design steps are as follows:

[0071] ① Step 1: According to a certain railway design standard, the distance Y from the cable trough cover plate 1 to the line centerline is 2.5m, the length of the cover plate 1 along the line direction is A=494mm, the length of the cover plate 1 in the direction perpendicular to the line is B=634mm, the thickness t of the cover plate 1 is 30mm, and the opening rate of the pressure relief hole 2 on the cover plate 1 is β.

[0072] ② Step 2: First, calculate the train fluctuating wind pressure on the upper and lower surfaces of the cover plate 1, and the running speed v of the train on this line is 400km / h.

[0073]

[0074]

[0075] Then, calculate the lift force of the cable trough cover plate under the action of train wind.

[0076] F=AB(1-β)(P t -P b )10 -6 =0.31(1-β)(678.8-1045.8β 0.2 )

[0077] ③ Step 3: Calculate the safety margin of the cable trough cover plate under the combined action of train wind and structural self-weight, and the unit weight γ of the cover plate is 25kN / m 3 .

[0078]

[0079] Substituting the lift force F of the cable trough cover plate in step two, the opening ratio β of the pressure relief hole of the cable trough cover plate is calculated to be ≥0.0125. At this time, the time history curves of the train pulsating wind pressure on the upper and lower surfaces of the cable trough cover plate are shown in Figure 7(a) and Figure 7(b). The curves in the figures are formed by superimposing the curves of multiple measuring points on the upper and lower surfaces of the cover plate (in this embodiment, 14 measuring points are arranged on the upper and lower surfaces of the cover plate respectively), that is, different colors represent a measuring point. After analysis, the magnitude of the pulsating wind pressure at different measuring point positions on the upper surface is somewhat different (see the partial enlarged diagram in Figure 7(a) for details). The pressure is the smallest at the measuring point farthest from the train and the largest at the measuring point closest to the train. The extreme value of the pulsating wind pressure on the upper surface of the cover plate is 678.8 Pa. The pulsating wind pressure at different measuring points on the lower surface of the cover plate is basically consistent and the pressure distribution is uniform, as shown in Figure 7(b). The extreme value of the pulsating wind pressure on the lower surface is 475.6 Pa. The pulsating wind pressure on the lower surface is in the same direction as the pulsating wind pressure on the upper surface, and its value is smaller than that on the upper surface, which produces a good pressure cancellation effect.

[0080] Considering the structural requirements of the pressure relief holes in the cover plate, a pressure relief hole is provided at each of the four corners of the cover plate, such as... Figure 8 As shown. The lengths of the pressure relief hole along the line and perpendicular to the line are 20mm and 50mm respectively. The distances from the center of the pressure relief hole to the edge of the cover plate along the line and perpendicular to the line are 95mm and 90mm respectively. The pressure relief hole is elliptical.

[0081] This method generates a pressure relief effect by adding several pressure relief holes to the existing railway cable trough cover design, which greatly reduces the risk of the cover being overturned when a high-speed train passes by, delays the fatigue failure of the cover, and meets the requirements for high-speed train passage without increasing the cover thickness or fixing measures.

[0082] Using the traditional design method, which does not include a pressure relief hole, β = 0, the calculated safety margin of the cover plate under the same conditions (such as size and density) is M = -0.08 < 0, meaning the cover plate will be overturned. If the design requirement of safety margin M ≥ 2.0 is met by increasing the thickness and weight of the cover plate, analysis shows that the cover plate thickness needs to be increased to at least 85 mm. At this point, a thickness of 85 mm corresponds to a safety margin of M = 2.03.

[0083] Compared to designs that increase the thickness of the cover plates, this method only requires the addition of several pressure relief holes, saving a total of 26,000 cubic meters of concrete and approximately 46.68 million yuan in investment. Furthermore, during daily operation, it is often necessary to lift the cable trough covers to inspect the communication and power facilities beneath them. Compared to traditional cover plate designs, this method reduces the weight of each cover plate by 64.7%, greatly facilitating routine maintenance and repair work.

[0084] This method generates a pressure relief effect by adding pressure relief holes. When a train passes through at high speed, the fatigue load borne by the cover plate under the train's pulsating load is ±203.5Pa, while the fatigue load borne by the cover plate under the train's pulsating load under the traditional design method is ±678.2Pa. The train pulsating fatigue load borne by the cable trough cover plate obtained by this method is reduced by 70.0% compared with the traditional design method, which greatly delays the fatigue failure of the cover plate.

[0085] 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 design method for cable trough cover plates adapted to the safe operation of ultra-high-speed trains, characterized in that, Includes the following steps: Step S1: Open pressure relief holes in the cable trough cover plate to obtain the train pulsating wind pressure P on the upper surface of the cover plate. t The formulas for calculating the train speed v, the distance Y from the center of the cover plate to the centerline of the track, and the train pulsating wind pressure P on the lower surface of the cover plate. b Formulas for calculating train speed v, distance Y from the center of the cover plate to the center line of the track, and cover plate opening ratio β; In step S1, the pulsating wind pressure on the upper surface of the cover plate is: The pulsating wind pressure on the lower surface of the cover plate is: In the formula, a and C t1 C t2 C t3 b, C b1 C b2 C b3 Both are constants; a∈[6,8], C t1 ∈[0.003, 0.006], C t2 ∈[3,7],C t3 ∈[0.05, 0.3]; b∈[6, 8], C b1 ∈[0.005, 0.008], C b2 ∈[1,4],C b3 ∈[0.05, 0.3]; Step S2, calculate the lift force of the cable trough cover plate under the action of train wind: F=AB(1-β)(P t -P b )10 -6 ; In the formula, F represents the lift force of the cover plate under the action of wind from the train, and the unit is N; A and B represent the lengths of the cover plate along and perpendicular to the track, respectively, in mm. Step S3: Based on the safety margin M of the cable trough cover plate under the combined action of train wind and structural self-weight, calculate the minimum opening ratio of the pressure relief holes in the cover plate, where: In the formula, G represents the self-weight of the cover plate in N; t represents the thickness of the cover plate in mm; and γ represents the unit weight of the cover plate in kN / m³. 3 .

2. The cable trough cover design method for safe operation of ultra-high-speed trains according to claim 1, characterized in that, The pulsating wind pressure on the upper surface of the cover plate is calculated using the following formula:

3. The cable trough cover design method for safe operation of ultra-high-speed trains according to claim 1, characterized in that, The pulsating wind pressure on the lower surface of the cover plate is calculated using the following formula:

4. A cable trough cover design method for safe operation of ultra-high-speed trains according to any one of claims 1-3, characterized in that, In step S1, the calculation formula for the train pulsating wind load on the cover plate surface is obtained based on multi-condition numerical analysis fitting.

5. A cable trough cover design method for safe operation of ultra-high-speed trains according to any one of claims 1-3, characterized in that, In step S3, the safety margin M ≥ 2.

0.

6. A design method for a cable trough cover plate adapted to the safe operation of ultra-high-speed trains according to any one of claims 1-3, characterized in that, The length of the pressure relief hole along the line direction is less than 50mm, and the length of the pressure relief hole perpendicular to the line direction is less than 100mm.

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