A novel design method for vibration-isolated municipal roads with steel spring floating slabs

Abstract

The invention discloses a novel steel spring floating plate vibration isolation municipal road design method, comprising the following steps: S1. municipal road vibration test and analysis, determining the numerical calculation model of municipal road traffic vehicles; S2. determining the vibration control limit; S3. preliminarily determining the structural parameters of the floating plate vibration isolation road; S4. establishing the numerical model of the floating plate vibration isolation road; S5. static calculation of the numerical model of the floating plate vibration isolation road; dynamic calculation of the numerical model that meets the force requirements; S6. selecting sensitive buildings around the floating plate vibration isolation road for vibration evaluation; S7. using the vibration isolation effect evaluation index to verify the vibration isolation effect of the floating plate vibration isolation road that meets the vibration isolation requirements. The method can design a steel spring floating plate vibration isolation municipal road that can minimize the vibration of the municipal road under the action of automobile load, thereby ensuring that the vibration requirements of residential areas, commercial areas, cultural and educational areas and other areas adjacent to the municipal road are met.

Description

Technical Field

[0001] The invention relates to the technical field of municipal road design, in particular to a novel steel spring floating plate vibration isolation municipal road design method. Background Art

[0002] As people's living standards continue to improve, the impact of traffic vibration on the environment has attracted more and more attention, and traffic vibration has become one of the seven major public hazards in the world. At the same time, due to the rapid development of cities, urban land is becoming increasingly tight, and the distance between municipal roads and urban buildings is getting smaller and smaller, with the shortest distance even being only a few meters. The vibration of municipal traffic will have a significant adverse effect on the safety of nearby buildings or the comfort of people in nearby buildings.

[0003] In order to deal with the adverse effects of municipal traffic vibration on the safety of nearby buildings or the comfort of people in nearby buildings, vibration isolation technology is currently commonly used for vibration isolation. Currently, the commonly used vibration isolation technology means include ground vibration barrier isolation, such as street tree-drainage ditch-porous wave damping plate combined vibration isolation barrier, pile-filled vibration isolation ditch, assembled vibration isolation ditch with wave damping blocks, etc., but this vibration isolation method is difficult to apply to municipal roads close to buildings; building foundation vibration isolation, that is, setting a vibration isolation layer on the foundation of the building (generally using seismic isolation bearings), this vibration isolation method will greatly increase the cost of the building project and increase the difficulty of subsequent maintenance and repair. Since the steel spring floating plate can be controlled from the vibration source transmission process, it is guaranteed to have a good vibration isolation effect, and it has the advantages of low natural frequency (3~5Hz) and vibration isolation of up to 15~25dB. It has been widely used in rail transit vibration isolation and has recently begun to be used in municipal road vibration reduction. The range of municipal traffic load excitation frequency is 10~40Hz, while the range of the fundamental frequency of the steel spring floating plate is 3~5Hz, which is less than Times the municipal traffic load excitation frequency, and applying the steel spring floating plate to municipal road vibration isolation can theoretically ensure a good vibration isolation effect.

[0004] However, at present, there is a lack of a complete and feasible set of quantitative analysis integrated control technology for the vibration control design of steel spring floating plate vibration isolation municipal roads. The vibration isolation scheme is designed only by scientific experiments, which lacks universality and is difficult to apply on a large scale. If the design is based on existing experience, the design scheme is likely to fail to achieve the expected vibration isolation effect, which will affect the human comfort of nearby buildings and even bring safety hazards. Some of them need to be reworked or redesigned, resulting in a lot of unnecessary expenses. In order to solve the above problems, it is necessary to consider the universality of the calculation method and ensure that the calculation method is effective for steel spring floating plate vibration isolation municipal roads. Summary of the invention

[0005] In view of the lack of a complete and feasible integrated control technology for quantitative analysis in the current municipal road vibration control design, the present invention proposes a new steel spring floating plate vibration isolation municipal road design method, which can minimize the vibration of municipal roads under the action of automobile loads, thereby ensuring that the vibration requirements of residential areas, commercial areas, cultural and educational areas and other areas adjacent to the municipal roads are met.

[0006] In order to achieve the above-mentioned purpose, the present invention proposes a five-stage design method for a steel spring floating plate vibration isolation road design, which is applied to vibration control of municipal roads. The technical scheme is as follows:

[0007] A novel steel spring floating plate vibration isolation municipal road design method comprises the following steps:

[0008] S1. Select a municipal road with the same or similar traffic vehicle load factor as the target floating plate vibration isolation road for vibration testing to obtain measured vibration data of the municipal road; determine a numerical calculation model of municipal road traffic vehicles based on the obtained measured vibration data of the municipal road;

[0009] S2. Determine the vibration control limit according to the vibration control requirements of different areas;

[0010] S3. Determine the structural parameter range of the floating slab vibration isolation road;

[0011] S4. Selecting structural parameters within the structural parameter range, and establishing a numerical model of the floating plate vibration isolation road for the structural parameters of the floating plate vibration isolation road;

[0012] S5. Perform static calculation on the numerical model of the floating plate vibration isolation road established in step S4 to determine whether the static calculation result meets the force requirements. If so, proceed to the next step. If not, perform preliminary optimization on the structural parameters of the floating plate vibration isolation road and return to step S4. Input the numerical model that meets the force requirements into the numerical calculation model of municipal road traffic vehicles obtained in step S1 to perform dynamic calculation to obtain the vibration response of the road surface near the floating plate vibration isolation road.

[0013] S6. Select sensitive buildings around the floating plate vibration isolation road, use the road surface vibration response obtained in step S5 as excitation to calculate the vibration inside the sensitive building, and evaluate the calculated vibration to determine whether the vibration inside the sensitive building after vibration isolation meets the specification. If it meets the specification, proceed to the next step. If it does not meet the specification, further optimize the structural parameters of the floating plate vibration isolation road and return to step S4.

[0014] S7. For the floating plate vibration isolation road that meets the vibration isolation requirements, the vibration isolation effect is verified by using the vibration isolation effect evaluation index, and it is determined whether the calculated vibration isolation effect evaluation index value is lower than the vibration control limit determined in step S2. If it is lower than the vibration control limit determined in step S2, the floating plate vibration isolation road meets the vibration isolation requirements and the design is terminated. If it is not lower than the vibration control limit determined in step S2, the floating plate vibration isolation road does not meet the vibration isolation requirements, and the structural parameters of the floating plate vibration isolation road are further optimized, and the process returns to step S4.

[0015] Furthermore, in step S1, the determination of the numerical calculation model of municipal road traffic vehicles specifically includes the following steps: performing spectral analysis on the measured vibration data of the municipal road to obtain the municipal road vibration power spectrum, and then using the trigonometric series method to simulate the obtained municipal road power spectrum, and applying it to the moving force to obtain the numerical calculation model of municipal road traffic vehicles.

[0016] Furthermore, the step S3 specifically includes:

[0017] S31. Determine the length, width and thickness of the floating slab vibration isolation road through orthogonal test and finite element analysis;

[0018] S32. Simplify the steel spring floating plate vibration isolation road into a simply supported beam, establish a finite element model of the floating plate road, use permanent action and 0.5 variable action as static loads, and calculate the range of steel spring stiffness;

[0019] S33. Consider the steel spring floating plate as a single degree of freedom system and calculate the range of the steel spring spacing based on the fundamental frequency range.

[0020] Furthermore, in step S32, the range of the initially set steel spring stiffness is calculated in the following specific calculation method:

[0021] Calculate the maximum displacement value of the floating plate vibration isolation road under static load, and consult the urban bridge specifications to obtain the maximum allowable displacement value;

[0022] According to the maximum displacement value and the maximum allowable displacement value of the floating plate vibration isolation road, the deformation of the floating plate vibration isolation road caused by the spring is calculated according to the following formula:

[0023] y g =-(y max -y al )(1)

[0024] In the formula, y g is the mid-span deflection of the floating slab road, y max is the maximum displacement of the floating slab vibration isolation road under static load, y al The maximum displacement allowed for the floating slab road;

[0025] The mid-span deflection of the floating slab road can be obtained by the following formula:

[0026]

[0027] Where: y g is the mid-span deflection of the floating slab road, F is the steel spring reaction force, l is the length of the floating slab road, E is the elastic modulus of concrete, and I is the section inertia moment;

[0028] Combining equations (1) and (2), the steel spring reaction force is obtained; based on the steel spring reaction force and the maximum allowable displacement value, the threshold of the steel spring stiffness is calculated according to the following equation, and the range of the steel spring stiffness is set according to the threshold of the steel spring stiffness:

[0029]

[0030] Where: k0 is the stiffness of the steel spring, F is the reaction force of the steel spring, y al It is the maximum allowable displacement value of the floating slab vibration isolation road.

[0031] Furthermore, in step S32, the floating slab road finite element model is established by using a floating slab plate unit and a spring damping unit for a vibration isolator.

[0032] Further, in step S33, the base frequency range is based on the base frequency needs to be less than The traffic load excitation frequency is set at multiples of the traffic load excitation frequency.

[0033] Furthermore, in step S33, the range of the steel spring spacing is calculated in the following specific calculation method:

[0034] Using the fundamental frequency range, the range of the total spring stiffness can be found by the following formula:

[0035]

[0036] Where: f is the fundamental frequency, K is the total spring stiffness, and M is the mass of the concrete slab;

[0037] Using the range of the total spring stiffness and the steel spring stiffness selected from the range of the steel spring stiffness, the range of the number of steel springs is calculated by the following formula;

[0038] K=nk1(5)

[0039] Where: K is the total spring stiffness, n is the number of steel springs, k1 is the steel spring stiffness;

[0040] Using the range of the floating plate road length, floating plate road width and the number of steel springs, the range of the spring spacing is calculated by the following formula:

[0041]

[0042] Where: l g is the spring spacing, a is the length of the floating plate road, b is the width of the floating plate road, and n0 is the number of steel springs initially set;

[0043] Furthermore, the step S5 specifically includes:

[0044] S51. Consider the steel spring floating plate vibration isolation road as a multi-point supported concrete slab bridge structure, calculate the internal force, deformation and stress of the floating plate vibration isolation road under various action combinations according to the bridge specifications, and combine the internal force, deformation and stress using partial coefficients according to the specifications;

[0045] S52. According to the result calculated in step S51, the reinforcement design is performed according to the basic combination of the ultimate limit state of bearing capacity;

[0046] S53. Determine whether the result obtained in step S51 meets the force requirements. If it meets the force requirements described in step S43, proceed to the next step. If not, perform preliminary optimization on the structural parameters of the floating slab vibration isolation road and return to step S4.

[0047] Furthermore, the force requirement is that the long-term deflection caused by the combined value of the short-term effects of the floating slab vibration isolation road is less than the limit value of the normal use limit state after eliminating the long-term deflection caused by the deadweight of the structure and the cracks caused by the combined value of the short-term effects.

[0048] Furthermore, in step S5, the power calculation is performed by transient dynamics, and the calculation formula of the transient dynamics is as follows:

[0049]

[0050] Where: M, C, K are the mass matrix, damping matrix and stiffness matrix of the floating slab road model, u, are the displacement, velocity and acceleration of the floating slab road model respectively, and F is the external input load.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The vibration control design method for a steel spring floating plate municipal road proposed in the present invention combines field test analysis with numerical simulation analysis and is designed in stages to obtain optimal structural parameters, thereby obtaining an optimal steel spring floating plate municipal road, which can minimize the vibration of the municipal road under the action of automobile loads, thereby ensuring that the vibration requirements of residential areas, commercial areas, cultural and educational areas and other areas adjacent to the municipal road are met. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1A flow chart of a steel spring floating plate vibration isolation road design method according to an embodiment of the present invention;

[0054] Figure 2 A schematic diagram of a steel spring floating plate vibration isolation road under a vehicle load according to an embodiment of the present invention;

[0055] In the figure: 1. Steel spring floating plate vibration isolation road; 2. Steel spring. DETAILED DESCRIPTION

[0056] In order to explain the technical content of the present invention in more detail, the novel steel spring floating plate vibration isolation road design method of the present invention is further described below in combination with specific embodiments and drawings of the specification, but the protection content of the present invention is not limited to the following specific embodiments. The novel steel spring floating plate vibration isolation road design method of the present invention is a steel spring floating plate vibration isolation road design method under automobile load, and it should be noted that:

[0057] ① The steel spring floating plate vibration isolation road design under automobile load of the present invention adopts a vibration control technology of staged design and implementation combining field test analysis with numerical simulation analysis;

[0058] ② Due to the differences in traffic beams, vehicle types and speeds on different road sections, it is difficult to accurately describe the dynamic load laws of municipal road traffic using purely theoretical methods. Therefore, it is necessary to develop targeted on-site testing plans.

[0059] ③ The steel spring floating plate vibration isolation road design under automobile load of the present invention is carried out on the premise of meeting the driving safety and smoothness control requirements.

[0060] Please refer to Figure 1 The novel steel spring floating plate vibration isolation municipal road design method of this embodiment includes the following steps:

[0061] Phase 1: Municipal Road Vibration Testing and Analysis

[0062] (1) According to the traffic load factors such as traffic flow, vehicle type and speed predicted by the floating plate vibration isolation municipal road, select the municipal road with the same or similar factors as the floating plate vibration isolation municipal road for vibration testing, obtain the measured vibration data of the municipal road, and determine the vibration main frequency and load model of the traffic vehicle load. Specifically, the municipal road is subjected to vibration testing by placing sensors next to the lane to obtain the measured vibration data of the municipal road. The sensors can be arranged at intervals along the length of the lane, and multiple rows can be arranged. Due to the differences in traffic beams, vehicle types and speeds in different sections, it is difficult to accurately describe the dynamic load law of traffic flow on municipal roads using purely theoretical methods. Therefore, it is necessary to formulate targeted on-site test plans based on actual conditions.

[0063] (2) The measured vibration data of municipal roads are subjected to spectral analysis to obtain the vibration power spectrum of municipal roads. The power spectrum of municipal roads is simulated by the trigonometric series method and applied to the moving force to determine the numerical calculation model of municipal road traffic vehicles, thus providing a practical excitation source for the vibration isolation calculation of steel spring floating plate municipal roads.

[0064] Phase 2: Regional Vibration Control Analysis

[0065] Research and analyze the vibration control requirements of different regions, select corresponding specifications / standards according to the vibration control requirements of different regions, use corresponding evaluation indicators, determine the vibration control limit, and provide a reference for the design of municipal road vibration control. The above specifications / standards are all well-known specifications / standards in this field. For example, when the above specifications / standards use the "Urban Area Environmental Vibration Standard", the vibration evaluation index is the vertical Z vibration level, and all types of urban areas have corresponding vertical Z vibration level standard values.

[0066] Phase 3: Parameter setting of steel spring floating plate vibration isolation road (hereinafter referred to as floating plate vibration isolation road)

[0067] (1) According to the actual needs of engineering drainage, parameter analysis is carried out through orthogonal tests and finite element analysis to find the optimal design parameters and determine the length, width and thickness of the floating slab vibration isolation road.

[0068] (2) The floating plate vibration isolation road is regarded as a simply supported beam supported at both ends. The floating plate vibration isolation road FEM model is established by using the plate unit for the floating plate and the spring damping unit for the vibration isolator. The permanent action and 0.5 variable action are used as static loads to calculate the maximum displacement value of the floating plate vibration isolation road under the static load. The maximum allowable displacement value y is obtained by consulting the bridge code. al , the maximum displacement value y al :

[0069]

[0070] Where: y al is the maximum allowable displacement value, l j To calculate the span.

[0071] In order to ensure the smoothness and comfort of driving on the floating plate vibration isolation road, the steel spring support force needs to make the floating plate vibration isolation road deform as follows:

[0072] y g =-(y max -y al ) (2)

[0073] Where: y g is the mid-span deflection of simply supported floating slab road, y maxis the maximum displacement of the floating slab vibration isolation road under static load, y al It is the maximum allowable displacement value of floating slab road.

[0074] The calculation formula for the deflection of the simply supported floating slab vibration isolation road span can be obtained by the following formula:

[0075]

[0076] Where: y g is the mid-span deflection of the simply supported floating slab road, F is the steel spring reaction force, l is the length of the floating slab road, E is the elastic modulus of concrete, and I is the section moment of inertia.

[0077] Substituting the above formula (3) into formula (2), the steel spring reaction force F can be obtained.

[0078] At this point, using the steel spring reaction force and the maximum allowable displacement of the floating plate vibration isolation road, the minimum value of the steel spring stiffness can be obtained using the following formula (4), and the range of the steel spring stiffness can be set by the minimum value of the steel spring stiffness:

[0079]

[0080] Where: k0 is the stiffness of the steel spring, F is the reaction force of the steel spring, and yal is the maximum allowable displacement of the floating plate vibration isolation road.

[0081] At the same time, the steel spring stiffness can be selected in combination with the range of the steel spring stiffness and the product specifications and performance of the steel spring vibration isolator, and the initial steel spring stiffness can be set.

[0082] (3) According to the municipal road traffic load excitation frequency of 10 to 40 Hz, in order for the floating plate vibration isolation road to achieve the vibration isolation effect, the fundamental frequency must be less than times the traffic load excitation frequency, from which the upper limit of the fundamental frequency can be obtained, and thus the fundamental frequency range can be set;

[0083] Considering the steel spring floating plate as a single degree of freedom system, the fundamental frequency is calculated as follows:

[0084]

[0085] The calculation formula of the total spring stiffness is as follows:

[0086] K=nk1 (6)

[0087] Where: K is the total spring stiffness, M is the mass of the concrete slab, n is the number of steel springs, and k1 is the stiffness of the steel spring.

[0088] By using the set fundamental frequency range and the above equations (5) and (6), the range of the number of steel springs can be obtained, where the stiffness of the steel springs is determined by the above method; based on the obtained range of the number of steel springs, the selection range of the steel spring spacing can be determined according to the following formula:

[0089]

[0090] Where: l g is the spring spacing, a is the length of the floating plate road, b is the width of the floating plate road, and n0 is the number of steel springs.

[0091] Therefore, the structural parameters of the steel spring floating plate vibration isolation road are preliminarily determined. Based on the preliminarily determined structural parameters of the steel spring floating plate vibration isolation road and the actual project, specifically, the numerical model of the steel spring floating plate vibration isolation road is established in combination with the road plane dimensions and load levels.

[0092] Phase 4: Static and dynamic calculations of floating slab vibration isolation roads

[0093] (1) Perform static calculation and analysis on the established numerical model of the steel spring floating plate vibration isolation road:

[0094] The steel spring floating plate vibration isolation road is regarded as a multi-support bridge, and static calculation is performed according to the "Urban Bridge Design Code". According to the actual project, the vehicle load, temperature and other load calculation values ​​are selected to calculate the internal force, deformation and stress of the floating plate vibration isolation road under various effects. The internal force, deformation and stress of the floating plate vibration isolation road are combined according to the code using partial coefficients.

[0095] First, carry out reinforcement design according to the basic combination of ultimate bearing capacity state.

[0096] Specifically, according to the basic combination value of the internal force of the floating slab vibration isolation road, the reinforcement design of the floating slab vibration isolation road is carried out to make the resistance R greater than the effect S to meet the driving safety requirements, as shown in the following formula:

[0097] S d ≤R

[0098] Where: S d is the action combination, and R is the design value.

[0099] The stiffness and spacing of the steel springs are initially optimized based on the long-term deflection and cracks under the short-term combination of the normal service limit state. Specifically, the long-term deflection generated by the short-term effect combination value of the floating slab vibration isolation road cannot exceed the span after eliminating the long-term deflection generated by the deadweight of the structure. To meet the requirements of driving smoothness; the cracks caused by the combination value of short-term effects cannot exceed the specification limit, and the spacing and stiffness of the steel springs are optimized.

[0100] More specifically, it is necessary to determine whether the long-term deflection caused by the combined value of the short-term effect of the vibration isolation road is less than the long-term deflection caused by the self-weight of the structure when the long-term deflection exceeds the span. If yes, proceed to the next step. If no, perform preliminary optimization on the spacing and stiffness of the steel springs, return to the third stage, and establish a numerical model of the new structural parameters. The specific results can be determined by the following formula:

[0101]

[0102] Where: l l is the long-term deflection value generated by the frequently encountered combination, l j To calculate the span

[0103] And judge whether the cracks caused by the combination value of short-term effects are less than the specification limit, as shown in the following formula:

[0104] W cr ≤W s

[0105] Where: W cr To calculate the maximum crack according to the "Highway Reinforced Concrete and Prestressed Concrete Bridge and Culvert Design Code", W s is the maximum crack limit.

[0106] If yes, proceed to the next step, if not, optimize the spacing and stiffness of the steel springs and return to the third stage to establish a numerical model of the new structural parameters.

[0107] (2) Dynamic calculation: The numerical model after static calculation, that is, the data model that meets the requirements, is input into the numerical calculation model of municipal road traffic vehicles obtained in the first stage, and the road vibration response near the floating plate vibration isolation road under the action of dynamic load is calculated through transient dynamics, that is, the road vibration response after vibration isolation. Among them, the transient dynamics is determined by the following formula:

[0108]

[0109] Where: M, C, K are the mass matrix, damping matrix and stiffness matrix of the floating slab road model, u, are the displacement, velocity and acceleration of the floating slab road model respectively, and F is the external input load.

[0110] Through the above calculations, the road surface vibration response of the floating plate vibration isolation road accessory can be obtained.

[0111] Stage 5: Vibration Response of Sensitive Building Structures

[0112] Select sensitive buildings around the floating plate vibration isolation road, use the road vibration response obtained in the fourth stage as the excitation to calculate the vibration inside the sensitive building, and evaluate the calculated vibration to determine whether the vibration inside the sensitive building after vibration isolation meets the specification. If it meets the specification, proceed to the next step. If it does not meet the specification, further optimize the structural parameters of the floating plate vibration isolation road, return to the third stage, and establish a numerical model of the new structural parameters. The specification can select the vibration limit value inside the building commonly used in this field.

[0113] When the floating slab vibration isolation road and buildings are built together, a finite element (FEM) model of the sensitive building structure near the municipal road can be established, and the road surface vibration response calculated in the fourth stage can be input to calculate the vibration response of the sensitive building structure.

[0114] The consistent excitation method can be used for calculation.

[0115] Among them, the consistent excitation method uses the following dynamic equation:

[0116]

[0117] Where: y s are the absolute acceleration, velocity and displacement of the degrees of freedom at the unsupported position; M s , C s , K s are the corresponding mass, damping and stiffness; y b are the absolute acceleration, velocity and displacement of the degrees of freedom at the support respectively; M b , C b , K b are the corresponding mass, damping and stiffness;

[0118] The total structural response displacement can be divided into dynamic response displacement and pseudo-static displacement

[0119]

[0120] Where: is the dynamic reaction displacement, is the pseudo-static response displacement at the unsupported location.

[0121] According to the following formula

[0122]

[0123] The dynamic response displacement can be obtained The total structural response displacement, velocity and acceleration can be obtained from the dynamic response displacement and pseudo-static displacement.

[0124] Phase 6:

[0125] For the floating slab vibration isolation road that meets the vibration isolation requirements, the vibration isolation effect evaluation index is used to verify the vibration isolation effect, and it is judged whether the vibration isolation effect evaluation index value is lower than the vibration control limit determined above. If it is lower than the determined vibration control limit, the floating slab vibration isolation road meets the vibration isolation requirements and the design is terminated. If it is not lower than the determined vibration control limit, the floating slab vibration isolation road does not meet the vibration isolation requirements, and the structural parameters of the floating slab vibration isolation road are further optimized, and the third stage is returned to establish a numerical model of the new structural parameters.

[0126] Specifically, the vibration isolation effect evaluation indexes are frequency, maximum acceleration, Z vibration level and insertion loss. Frequency, maximum acceleration, Z vibration level and insertion loss can be determined according to the common methods or specifications in the art.

[0127] When the "Urban Environmental Area Vibration Standard" is selected in the specification, the evaluation index is the Z vibration level. The maximum acceleration of the building structure obtained by dynamic calculation is first analyzed by spectrum analysis, divided by 1 / 3 octave, and the 1 / 3 octave vibration level is calculated. Then the 1 / 3 frequency band vibration level is Z-weighted to finally obtain the Z vibration level. It is necessary to judge whether the Z vibration level after vibration isolation meets the vibration control requirements. If not, the steel spring stiffness and spacing need to be further optimized to maximize the guarantee that the vibration evaluation index value is lower than the limit value of the selected standard.

[0128] Based on the above analysis, the floating plate municipal road vibration control design method proposed in the present invention combines field test analysis with numerical simulation analysis and is designed in stages, which can ensure that the needs of municipal road vibration control are met to the greatest extent.

[0129] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. A novel steel spring floating plate vibration isolation municipal road design method, characterized in that: The steps include: S1. Select a municipal road with the same or similar traffic vehicle load factor as the target floating plate vibration isolation road for vibration testing to obtain measured vibration data of the municipal road; determine a numerical calculation model of municipal road traffic vehicles based on the obtained measured vibration data of the municipal road; S2. Determine the vibration control limit according to the vibration control requirements of different areas; S3. Determine the structural parameter range of the floating plate vibration isolation road, the step S3 specifically includes: S31. Determine the length, width and thickness of the floating slab vibration isolation road through orthogonal test and finite element analysis; S32. Simplify the steel spring floating plate vibration isolation road into a simply supported beam, establish a finite element model of the floating plate road, use permanent action and 0.5 variable action as static loads, and calculate the range of steel spring stiffness; S33. Consider the steel spring floating plate as a single degree of freedom system and calculate the range of the steel spring spacing according to the fundamental frequency range; S4. Selecting structural parameters within the structural parameter range, and establishing a numerical model of a floating plate vibration isolation road for the structural parameters; S5. Perform static calculation on the numerical model of the floating plate vibration isolation road established in step S4 to determine whether the static calculation result meets the force requirements. If so, proceed to the next step. If not, perform preliminary optimization on the structural parameters of the floating plate vibration isolation road and return to step S4. Input the numerical model that meets the force requirements into the numerical calculation model of municipal road traffic vehicles obtained in step S1 to perform dynamic calculation to obtain the vibration response of the road surface near the floating plate vibration isolation road. S6. Select sensitive buildings around the floating plate vibration isolation road, use the road surface vibration response obtained in step S5 as excitation to calculate the vibration inside the sensitive building, and evaluate the calculated vibration to determine whether the vibration inside the sensitive building after vibration isolation meets the specification. If it meets the specification, proceed to the next step. If it does not meet the specification, further optimize the structural parameters of the floating plate vibration isolation road and return to step S4. S7. For the floating plate vibration isolation road that meets the vibration isolation requirements, the vibration isolation effect is verified by using the vibration isolation effect evaluation index, and it is determined whether the calculated vibration isolation effect evaluation index value is lower than the vibration control limit determined in step S2. If it is lower than the vibration control limit determined in step S2, the floating plate vibration isolation road meets the vibration isolation requirements and the design is terminated. If it is not lower than the vibration control limit determined in step S2, the floating plate vibration isolation road does not meet the vibration isolation requirements, and the structural parameters of the floating plate vibration isolation road are further optimized, and the process returns to step S4.

2. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: In step S1, the determination of the numerical calculation model of municipal road traffic vehicles specifically includes the following steps: performing spectral analysis on the measured vibration data of the municipal road to obtain the municipal road vibration power spectrum, and then using the trigonometric series method to simulate the obtained municipal road power spectrum, and applying it to the moving force to obtain the numerical calculation model of municipal road traffic vehicles.

3. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: In step S32, the range of the steel spring stiffness is calculated in the following specific manner: Calculate the maximum displacement value of the floating plate vibration isolation road under static load, and consult the urban bridge specifications to obtain the maximum allowable displacement value; According to the maximum displacement value and the maximum allowable displacement value of the floating plate vibration isolation road, the deformation of the floating plate vibration isolation road caused by the spring is calculated according to the following formula: and g =-(and max -and al ) (1) In the formula, y g is the mid-span deflection of the floating slab road, y max is the maximum displacement of the floating slab vibration isolation road under static load, y al The maximum displacement allowed for the floating slab road; The mid-span deflection of the floating slab road can be obtained by the following formula: Where: F is the steel spring reaction force, l is the length of the floating slab road, E is the elastic modulus of concrete, and I is the section inertia moment; Combining equations (1) and (2), the steel spring reaction force is obtained; based on the steel spring reaction force and the maximum allowable displacement value, the threshold of the steel spring stiffness is calculated according to the following equation, and the range of the steel spring stiffness is set according to the threshold of the steel spring stiffness: Where: k0 is the stiffness of the steel spring, F is the reaction force of the steel spring, y al It is the maximum allowable displacement value of the floating slab vibration isolation road.

4. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: In step S32, the floating slab road finite element model is established by using a floating slab plate unit and a vibration isolator spring damping unit.

5. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: In step S33, the base frequency range is based on the base frequency needs to be less than Multiple traffic load excitation frequency setting.

6. The novel steel spring floating plate vibration isolation municipal road design method according to claim 5 is characterized in that: In step S33, the range of the steel spring spacing is calculated, and the specific calculation method is as follows: Using the fundamental frequency range, the range of the total spring stiffness can be found by the following formula: Where: f is the fundamental frequency, K is the total spring stiffness, and M is the mass of the concrete slab; Using the range of the total spring stiffness and the steel spring stiffness selected from the range of the steel spring stiffness, the range of the number of steel springs is calculated by the following formula; K=nk1 (5) Where: K is the total spring stiffness, n is the number of steel springs, k1 is the steel spring stiffness; Using the range of the floating plate road length, floating plate road width and the number of steel springs, the range of the spring spacing is calculated by the following formula: Where: l g is the spring spacing, a is the length of the floating plate road, b is the width of the floating plate road, and n0 is the spacing of the number of steel springs.

7. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: The step S5 specifically includes: S51. Consider the steel spring floating plate vibration isolation road as a multi-point supported concrete slab bridge structure, calculate the internal force, deformation and stress of the floating plate vibration isolation road under various action combinations according to the bridge specifications, and combine the internal force, deformation and stress using partial coefficients according to the specifications; S52. According to the result calculated in step S51, the reinforcement design is performed according to the basic combination of the ultimate limit state of bearing capacity; S53. Determine whether the result obtained in step S51 meets the force requirements. If it meets the force requirements described in step S43, proceed to the next step. If not, perform preliminary optimization on the structural parameters of the floating slab vibration isolation road and return to step S4.

8. The novel steel spring floating plate vibration isolation municipal road design method according to claim 1 is characterized in that: The force requirement is that the long-term deflection caused by the combined value of the short-term effects of the floating slab vibration isolation road is less than the limit value of the normal use limit state after eliminating the long-term deflection caused by the deadweight of the structure and the cracks caused by the combined value of the short-term effects.

9. The novel steel spring floating plate vibration isolation municipal road phased design method according to claim 1 is characterized in that: In step S5, the power calculation is performed by transient dynamics, and the calculation formula of the transient dynamics is as follows: Where: M, C, K are the mass matrix, damping matrix and stiffness matrix of the floating slab road model, u, are the displacement, velocity and acceleration of the floating slab road model respectively, and F is the external input load.

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