Method and device for calculating bridge train braking force

Abstract

The application discloses a kind of bridge train braking force calculation method and device, it is related to bridge analysis technical field, the method includes obtaining bridge and train information, and the speed information, deceleration information and time information when train braking;Calculate the corresponding brake force time history load function under the condition that train starts braking after entering bridge;Calculate the corresponding brake force time history load function under the condition that train starts braking when entering bridge;According to the comparison of the brake force time history load function images obtained by calculation under two kinds of conditions, obtain train brake force time history load function.The application can accurately and efficiently calculate the effect of bridge structure in train braking process, so that the calculated value is consistent with the actual value, effectively ensure the safety of bridge structure and train travel.

Description

Technical Field

[0001] This invention relates to the field of bridge analysis technology, specifically to a method and apparatus for calculating the braking force of trains on bridges. Background Technology

[0002] With economic development, long-span railway bridges have seen rapid growth. Existing kilometer-level railway bridges include the Yangtze River Bridge with a main span of 1092m. Train braking is a critical operating condition in the design of long-span railway bridges. During braking, braking force is generated, causing the train to decelerate until it stops. According to relevant railway bridge and culvert design specifications, the braking force should be calculated as 10% of the vertical live load of the train within the calculated length; double-track bridges are calculated based on the braking force of a single track, and three-track or higher bridges are calculated based on the braking force of two tracks.

[0003] The effect of braking force on bridge structures manifests as internal forces and structural deformation. Internal forces affect bridge safety, while structural deformation affects train operation safety. Therefore, accurate calculation of train braking is extremely important. Currently, designers still use the "static method" to determine the effect of braking force on bridge structures.

[0004] Under the braking force of the train, the main girder moves longitudinally along the bridge, and its motion pattern is time-dependent. The bridge structure is equipped with supports and dampers. Supports generate frictional resistance, and dampers generate damping force. These two resistances reduce the magnitude of the bridge structure's motion but correspondingly increase the internal forces in the bridge towers or piers. However, the commonly used "static method" for calculating the effect of braking force on the bridge structure cannot account for the effects of support friction and dampers, leading to results that differ significantly from the actual values.

[0005] The time-related calculation method is the "dynamic time-history method," which can consider support friction and damper effects. Train braking force is crucial as a time-history load input in this method. However, to date, there is no clear data on how train braking force is converted into a time-history load. Therefore, the calculation of the effect of train braking force on bridge structures can only be performed using the inaccurate "static method," resulting in a significant deviation between the calculated and actual values, thus affecting the safety of bridges and train operation. Summary of the Invention

[0006] In view of the deficiencies in the existing technology, the purpose of this invention is to provide a method and device for calculating the braking force of a bridge train, which can accurately and efficiently calculate the effect of the bridge structure during the train braking process, so that the calculated value is consistent with the actual value, and effectively ensure the safety of the bridge structure and train operation.

[0007] To achieve the above objectives, the present invention provides a method for calculating the braking force of a bridge train, which specifically includes the following steps:

[0008] Obtain information about bridges and trains, as well as speed, deceleration, and timing information during train braking;

[0009] Calculate the braking force time-history load function when braking begins after the train has fully entered the bridge.

[0010] Calculate the braking force time-history load function when the train begins braking as it enters the bridge.

[0011] By comparing the calculated braking force time-history load function images under the two scenarios, the train braking force time-history load function is obtained.

[0012] Based on the above technical solution, the acquisition of bridge and train information, as well as train braking speed, deceleration, and timing information, specifically includes:

[0013] Obtain the bridge length, train length, train weight, train speed at the start of braking, average deceleration during braking, and the deceleration rate from the start of braking until it reaches 1 m / s². 2 The time required for the train to come to a complete stop after it begins braking, and the time required for the train to come to a complete stop after it begins braking.

[0014] Based on the above technical solution, the specific steps for calculating the braking force time-history load function when the train has fully entered the bridge and begins braking include:

[0015] Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted.

[0016] Calculate the time required for the entire train to exit the bridge after braking begins once it has fully entered the bridge, and based on this time:

[0017] When braking begins after the entire train has entered the bridge, and the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after braking begins, then the function corresponding to the line graph of braking force versus train travel time is the braking force time-history load function when braking begins after the entire train has entered the bridge.

[0018] When braking begins after the entire train has entered the bridge, and the time required for the train to exit the bridge as a whole is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the train to exit the bridge as a whole under the condition that braking begins after the entire train has entered the bridge is used. This time range is then extracted from the line graph of braking force versus train travel time. The function corresponding to the extracted line graph is the braking force time-history load function under the condition that braking begins after the entire train has entered the bridge.

[0019] Based on the above technical solution, the initial braking force time-history load function of the train is specifically as follows:

[0020]

[0021] Among them, F x The braking force is represented by t, the train travel time is represented by t1, and the deceleration time is represented by t1 from the start of braking until the train reaches a deceleration of 1 m / s². 2 The time required for the train to come to a complete stop is given by G, where G represents the weight of the train and t2 represents the time required for the train to come to a complete stop after it begins braking.

[0022] Based on the above technical solution, the calculation method for the time required for the entire train to exit the bridge after it has fully entered the bridge and braking begins is as follows:

[0023]

[0024] Where t0 represents the time required for the train to exit the bridge as a whole after it has fully entered the bridge and begins braking, v represents the speed of the train when it begins braking, and L represents the length of the bridge.

[0025] Based on the above technical solution, the braking force time-history load function is calculated when the train begins braking upon entering the bridge. The specific steps include:

[0026] Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted.

[0027] The time required for the entire train to enter the bridge and the time required for the entire train to exit the bridge if the train begins braking upon entering the bridge are calculated. Based on the calculated times:

[0028] The time required for the train to fully enter the bridge is less than the time from when the train begins braking until its deceleration reaches 1 m / s. 2 The time required for braking is the function corresponding to the line graph of braking force versus train travel time, which is the braking force time-history load function when the train begins braking upon entering the bridge.

[0029] The time required for the train to fully enter the bridge is greater than or equal to the time from when the train begins braking until the deceleration is 1 m / s. 2 The time required for braking is calculated according to the preset formula, which is the braking force time history load function when the train begins to brake upon entering the bridge.

[0030] When the train begins to brake as it enters the bridge, if the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after it begins to brake, then the braking force time history load function calculated according to the preset formula is the braking force time history load function when the train begins to brake as it enters the bridge.

[0031] When the train begins braking as it enters the bridge, and the time required for the entire train to exit the bridge is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the entire train to exit the bridge as it begins braking as it enters the bridge is used. This time range is then extracted from the graph of the braking force time history load function calculated according to a preset formula. The function corresponding to the extracted graph is the braking force time history load function when the train begins braking as it enters the bridge.

[0032] Based on the above technical solutions,

[0033] The calculation method for the time required for the entire train to enter the bridge is as follows:

[0034]

[0035] Where t1′ represents the time required for the entire train to enter the bridge;

[0036] The calculation method for the time required for the train to exit the bridge as a whole when it begins braking upon entering the bridge is as follows:

[0037]

[0038] Among them, t 01 This indicates the time required for the entire train to exit the bridge if it begins braking upon entering the bridge, where l represents the train length.

[0039] Based on the above technical solution, the braking force time-history load function calculated according to the preset formula is as follows:

[0040]

[0041] Among them, F x t represents the braking force, and t represents the train's travel time.

[0042] Based on the above technical solution, the step of obtaining the train braking force time-history load function by comparing the calculated braking force time-history load function images under the two scenarios includes the following specific steps:

[0043] The line graphs corresponding to the braking force time history load function when the train has fully entered the bridge and when braking begins are plotted in the same coordinate system and compared with the line graphs corresponding to the braking force time history load function when the train begins braking upon entering the bridge.

[0044] According to the principles of dynamics, the outermost point of the image in the coordinate system is recorded and connected by straight lines to form a new broken line graph. The function corresponding to the newly obtained broken line graph is the calculated train braking force time history load function.

[0045] The present invention provides a device for calculating the braking force of a bridge train, comprising:

[0046] The acquisition module is used to acquire information about the bridge and the train, as well as the train's speed, deceleration, and timing information during braking.

[0047] The first calculation module is used to calculate the corresponding braking force time-history load function when the train starts braking after it has fully entered the bridge.

[0048] The second calculation module is used to calculate the corresponding braking force time history load function when the train begins to brake as it enters the bridge.

[0049] The execution module is used to obtain the train braking force time-history load function by comparing the calculated braking force time-history load function images under the two scenarios.

[0050] Compared with the prior art, the advantages of this invention are as follows: by calculating the braking force time-history load function corresponding to the case where the train begins braking after it has fully entered the bridge, and calculating the braking force time-history load function corresponding to the case where the train begins braking as soon as it enters the bridge, and then comparing the braking force time-history load function images under the two cases, the train braking force time-history load function is finally obtained, realizing the accurate calculation of the train braking force time-history load, thereby accurately and efficiently calculating the effect of the bridge structure during the train braking process, making the calculated value consistent with the actual value, and effectively ensuring the safety of the bridge structure and train operation. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a flowchart illustrating a method for calculating the braking force of a bridge train in an embodiment of the present invention.

[0053] Figure 2 The image shows the time-history load function of the braking force when braking begins after the train has fully entered the bridge, as shown in the example.

[0054] Figure 3The example shows the time-history load function graph of the braking force when the train begins to brake upon entering the bridge.

[0055] Figure 4 This is the final calculated train braking force time-history load function image in the example. Detailed Implementation

[0056] This invention provides a method for calculating the braking force of a train on a bridge. It calculates the braking force time-history load function when braking begins after the train has fully entered the bridge, and also calculates the braking force time-history load function when braking begins upon entering the bridge. The graphs of the braking force time-history load functions in both cases are then compared to obtain the final train braking force time-history load function. This method achieves accurate calculation of the train braking force time-history load, thereby accurately and efficiently calculating the effect on the bridge structure during train braking, ensuring that the calculated value matches the actual value, and effectively ensuring the safety of the bridge structure and train operation. This invention also provides a corresponding device for calculating the braking force of a train on a bridge.

[0057] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0058] See Figure 1 As shown in the figure, the method for calculating the braking force of a bridge train provided by an embodiment of the present invention specifically includes the following steps:

[0059] S1: Obtain bridge and train information, as well as train braking information, deceleration information, and timing information;

[0060] In this invention, information about the bridge and the train, as well as the train's speed, deceleration, and timing during braking, is obtained. Specifically, the bridge length L, train length l, train weight G, the train's initial braking speed v, and the average deceleration during braking (in practice, this value is 0.8 m / s²) are acquired. 2 After the train begins braking, the deceleration reaches 1 m / s². 2 The time t1 required for the train to come to a stop after it begins braking, and the time t2 required for the train to come to a stop after it begins braking.

[0061] S2: Calculate the braking force time-history load function when the train starts braking after it has fully entered the bridge;

[0062] In this invention, the calculation of the braking force time-history load function under the condition that the train begins braking after it has fully entered the bridge includes the following steps:

[0063] S201: Based on the initial braking force time-history load function determined from the train information, draw a line graph showing the relationship between braking force and train travel time;

[0064] S202: Calculate the time required for the entire train to exit the bridge after braking begins once all trains have entered the bridge, and based on this time:

[0065] When braking begins after the entire train has entered the bridge, and the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after braking begins, then the function corresponding to the line graph of braking force versus train travel time is the braking force time-history load function when braking begins after the entire train has entered the bridge.

[0066] When braking begins after the entire train has entered the bridge, and the time required for the train to exit the bridge as a whole is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the train to exit the bridge as a whole under the condition that braking begins after the entire train has entered the bridge is used. This time range is then extracted from the line graph of braking force versus train travel time. The function corresponding to the extracted line graph is the braking force time-history load function under the condition that braking begins after the entire train has entered the bridge.

[0067] In this invention, the initial braking force time-history load function of the train is specifically (for ease of subsequent description, the following formula is denoted as Equation 1):

[0068]

[0069] Among them, F x The braking force is represented by t, the train travel time is represented by t1, and the deceleration time is represented by t1 from the start of braking until the train reaches a deceleration of 1 m / s². 2 The time required for the train to come to a complete stop is given by G, where G represents the weight of the train and t2 represents the time required for the train to come to a complete stop after it begins braking.

[0070] In this invention, the calculation method for the time required for the entire train to exit the bridge after braking has fully entered the bridge is as follows (for ease of subsequent description, the following formula is denoted as Formula 2):

[0071]

[0072] Where t0 represents the time required for the entire train to exit the bridge after it has fully entered the bridge and braking begins, v represents the train's speed at the start of braking, and L represents the bridge length.

[0073] First, based on the initial braking force time-history load function of the train, as shown in Equation 1, a line graph of the braking force versus the train's travel time is plotted according to Equation 1. Then, the time t0 required for the entire train to exit the bridge after it has fully entered the bridge and begins braking is calculated according to Equation 2. When t0 ≥ t2, the line graph determined by Equation 1 is the braking force time-history load function after the train has fully entered the bridge and begins braking. When t0 < t2, the time range from 0 to t0 is used to extract the line graph determined by Equation 1, and the function corresponding to the extracted line segment is the braking force time-history load function after the train has fully entered the bridge and begins braking.

[0074] S3: Calculate the braking force time-history load function when the train begins braking upon entering the bridge;

[0075] In this invention, the calculation of the braking force time-history load function when the train begins braking upon entering the bridge includes the following steps:

[0076] S301: Based on the initial braking force time-history load function determined from the train information, draw a line graph showing the relationship between braking force and train travel time;

[0077] S302: Calculate the time required for the entire train to enter the bridge, and the time required for the entire train to exit the bridge if the train begins braking upon entering the bridge, and based on the calculated times:

[0078] The time required for the train to fully enter the bridge is less than the time from when the train begins braking until its deceleration reaches 1 m / s. 2 The time required for braking is the function corresponding to the line graph of braking force versus train travel time, which is the braking force time-history load function when the train begins braking upon entering the bridge.

[0079] The time required for the train to fully enter the bridge is greater than or equal to the time from when the train begins braking until the deceleration is 1 m / s. 2 The time required for braking is calculated according to the preset formula, which is the braking force time history load function when the train begins to brake upon entering the bridge.

[0080] When the train begins to brake as it enters the bridge, if the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after it begins to brake, then the braking force time history load function calculated according to the preset formula is the braking force time history load function when the train begins to brake as it enters the bridge.

[0081] When the time required for the whole train to leave the bridge when braking starts when the train enters the bridge is less than the time required for the train to come to a stop after braking starts, the time range corresponding to the time required for the whole train to leave the bridge when braking starts when the train enters the bridge is adopted, and it is intercepted in the image of the braking force time-history load function calculated according to the preset formula. The function corresponding to the intercepted image is the braking force time-history load function when braking starts when the train enters the bridge.

[0082] In the present invention, the calculation method for the time required for the whole train to enter the bridge is (for the convenience of subsequent description, the following formula is denoted as Formula 3):

[0083]

[0084] where t1' represents the time required for the whole train to enter the bridge;

[0085] In the present invention, the braking force time-history load function calculated according to the preset formula is (for the convenience of subsequent description, the following formula is denoted as Formula 4):

[0086]

[0087] where F x represents the braking force, and t represents the train running time.

[0088] In the present invention, the calculation method for the time required for the whole train to leave the bridge when braking starts when the train enters the bridge is (for the convenience of subsequent description, the following formula is denoted as Formula 5):

[0089]

[0090] where t 01 represents the time required for the whole train to leave the bridge when braking starts when the train enters the bridge, and l represents the train length.

[0091] That is, first calculate the time t1' required for the whole train to enter the bridge according to Formula 3; when t1' < t1, the braking force time-history load function when braking starts when the train enters the bridge is as shown in Formula 1; when t1' ≥ t1, the braking force time-history load function when braking starts when the train enters the bridge is as shown in Formula 4;

[0092] Then calculate the time t 01 required for the whole train to leave the bridge when braking starts when the train enters the bridge according to Formula 3 01 ; when t 01 ≥ t2, the braking force time-history load function when braking starts when the train enters the bridge is as shown in Formula 4; when t 01 <t2, use the time history from 0 to t 01The range is intercepted in the broken line graph determined by Equation 4. The function corresponding to the intercepted graph is the braking force time history load function when the train begins to brake upon entering the bridge.

[0093] S4: Based on the comparison of the time-history load function images of the braking force under the two calculated conditions, the time-history load function of the train braking force is obtained.

[0094] In this invention, the train braking force time-history load function is obtained by comparing the calculated braking force time-history load function images under two different scenarios. The specific steps include:

[0095] S401: Plot the line graph of the braking force time history load function when the train has fully entered the bridge and the line graph of the braking force time history load function when the train begins to brake upon entering the bridge in the same coordinate system and compare them.

[0096] S402: According to the principle of dynamics, the outermost point of the image in the coordinate system is recorded and connected by straight lines to form a new broken line graph. The function corresponding to the newly obtained broken line graph is the calculated train braking force time history load function.

[0097] The principle behind the bridge-train braking force calculation method of this invention is as follows: During train braking, the braking force is directly proportional to the deceleration. As time progresses, the deceleration gradually increases. By recording the time relationship between train deceleration and deceleration, the time-history load curve of the train braking force can be plotted. Combining the train's entry and exit times on the bridge, the time-history load curves of the braking force at two different entry times are determined. Based on the principle of dynamics: for the same load magnitude, the shorter the impact time, the greater the structural dynamic effect. The outermost points of the two braking force time-history load curves are recorded, and connected by a straight line to form a new broken line graph, which becomes the train braking force time-history load. The train braking force time-history load is input into the bridge structure. Considering the bearing friction effect and damper effect, the "dynamic time-history method" is used for calculation, achieving accurate calculation of the train braking force's effect on the bridge structure and ensuring the safety of both the bridge and train operation.

[0098] The following example illustrates the method for calculating the braking force of a bridge train according to the present invention.

[0099] Take, for example, a train crossing a bridge 1428m long. The train length l = 550m, the train weight G = 35200kN, the train speed during braking v = 250km / h, and the average deceleration is 0.8m / s². 2 The train deceleration at time t1 = 6 seconds after braking is 1 m / s². 2 The train comes to a complete stop at t2 = 86.8s, with a deceleration of 1.3 m / s². 2 .

[0100] For a train that enters the bridge at a constant speed and then begins braking, the braking force F at t1 = 6s can be calculated according to Equation 1. x =3520kN; at t2=86.8s, the braking force F x =4576kN, draw the time history load line graph of braking force as follows Figure 2 As shown. According to Equation 2, the train's departure time from the bridge is calculated to be t0 = 23.8s. Therefore, t0 < t2. Using 0 to 23.8s... Figure 2 Extract from the middle, the extracted segment is Figure 2 The solid line graph in the figure represents the braking force time-history load function when the train begins braking after it has fully entered the bridge.

[0101] As the train begins braking upon entering the bridge, with the entire train body inside, the time t1′ is calculated to be 8.3s according to Equation 3. Since t1′ ≥ t1, the braking force F at t1′ = 8.3s is calculated according to Equation 4. x =3550kN; at t2=86.8s, the braking force F x =4576kN, draw the time history load line graph of braking force as follows Figure 3 As shown. The time t when the train leaves the bridge is calculated according to Equation 5. 01 =35.9s. Using 0~35.9s in Figure 3 Extract from the middle, the extracted segment is Figure 3 The solid line graph in the figure represents the braking force time-history load function when the train begins to brake upon entering the bridge.

[0102] Will Figure 2 Hehe Figure 3 Compare the time-history load-time graphs of the determined braking force. Record the outermost point of the graph, specifically at time t1 = 6s, and the braking force F. x =3520kN; braking force F at time t1′=8.3s. x = 3550kN; time t 01 = 35.9s, braking force F x = 3910kN. Connect the outermost points with straight lines to form a new broken line graph, which represents the time-history load of the train's braking force, as shown below. Figure 4 As shown.

[0103] Will Figure 4The time-history load of the train braking force is input into the bridge structure. Considering the bearing friction effect and damper effect, the "dynamic time-history method" is used for calculation. The beam end displacement is 7mm and the bridge tower bending moment is 15050kN.m, which agrees well with the measured values. However, the "static method" is used to calculate the effect of the train braking force on the structure. A braking force of 3520kN is directly applied to the structure, resulting in a beam end displacement of 21mm and a bridge tower bending moment of 10500kN.m. It can be seen that the results differ significantly from those obtained by the "dynamic time-history method". Therefore, this invention achieves accurate calculation of the effect of train braking force on bridge structure, ensuring the safety of bridge and train operation.

[0104] The bridge-train braking force calculation method of this invention calculates the braking force time-history load function when the train begins braking after it has fully entered the bridge, and the braking force time-history load function when the train begins braking upon entering the bridge. The method then compares the images of the braking force time-history load functions in both cases to obtain the final train braking force time-history load function. This achieves accurate calculation of the train braking force time-history load, thereby accurately and efficiently calculating the effect of the bridge structure during train braking, ensuring that the calculated value matches the actual value, and effectively guaranteeing the safety of the bridge structure and train operation.

[0105] In one possible implementation, the present invention also provides a readable storage medium located in a PLC (Programmable Logic Controller) controller. The readable storage medium stores a computer program that, when executed by a processor, implements the steps of the bridge train braking force calculation method described below:

[0106] Obtain information about bridges and trains, as well as speed, deceleration, and timing information during train braking;

[0107] Calculate the braking force time-history load function when braking begins after the train has fully entered the bridge.

[0108] Calculate the braking force time-history load function when the train begins braking as it enters the bridge.

[0109] By comparing the calculated braking force time-history load function images under the two scenarios, the train braking force time-history load function is obtained.

[0110] Storage media may be any combination of one or more computer-readable media. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. Computer-readable storage media may be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0111] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of transmitting, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless, wireline, optical fiber, RF, etc., or any suitable combination thereof.

[0112] Computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages—such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0113] The present invention provides a bridge train braking force calculation device, which includes an acquisition module, a first calculation module, a second calculation module and an execution module.

[0114] The acquisition module is used to acquire bridge and train information, as well as the train's speed, deceleration, and timing information during braking; the first calculation module is used to calculate the corresponding braking force time-history load function when the train begins braking after it has fully entered the bridge; the second calculation module is used to calculate the corresponding braking force time-history load function when the train begins braking upon entering the bridge; the execution module is used to obtain the train braking force time-history load function by comparing the calculated braking force time-history load function images under the two scenarios.

[0115] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

[0116] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

Claims

1. A method for calculating the braking force of a train on a bridge, characterized in that, Specifically, the following steps are included: Obtain information about bridges and trains, as well as speed, deceleration, and timing information during train braking; Calculate the braking force time-history load function when braking begins after the train has fully entered the bridge. Calculate the braking force time-history load function when the train begins braking as it enters the bridge. Based on the comparison of the calculated braking force time-history load function images under the two scenarios, the train braking force time-history load function is obtained. The step of obtaining the train braking force time-history load function by comparing the calculated braking force time-history load function images under the two scenarios includes the following specific steps: The line graphs corresponding to the braking force time history load function when the train has fully entered the bridge and when braking begins are plotted in the same coordinate system and compared with the line graphs corresponding to the braking force time history load function when the train begins braking upon entering the bridge. According to the principle of dynamics, the outermost point of the image in the coordinate system is recorded and connected by straight lines to form a new broken line graph. The function corresponding to the newly obtained broken line graph is the calculated train braking force time history load function. The specific steps for calculating the braking force time-history load function under the condition that the train has fully entered the bridge and begins braking include: Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted. Calculate the time required for the entire train to exit the bridge after braking begins once it has fully entered the bridge, and based on this time: When braking begins after the entire train has entered the bridge, and the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after braking begins, then the function corresponding to the line graph of braking force versus train travel time is the braking force time-history load function when braking begins after the entire train has entered the bridge. When braking begins after the entire train has entered the bridge, and the time required for the train to exit the bridge as a whole is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the train to exit the bridge as a whole is used. This range is then extracted from the line graph of braking force versus train travel time. The function corresponding to the extracted line graph is the braking force time-history load function under the condition that braking begins after the entire train has entered the bridge. The specific steps for calculating the braking force time-history load function when the train begins braking upon entering the bridge include: Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted. The time required for the entire train to enter the bridge and the time required for the entire train to exit the bridge if the train begins braking upon entering the bridge are calculated. Based on the calculated times: The time required for the train to fully enter the bridge is less than the time from when the train begins braking until its deceleration reaches 1 m / s. 2 The time required for braking is the function corresponding to the line graph of braking force versus train travel time, which is the braking force time-history load function when the train begins braking upon entering the bridge. The time required for the train to fully enter the bridge is greater than or equal to the time from when the train begins braking until the deceleration is 1 m / s. 2 The time required for braking is calculated according to the preset formula, which is the braking force time history load function when the train begins to brake upon entering the bridge. When the train begins to brake as it enters the bridge, if the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after it begins to brake, then the braking force time history load function calculated according to the preset formula is the braking force time history load function when the train begins to brake as it enters the bridge. When the train begins braking as it enters the bridge, and the time required for the entire train to exit the bridge is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the entire train to exit the bridge as it begins braking as it enters the bridge is used. This time range is then extracted from the graph of the braking force time history load function calculated according to a preset formula. The function corresponding to the extracted graph is the braking force time history load function when the train begins braking as it enters the bridge.

2. The method for calculating the braking force of a bridge train as described in claim 1, characterized in that, The acquisition of bridge and train information, as well as train braking speed, deceleration, and timing information, specifically includes: Obtain the bridge length, train length, train weight, train speed at the start of braking, average deceleration during braking, and the deceleration rate from the start of braking until it reaches 1 m / s². 2 The time required for the train to come to a complete stop after it begins braking, and the time required for the train to come to a complete stop after it begins braking.

3. The method for calculating the braking force of a bridge train as described in claim 2, characterized in that, The initial braking force time-history load function of the train is specifically as follows: in, Indicates braking force. Indicates the train's travel time. This indicates that the train's deceleration rate is 1 m / s² after it begins braking. 2 The time required Indicates the weight of the train. This indicates the time required for the train to come to a complete stop after it begins braking.

4. The method for calculating the braking force of a bridge train as described in claim 3, characterized in that, The calculation method for the time required for the entire train to exit the bridge after braking has fully entered the bridge is as follows: in, This indicates the time required for the entire train to exit the bridge after braking has begun once it has fully entered the bridge. This indicates the speed at which the train begins to brake. Indicates the length of the bridge.

5. The method for calculating the braking force of a bridge train as described in claim 4, characterized in that: The calculation method for the time required for the entire train to enter the bridge is as follows: in, This indicates the time required for the entire train to enter the bridge; The calculation method for the time required for the train to exit the bridge as a whole when it begins braking upon entering the bridge is as follows: in, This indicates the time required for the entire train to exit the bridge if it begins braking as it enters the bridge. Indicates the length of the train.

6. The method for calculating the braking force of a bridge train as described in claim 5, characterized in that, The braking force time-history load function calculated according to the preset formula is: in, Indicates braking force. Indicates the train's travel time.

7. A device for calculating the braking force of a bridge train, characterized in that, include: The acquisition module is used to acquire information about the bridge and the train, as well as the train's speed, deceleration, and timing information during braking. The first calculation module is used to calculate the corresponding braking force time-history load function when the train starts braking after it has fully entered the bridge. The second calculation module is used to calculate the corresponding braking force time history load function when the train begins to brake as it enters the bridge. The execution module is used to obtain the train braking force time history load function by comparing the calculated braking force time history load function images under the two scenarios. The step of obtaining the train braking force time-history load function by comparing the calculated braking force time-history load function images under the two scenarios includes the following specific steps: The line graphs corresponding to the braking force time history load function when the train has fully entered the bridge and when braking begins are plotted in the same coordinate system and compared with the line graphs corresponding to the braking force time history load function when the train begins braking upon entering the bridge. According to the principle of dynamics, the outermost point of the image in the coordinate system is recorded and connected by straight lines to form a new broken line graph. The function corresponding to the newly obtained broken line graph is the calculated train braking force time history load function. The specific steps for calculating the braking force time-history load function under the condition that the train has fully entered the bridge and begins braking include: Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted. Calculate the time required for the entire train to exit the bridge after braking begins once it has fully entered the bridge, and based on this time: When braking begins after the entire train has entered the bridge, and the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after braking begins, then the function corresponding to the line graph of braking force versus train travel time is the braking force time-history load function when braking begins after the entire train has entered the bridge. When braking begins after the entire train has entered the bridge, and the time required for the train to exit the bridge as a whole is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the train to exit the bridge as a whole is used. This range is then extracted from the line graph of braking force versus train travel time. The function corresponding to the extracted line graph is the braking force time-history load function under the condition that braking begins after the entire train has entered the bridge. The specific steps for calculating the braking force time-history load function when the train begins braking upon entering the bridge include: Based on the initial braking force time-history load function determined from the train information, a line graph showing the relationship between braking force and train travel time is plotted. The time required for the entire train to enter the bridge and the time required for the entire train to exit the bridge if the train begins braking upon entering the bridge are calculated. Based on the calculated times: The time required for the train to fully enter the bridge is less than the time from when the train begins braking until its deceleration reaches 1 m / s. 2 The time required for braking is the function corresponding to the line graph of braking force versus train travel time, which is the braking force time-history load function when the train begins braking upon entering the bridge. The time required for the train to fully enter the bridge is greater than or equal to the time from when the train begins braking until the deceleration is 1 m / s. 2 The time required for braking is calculated according to the preset formula, which is the braking force time history load function when the train begins to brake upon entering the bridge. When the train begins to brake as it enters the bridge, if the time required for the entire train to exit the bridge is greater than or equal to the time required for the train to come to a stop after it begins to brake, then the braking force time history load function calculated according to the preset formula is the braking force time history load function when the train begins to brake as it enters the bridge. When the train begins braking as it enters the bridge, and the time required for the entire train to exit the bridge is less than the time required for the train to come to a stop after braking begins, the time range corresponding to the time required for the entire train to exit the bridge as it begins braking as it enters the bridge is used. This time range is then extracted from the graph of the braking force time history load function calculated according to a preset formula. The function corresponding to the extracted graph is the braking force time history load function when the train begins braking as it enters the bridge.

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