A method for evaluating the vortex-vibration sensitivity of drivers and passengers on long-span bridges

Abstract

The present invention proposes a method for evaluating the vortex-induced vibration sensitivity of drivers and passengers on large-span bridges. The method of the present invention comprises four steps: step one: establishing a vehicle-person vibration system; step two: establishing a four-wheel road surface random excitation model and a vortex-induced vibration excitation model; step three: calculating the evaluation index of driver and passenger sensitivity, comprehensively considering the vehicle vibration acceleration and the human body vibration acceleration, and evaluating the driver and passenger sensitivity from the two perspectives of vehicle and vortex-induced vibration events, so that the evaluation result is more real and reliable. Step four: evaluation of driver and passenger sensitivity. After obtaining the frequencies and modes of each order of the bridge, when vortex-induced vibration occurs, the present invention can comprehensively and quickly evaluate the driver and passenger sensitivity from the two perspectives of a single vehicle and vortex-induced vibration events.

Description

Technical Field

[0001] The invention belongs to the technical field of evaluation methods, and in particular relates to a method for evaluating the vortex-vibration sensitivity of drivers and passengers of a long-span bridge. Background Art

[0002] As key nodes of large-scale infrastructure such as high-speed railways and cross-river and cross-sea passages, the number of large-span bridges being built is increasing, and they are developing in the direction of being longer and more flexible. It is worth noting that the longer the bridge and the more flexible the structure, the more prominent its wind-induced stability problem will be, especially the vortex-induced vibration problem that has occurred frequently in recent years. Vortex-induced vibration is a kind of wind-induced limited amplitude vibration with self-excited properties that is easy to occur on large-span bridges at low wind speeds. Its relatively large amplitude and frequent occurrence will inevitably aggravate the vibration of the vehicle body, and will also reduce the safety of sight and the sensitivity of drivers and passengers. When the vibration of the vehicle body is more intense, it will cause discomfort such as nausea and vomiting to the driver and passengers. In severe cases, it will cause driving safety problems and affect the operation status of large-span bridges. Therefore, how to evaluate the sensitivity of drivers and passengers under vortex-induced vibration of large-span bridges has become an important research issue.

[0003] Driver and passenger sensitivity is directly related to the driver's workload, health and road safety. Therefore, it has always been a research hotspot at home and abroad. Most of the research focuses on the impact of daily wind, strong wind environment and road roughness on the comfort of drivers and passengers. There are few studies on the sensitivity of bridge drivers and passengers under vortex vibration, a special wind-induced vibration. In the study of driver and passenger sensitivity under vortex vibration, the acceleration in each vibration direction of the vehicle body is weighted to obtain the comprehensive weighted acceleration root mean square and use it for evaluation. The comprehensive weighted acceleration root mean square is suitable for evaluating vibrations of 0.5-80Hz, while the frequency of vortex-induced vibration is mostly less than 0.5Hz. The evaluation indicators of traditional evaluation methods are limited to a single one, and no vehicle-seat-person model is established for research. There is a certain gap between the vibration of the human body under real driving.

[0004] In view of the above problems, it is necessary to propose a method for evaluating driver and passenger sensitivity, which comprehensively considers the influence of bridge deck irregularities and vortex-induced vibration and accurately evaluates the driver and passenger sensitivity of large-span bridges under vortex-induced vibration. Summary of the invention

[0005] The purpose of the present invention is to solve the existing technical problems and propose a method for evaluating the vortex-induced vibration sensitivity of drivers and passengers on a long-span bridge. The method can evaluate the sensitivity of drivers and passengers of a single vehicle crossing the bridge, and can also evaluate the sensitivity of drivers and passengers of a certain vortex-induced vibration event as a whole.

[0006] The present invention is implemented by the following technical scheme. The present invention proposes a method for evaluating the vortex vibration sensitivity of drivers and passengers of a long-span bridge. The method specifically comprises the following steps:

[0007] Step 1: Modeling of the vehicle-human vibration system: For the vehicle model, a two-axis vehicle model is used, which is simplified into a 15-degree-of-freedom "mass-spring-damper" system. The vehicle only performs uniform linear motion, and the system's degrees of freedom along the driving direction are not considered. The system parameters are all regarded as linear parameters; each wheel has 2 degrees of freedom in the vertical and transverse directions, and the 4 wheels have a total of 8 degrees of freedom; the body has a total of 5 degrees of freedom in the vertical, transverse, nod, roll, and yaw directions; the seat in the car has a total of 2 degrees of freedom in the vertical and lateral directions; the entire system has a total of 15 degrees of freedom, and the motion equation is established according to the D'Alembert principle; for the human body model, the concentrated parameter model of the human body in a sitting position is simplified into a 9-degree-of-freedom "mass-spring-damper" vibration system, which includes 9 parts including the head and neck, upper and lower torso, internal organs, buttocks, left and right lower limbs, and left and right upper limbs. The motion equation is established based on the knowledge of dynamics, and the vehicle model and the human body model are connected by the seat;

[0008] Step 2: Road-bridge excitation modeling: For the road surface unevenness model, a single-wheel road surface excitation model is established based on the road surface power spectrum function and white noise signal. Then, considering the correlation between the left and right wheel tracks and the time lag of the front and rear wheel tracks, a four-wheel road surface excitation model is established through mathematical transformation. For the vortex-induced vibration excitation model, simple harmonic vibration is used to simulate the single-point vibration of the bridge under the vortex vibration of the main beam. Combined with the vortex vibration vibration mode, the vortex vibration excitation input model of the front and rear wheels of the vehicle at different vehicle speeds is derived.

[0009] Step 3: Calculate the evaluation index of driver and passenger perception: Calculate the comfort evaluation index of a single vehicle, obtain the vibration acceleration of each part of the human sitting model according to the vibration acceleration of the vehicle-human vibration system, perform frequency modulation processing on the vibration acceleration of each part of the sitting model with the corresponding frequency weighting function, and then perform weighted calculation through the axis weighting coefficient to obtain the comfort evaluation index of a single vehicle: the root mean square of the comprehensive weighted acceleration OVTV and the incidence of motion sickness MSI; calculate the overall comfort evaluation index of the vortex-induced vibration event. During the entire process of the vortex-induced vibration event, multiple vehicles will pass through, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, so as to evaluate the bridge driver and passenger perception under this vortex-induced vibration event;

[0010] Step 4: Evaluation of driver and passenger sensitivity: For bridges where vortex-induced vibration occurs, use the methods of steps 1 and 2 to build a model based on the pavement grade of the bridge and the frequency and amplitude of the vortex-induced vibration. Then use the method of step 3 to calculate the comfort evaluation index of a single vehicle and vortex-induced vibration events, which are used to evaluate the driver and passenger sensitivity of a single vehicle and the overall driver and passenger sensitivity of the vortex-induced vibration event, respectively.

[0011] Furthermore, in step 1, the motion equation of the vehicle-human vibration system is established according to the D'Alembert principle, with a total of 24 degrees of freedom. The vehicle vibration equation and the human body vibration equation are as follows:

[0012]

[0013]

[0014] Where [M], [C], [K] are the mass matrix, damping matrix, and stiffness matrix of the vehicle model; {y}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F} is the external excitation matrix, including road excitation and vortex-induced vibration excitation; [M m ]、[C m ]、[K m ] are the mass matrix, damping matrix and stiffness matrix of the human body model; {Z}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F m} is the external excitation matrix, which includes road surface excitation and vortex-induced vibration excitation.

[0015] Furthermore, in step 3, the vibration acceleration of the three supporting surfaces of the seat, backrest and floor in the human sitting posture model is expressed by the vibration acceleration of the established car-human vibration system:

[0016]

[0017] In the formula, a ij is the acceleration of each support surface in different directions, i = z, y, r, j = b, s, f; subscripts z and y represent the vertical and lateral directions respectively, subscript r represents the rotation direction, subscripts b, s, f represent the seat back, seat surface and floor surface respectively; represents the vertical acceleration of the upper torso and left lower limb of the human body, They represent the lateral acceleration of the vehicle center of mass, the vertical and lateral acceleration of the seat, respectively. Indicates the vehicle body roll and nodding acceleration, d s ,y s 、h s It is the longitudinal, lateral and vertical distance between the center of mass of the vehicle and the driver's position.

[0018] Furthermore, in step three, the OVTV value and MSI value are used to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge, and the AOVTV value and AMSI value are used to evaluate the overall driver and passenger sensitivity of the vortex-induced vibration event. The calculation process of the four indicators is as follows: the vibration acceleration of each part of the sitting model is frequency-modulated by the corresponding frequency weighting function and the root mean square is taken, and then the axis weighting coefficient is used for weighted calculation to obtain the comprehensive weighted acceleration root mean square OVTV and motion sickness incidence MSI two indicators to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge. During the whole process of the vortex-induced vibration event, multiple vehicles will pass by, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, and these two indicators will be used to evaluate the driver and passenger sensitivity of the vortex-induced vibration event.

[0019] Furthermore, the calculation formulas for the above four indicators are as follows:

[0020]

[0021] OVTV={∑(M ij RMS ij ) 2} 1 / 2 (5)

[0022]

[0023] MSDV T ={∑(MSDV ij ) 2} 1 / 2 (7)

[0024] MSI=K m MSDV T (8)

[0025]

[0026]

[0027] In the formula, a ω-ij (t) represents the acceleration time history of the human body vibration response after the acceleration time history aij of each support surface in different directions of the sitting model is modulated by the frequency weighting function; M ij Indicates the axis weighting coefficient of each vibration axis of the human body; MSDV T represents the motion sickness dose value; T represents the time required for a vehicle to pass through the bridge; K m is a constant; the calculated MSI is presented in the form of a percentage, indicating the proportion of people who suffer from motion sickness and vomiting; OVTV i and MSI i They represent the OVTV value and MSI value calculated when the i-th vehicle passes through the bridge.

[0028] Furthermore, K m The value is 1 / 3.

[0029] The present invention proposes an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of a method for evaluating the vortex-vibration sensitivity of drivers and passengers of a long-span bridge are implemented.

[0030] The present invention provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, the steps of a method for evaluating the vortex-vibration sensitivity of drivers and passengers of a long-span bridge are implemented.

[0031] The beneficial effects of the present invention are:

[0032] In view of the problems that the evaluation index of bridge driver and passenger sensitivity under vortex-induced vibration is limited to a single index and there is no vehicle-seat-person model, the present invention proposes a method for evaluating the driver and passenger sensitivity under vortex-induced vibration of a large-span bridge, establishes a vehicle-person vibration system, comprehensively considers the vehicle vibration acceleration and the human body vibration acceleration, evaluates the driver and passenger sensitivity from the two perspectives of vehicle and vortex-induced vibration events, and makes the evaluation results more real and reliable. After obtaining the frequencies and modes of each order of the bridge, when vortex-induced vibration occurs, the present invention can quickly evaluate the driver and passenger sensitivity from the two perspectives of a single vehicle and vortex-induced vibration events. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of a method for evaluating the driver and passenger sensitivity under vortex-induced vibration of a long-span bridge;

[0034] Figure 2 This is a 15-DOF vehicle model diagram;

[0035] Figure 3 It is a nine-degree-of-freedom human body vertical vibration model;

[0036] Figure 4 It is a graph of four rounds of random excitation curves;

[0037] Figure 5 It is the vortex-induced vibration excitation curve diagram;

[0038] Figure 6 This is a schematic diagram of a human body sitting posture model;

[0039] Figure 7 It is the acceleration time history diagram of a typical vortex-induced vibration event and the corresponding acceleration power spectrum;

[0040] Figure 8 This is a comfort evaluation diagram for a vortex-induced vibration event. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The present invention proposes a method for evaluating the vortex vibration sensitivity of drivers and passengers of a long-span bridge, and the method specifically comprises the following steps:

[0043] Step 1: Modeling of the vehicle-human vibration system: For the vehicle model, a two-axis vehicle model is used, which is simplified into a 15-degree-of-freedom "mass-spring-damper" system. The vehicle only performs uniform linear motion, and the system's degrees of freedom along the driving direction are not considered. The system parameters are all regarded as linear parameters; each wheel has 2 degrees of freedom in the vertical and transverse directions, and the 4 wheels have a total of 8 degrees of freedom; the body has a total of 5 degrees of freedom in the vertical, transverse, nod, roll, and yaw directions; the seat in the car has a total of 2 degrees of freedom in the vertical and lateral directions; the entire system has a total of 15 degrees of freedom, and the motion equation is established according to the D'Alembert principle; for the human body model, the concentrated parameter model of the human body in a sitting position is simplified into a 9-degree-of-freedom "mass-spring-damper" vibration system, which includes 9 parts including the head and neck, upper and lower torso, internal organs, buttocks (including thighs), left and right lower limbs, and left and right upper limbs. The motion equation is established based on the knowledge of dynamics, and the vehicle model and the human body model are connected by the seat;

[0044] Step 2: Road-bridge excitation modeling: For the road surface unevenness model, a single-wheel road surface excitation model is established based on the road surface power spectrum function and white noise signal. Then, considering the correlation between the left and right wheel tracks and the time lag of the front and rear wheel tracks, a four-wheel road surface excitation model is established through mathematical transformation. For the vortex-induced vibration excitation model, simple harmonic vibration is used to simulate the single-point vibration of the bridge under the vortex vibration of the main beam. Combined with the vortex vibration vibration mode, the vortex vibration excitation input model of the front and rear wheels of the vehicle at different vehicle speeds is derived.

[0045] Step 3: Calculate the evaluation index of driver and passenger perception: Calculate the comfort evaluation index of a single vehicle, obtain the vibration acceleration of each part of the human sitting model according to the vibration acceleration of the vehicle-human vibration system, perform frequency modulation processing on the vibration acceleration of each part of the sitting model with the corresponding frequency weighting function, and then perform weighted calculation through the axis weighting coefficient to obtain the comfort evaluation index of a single vehicle: the root mean square of the comprehensive weighted acceleration OVTV and the incidence of motion sickness MSI; calculate the overall comfort evaluation index of the vortex-induced vibration event. During the entire process of the vortex-induced vibration event, multiple vehicles will pass through, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, so as to evaluate the bridge driver and passenger perception under this vortex-induced vibration event;

[0046] Step 4: Evaluation of driver and passenger sensitivity: For bridges where vortex-induced vibration occurs, use the methods of steps 1 and 2 to build a model based on the pavement grade of the bridge and the frequency and amplitude of the vortex-induced vibration. Then use the method of step 3 to calculate the comfort evaluation index of a single vehicle and vortex-induced vibration events, which are used to evaluate the driver and passenger sensitivity of a single vehicle and the overall driver and passenger sensitivity of the vortex-induced vibration event, respectively.

[0047] In step 1, the motion equation of the vehicle-human vibration system is established according to the D'Alembert principle, with a total of 24 degrees of freedom. The vehicle vibration equation and the human body vibration equation are as follows:

[0048]

[0049]

[0050] Where [M], [C], [K] are the mass matrix, damping matrix, and stiffness matrix of the vehicle model; {y}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F} is the external excitation matrix, including road excitation and vortex-induced vibration excitation; [M m ]、[C m ]、[K m ] are the mass matrix, damping matrix and stiffness matrix of the human body model; {Z}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F m} is the external excitation matrix, which includes road surface excitation and vortex-induced vibration excitation.

[0051] In step 3, the vibration acceleration of the three supporting surfaces of the seat, backrest and floor in the human sitting posture model is expressed by the vibration acceleration of the established car-human vibration system:

[0052]

[0053] In the formula, a ij is the acceleration of each support surface in different directions, i = z, y, r, j = b, s, f; subscripts z and y represent the vertical and lateral directions respectively, subscript r represents the rotation direction, subscripts b, s, f represent the seat back, seat surface and floor surface respectively; represents the vertical acceleration of the upper torso and left lower limb of the human body, They represent the lateral acceleration of the vehicle center of mass, the vertical and lateral acceleration of the seat, respectively. Indicates the vehicle body roll and nodding acceleration, d s ,y s 、h s It is the longitudinal, lateral and vertical distance between the center of mass of the vehicle and the driver's position.

[0054] In step three, the OVTV value and MSI value are used to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge, and the AOVTV value and AMSI value are used to evaluate the overall driver and passenger sensitivity of the vortex-induced vibration event. The calculation process of the four indicators is as follows: the vibration acceleration of each part of the sitting model is frequency-modulated by the corresponding frequency weighting function, and the root mean square is taken. Then, the axis weighting coefficient is used for weighted calculation to obtain the comprehensive weighted acceleration root mean square OVTV and motion sickness incidence MSI indicators to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge. During the entire process of the vortex-induced vibration event, multiple vehicles will pass by, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, and these two indicators will be used to evaluate the driver and passenger sensitivity of the vortex-induced vibration event.

[0055] The calculation formulas for the above four indicators are as follows:

[0056]

[0057] OVTV={∑(M ij RMS ij ) 2} 1 / 2 (5)

[0058]

[0059] MSDV T ={∑(MSDV ij ) 2} 1 / 2 (7)

[0060] MSI=K m MSDV T (8)

[0061]

[0062]

[0063] In the formula, a ω-ij (t) represents the acceleration time history of each support surface of the sitting model in different directions. ij The acceleration time history of human vibration response after frequency modulation by frequency weighting function; M ij Indicates the axis weighting coefficient of each vibration axis of the human body; MSDV T represents the motion sickness dose value; T represents the time required for a vehicle to pass through the bridge; K m is a constant. For a group consisting of adult males and females, K m The value is 1 / 3; the calculated MSI is presented in the form of a percentage, indicating the proportion of people who suffer from motion sickness and vomiting; OVTV i and MSIi They represent the OVTV value and MSI value calculated when the i-th vehicle passes through the bridge.

[0064] Embodiment 1:

[0065] like Figure 1 As shown in the figure, a method for evaluating the driver and passenger sensitivity under vortex-induced vibration of a long-span bridge is as follows:

[0066] The first step is to establish the vehicle-human vibration system: Figure 2 and Figure 3 The model, formulas (1) and (2) are used to derive the model vibration equation. The specific forms of each term in formulas (1) and (2) are as follows:

[0067] The specific expression of each degree of freedom of the car model is as follows:

[0068]

[0069] The specific forms of the mass matrix, damping matrix, and stiffness matrix of the car model are as follows:

[0070]

[0071]

[0072] in:

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081] The specific form of the external excitation matrix of the car model is as follows:

[0082]

[0083] In the formula, m s Represents the mass of the vehicle body, m ti Represents the total mass of the vehicle's suspension and tires, m v represents the mass of the seat, k vyand k vz represents the lateral and vertical spring stiffness of the seat, c vy and c vz represents the lateral and vertical damping of the seat, k siy and k siz is the lateral and vertical spring stiffness of the wheel suspension, k tiy and k tiz represents the lateral and vertical spring stiffness of the wheel, c siy and c siz is the lateral and vertical damping of the wheel suspension, c tiy and c tiz Represents the lateral and vertical damping of the wheel; θ xz represents the nodding angle, θ yz is the roll angle, θ xy represents the yaw angle, y y and z represents the lateral and vertical displacement of the vehicle body, y vy and vz represents the lateral and vertical displacement of the seat, y tiy represents the lateral displacement of the wheel, y tiz represents the vertical displacement of the wheel, i represents the i-th wheel, i=1, 2, 3, 4. riy and riz represents the lateral and vertical excitations of the wheel due to road roughness, y viy and viz Indicates the lateral and vertical excitations of the wheels due to bridge vibration. a1 and a2 indicate the distances from the front and rear axles to the center of gravity of the vehicle body, and b1 and b2 indicate the lateral distances from the left and right wheels to the center of gravity of the vehicle body.

[0084] The specific expressions of the degrees of freedom of the human body model are as follows:

[0085] Z=[z1 z2 z3 z4 z5 z6 z7 z8 z9] T (twenty three)

[0086] The specific forms of the mass matrix, damping matrix, and stiffness matrix of the human body model are as follows:

[0087] M m =diag(m1 m2 m3 m4 m5 m6 m7 m8 m9) (24)

[0088]

[0089]

[0090] The coefficient matrix [B m ] and the incentive matrix [Q m ]The specific form is as follows:

[0091]

[0092]

[0093] Where m i (i=1,2,…,9) represent the mass of the head and neck, upper trunk, internal organs, lower trunk, buttocks (including thighs), left lower limb, right lower limb, left upper limb, and right upper limb respectively; k i 、c i is the stiffness and damping coefficient corresponding to each part, z i (i=1,2,…,9) represents the vertical displacement of each part, m s 、m v is the mass of the vehicle body and seat, k vz 、c vz is the vertical stiffness and damping of the connection between the car body and the seat; here the left and right upper limbs are placed on the steering wheel, and the excitation is replaced by the vibration response of the car body center of mass in this paper.

[0094] The second step is to establish a road-bridge excitation model: according to the road power spectrum function and the white noise signal, a single-wheel road random excitation model is simulated, as shown in formula (29); then the left and right wheel tracks are correlated, and the coherence function of the left and right wheels is shown in formula (30). Formula (31) represents the transfer function between the right wheel road white noise input W1 and W2. By fitting formula (30), the coefficients in formula (31) can be obtained; then the front and rear wheel tracks are correlated, and there is only a time lag between the front and rear wheels. The Pade approximation can be used to calculate and obtain a four-wheel road random excitation model, as shown in Figure 4 , see formula (30), formula (31) and formula (32); for the bridge excitation model, simple harmonic vibration is used to simulate the single-point vibration of the bridge under the vortex vibration of the main beam. Combined with the vortex vibration vibration mode, the vortex vibration excitation input model of the front and rear wheels of the vehicle at different vehicle speeds is derived, see formulas (35) to (37), and the typical vortex vibration excitation curve is shown in Figure 5 .

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101] f(t)=Asin(2πf v·t+θ) (35)

[0102] y f (x,t)=ψ(vt)·f(t) (36)

[0103]

[0104] Where n0 represents the reference spatial frequency (m -1 ), G q (n0) represents the road roughness coefficient (m 3 ), the value is in GB7031-86, n 00 Indicates the cut-off frequency in the road space (m -1 ), the value is 0.011, v is the vehicle speed, t d =L / v, L is the wheelbase, w(t) represents the unit white noise signal. W1, W2, W3, W4 represent the random excitation input of the road surface of the right front wheel, left front wheel, right rear wheel and left rear wheel respectively, f(t) is the vibration response of any point on the bridge, A is the vortex-induced vibration amplitude, f v is the vortex vibration frequency, θ is the phase angle, ψ(x) is the main beam frequency f v The unit mode corresponding to the vortex vibration.

[0105] The third step is to calculate the comfort indicators OVTV, MSI, AOVTV, and AMSI: First, represent the acceleration of the vehicle-human vibration system. Figure 6 The vibration accelerations in the sitting posture model are shown in formula (3); then the OVTV, MSI, AOVTV, and AMSI values ​​are calculated according to formulas (4) to (10). In formula (3), a ω-ij (t) represents the acceleration time history of each support surface of the sitting model in different directions. ij The acceleration time history of human body vibration response after frequency modulation by frequency weighting function, the frequency weighting function and axis weighted vibration coefficient and the principle of using them refer to ISO 2631-1, and the evaluation specifications of OVTV and AOVTV values ​​are shown in Table 1.

[0106] In the fourth step, for bridges where vortex-induced vibration occurs, the methods of the first and second steps are used to build a model based on the pavement grade of the bridge and the frequency, amplitude and mode of the vortex-induced vibration, and the method of the third step is used to calculate the comfort evaluation indexes of a single vehicle and a vortex-induced vibration event, which are used to evaluate the driver and passenger perception of a single vehicle and the overall driver and passenger perception of the vortex-induced vibration event, respectively; OVTV and AOVTV values ​​are suitable for evaluating the vibration comfort of 0.5-80 Hz, and the evaluation specifications are shown in Table 1; MSI and AMSI values ​​represent the percentage of people suffering from motion sickness, and are suitable for evaluating the vibration comfort of 0-0.5 Hz, and the acceleration time history diagram of a typical vortex-induced vibration event and the corresponding acceleration power spectrum are shown in Figure 7, Typical vortex-induced vibration event comfort evaluation see Figure 8 , Figure 8 Each point on the middle curve represents the OVTV and MSI values ​​calculated when the vehicle passes the bridge at the moment of vortex-induced vibration. Taking the root mean square value of the curve gives the AOVTV and AMSI values.

[0107] Table 1 Evaluation criteria for OVTV and AOVTV values

[0108]

[0109] The present invention proposes a method for evaluating the sensitivity of drivers and passengers under vortex-induced vibration of large-span bridges, establishes a vehicle-human vibration system and a four-wheel road random excitation model, comprehensively considers the vehicle vibration acceleration and the human body vibration acceleration, and evaluates the sensitivity of drivers and passengers from the two perspectives of vehicle and vortex-induced vibration events, making the evaluation results more real and reliable. After obtaining the frequencies and modes of each order of the bridge, when vortex-induced vibration occurs, the present invention can quickly and comprehensively evaluate the sensitivity of drivers and passengers from the two perspectives of a single vehicle and vortex-induced vibration events.

[0110] The present invention proposes an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of a method for evaluating the vortex-vibration sensitivity of drivers and passengers of a long-span bridge are implemented.

[0111] The present invention provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, the steps of a method for evaluating the vortex-vibration sensitivity of drivers and passengers of a long-span bridge are implemented.

[0112] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM). It should be noted that the memory of the method described in the present invention is intended to include, but is not limited to, these and any other suitable types of memory.

[0113] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, a solid state disc (SSD)).

[0114] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0115] It should be noted that the processor in the embodiment of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to perform, or the hardware and software modules in the decoding processor can be combined and performed. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0116] The above is a detailed introduction to a method for evaluating the vortex-vibration sensitivity of passengers on large-span bridges proposed in the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for evaluating the vortex vibration sensitivity of drivers and passengers on a long-span bridge, characterized in that: The method specifically comprises the following steps: Step 1: Modeling of the vehicle-human vibration system: For the vehicle model, a two-axis vehicle model is used, which is simplified into a 15-degree-of-freedom "mass-spring-damper" system. The vehicle only performs uniform linear motion, and the system's degrees of freedom along the driving direction are not considered. The system parameters are all regarded as linear parameters; each wheel has 2 degrees of freedom in the vertical and transverse directions, and the 4 wheels have a total of 8 degrees of freedom; the body has a total of 5 degrees of freedom in the vertical, transverse, nod, roll, and yaw directions; the seat in the car has a total of 2 degrees of freedom in the vertical and lateral directions; the entire system has a total of 15 degrees of freedom, and the motion equation is established according to the D'Alembert principle; for the human body model, the concentrated parameter model of the human body in a sitting position is simplified into a 9-degree-of-freedom "mass-spring-damper" vibration system, which includes 9 parts including the head and neck, upper and lower torso, internal organs, buttocks, left and right lower limbs, and left and right upper limbs. The motion equation is established based on the knowledge of dynamics, and the vehicle model and the human body model are connected by the seat; Step 2: Road-bridge excitation modeling: For the road surface unevenness model, a single-wheel road surface excitation model is established based on the road surface power spectrum function and white noise signal. The formula is: Next, consider the correlation between the left and right wheel tracks. The coherence function formula of the left and right wheels is as follows: Wherein, formula (31) represents the transfer function between the right wheel road white noise input W1 and W2, and the coefficients in formula (31) are obtained by fitting formula (30); Then consider the time lag of the front and rear wheel tracks. There is only a time lag between the front and rear wheels, which is calculated using the Pade approximation. The formula is: For the vortex-induced vibration excitation model, simple harmonic vibration is used to simulate the single-point vibration of the bridge under the vortex vibration of the main beam. Combined with the vortex vibration vibration mode, the vortex vibration excitation input model of the front and rear wheels of the vehicle at different vehicle speeds is derived; the formula is as follows: f(t)=Asin(2πf v ·t+θ) (35) y f (x,t)=ψ(vt)·f(t) (36) Where n0 represents the reference spatial frequency, G q (n0) represents the road roughness coefficient, n 00 represents the cut-off frequency in the road space, v is the vehicle speed, t d =L / v, L is the wheelbase, w(t) represents the unit white noise signal; W1, W2, W3, W4 represent the random excitation input of the road surface of the right front wheel, left front wheel, right rear wheel and left rear wheel respectively, f(t) is the vibration response of any point on the bridge, A is the vortex-induced vibration amplitude, f v is the vortex vibration frequency, θ is the phase angle, ψ(x) is the main beam frequency f v The unit mode corresponding to the vortex vibration; Step 3: Calculate the evaluation index of driver and passenger perception: Calculate the comfort evaluation index of a single vehicle, obtain the vibration acceleration of each part of the human sitting model according to the vibration acceleration of the vehicle-human vibration system, perform frequency modulation processing on the vibration acceleration of each part of the sitting model with the corresponding frequency weighting function, and then perform weighted calculation through the axis weighting coefficient to obtain the comfort evaluation index of a single vehicle: the root mean square of the comprehensive weighted acceleration OVTV and the incidence of motion sickness MSI; calculate the overall comfort evaluation index of the vortex-induced vibration event. During the entire process of the vortex-induced vibration event, multiple vehicles will pass through, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, so as to evaluate the bridge driver and passenger perception under this vortex-induced vibration event; Step 4: Evaluation of driver and passenger sensitivity: For bridges where vortex-induced vibration occurs, use the methods of steps 1 and 2 to build a model based on the pavement grade of the bridge and the frequency and amplitude of the vortex-induced vibration. Then use the method of step 3 to calculate the comfort evaluation index of a single vehicle and vortex-induced vibration events, which are used to evaluate the driver and passenger sensitivity of a single vehicle and the overall driver and passenger sensitivity of the vortex-induced vibration event, respectively.

2. The method according to claim 1, characterized in that In step 1, the motion equation of the vehicle-human vibration system is established according to the D'Alembert principle, with a total of 24 degrees of freedom. The vehicle vibration equation and the human body vibration equation are as follows: Where [M], [C], [K] are the mass matrix, damping matrix, and stiffness matrix of the vehicle model; {y}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F} is the external excitation matrix, including road excitation and vortex-induced vibration excitation; [M m ]、[C m ]、[K m ] are the mass matrix, damping matrix and stiffness matrix of the human body model; {Z}, is the displacement, velocity, and acceleration column vector of each degree of freedom of the vehicle system; {F m } is the external excitation matrix, which includes road surface excitation and vortex-induced vibration excitation.

3. The method according to claim 2, characterized in that In step 3, the vibration acceleration of the three supporting surfaces of the seat, backrest and floor in the human sitting posture model is expressed by the vibration acceleration of the established car-human vibration system: In the formula, a ij is the acceleration of each support surface in different directions, i = z, y, r, j = b, s, f; subscripts z and y represent the vertical and lateral directions respectively, subscript r represents the rotation direction, subscripts b, s, f represent the seat back, seat surface and floor surface respectively; represents the vertical acceleration of the upper torso and left lower limb of the human body, They represent the lateral acceleration of the vehicle center of mass, the vertical and lateral acceleration of the seat, respectively. Indicates the vehicle body roll and nodding acceleration, d s ,y s 、h s It is the longitudinal, lateral and vertical distance between the center of mass of the vehicle and the driver's position.

4. The method according to claim 3, characterized in that In step three, the OVTV value and MSI value are used to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge, and the AOVTV value and AMSI value are used to evaluate the overall driver and passenger sensitivity of the vortex-induced vibration event. The calculation process of the four indicators is as follows: the vibration acceleration of each part of the sitting model is frequency-modulated by the corresponding frequency weighting function, and the root mean square is taken. Then, the axis weighting coefficient is used for weighted calculation to obtain the comprehensive weighted acceleration root mean square OVTV and motion sickness incidence MSI indicators to evaluate the driver and passenger sensitivity of a single vehicle crossing a bridge. During the entire process of the vortex-induced vibration event, multiple vehicles will pass by, and the root mean square of the OVTV and MSI values ​​of these vehicles will be taken to obtain the AOVTV value and AMSI value, and these two indicators will be used to evaluate the driver and passenger sensitivity of the vortex-induced vibration event.

5. The method according to claim 4, characterized in that The calculation formulas for the above four indicators are as follows: OVTV={∑(M ij RMS ij ) 2 } 1 / 2 (5) MSDV T ={∑(MSDV ij ) 2 } 1 / 2 (7) MSI=K m MSDV T (8) In the formula, a ω-ij (t) represents the acceleration time history of the human body vibration response after the acceleration time history aij of each support surface in different directions of the sitting model is modulated by the frequency weighting function; M ij Indicates the axis weighting coefficient of each vibration axis of the human body; MSDV T represents the motion sickness dose value; T represents the time required for a vehicle to pass through the bridge; K m is a constant; the calculated MSI is presented in the form of a percentage, indicating the proportion of people who suffer from motion sickness and vomiting; OVTV i and MSI i They represent the OVTV value and MSI value calculated when the i-th vehicle passes through the bridge.

6. The method according to claim 5, characterized in that K m The value is 1 / 3.

7. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

8. A computer-readable storage medium for storing computer instructions, characterized in that: When the computer instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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