A design method for sound barriers for high-speed rail transit

Abstract

The application provides a high-speed rail traffic sound barrier design method, which comprises the following steps: equivalent noise generated by high-speed rail traffic vehicle operation to different regional combined sound source as an equivalent sound source; the equivalent sound source is regarded as a fixed sound source, the time interval of train movement is converted into the distance interval of measuring points along the length direction of the line, and the infinite long sound barrier structure type, the height of the vertical sound barrier or the enclosed area of the enclosed sound barrier which meet the emission noise standard are obtained through iterative calculation; the equivalent sound source is regarded as a moving sound source, and the sound barrier structure type, size and end extension which meet the emission noise standard are obtained through iterative calculation. The design method of the application is aimed at the sound generation characteristics of high-speed rail traffic, and the optimal design scheme of the sound barrier is comprehensively obtained from the economy, structural safety and noise reduction effect, so that the design rationality is improved and the noise reduction design requirements of high-speed rail traffic are met.

Description

Technical Field

[0001] This invention belongs to the field of acoustic design technology for sound barriers, and in particular, it is a method for accurately determining the type, height, and end length of sound barriers based on the magnitude and characteristics of noise emitted by high-speed rail transit vehicles. Background Technology

[0002] Noise barriers, as a measure to block noise propagation, are the most widely used and largest-investment projects in the field of noise reduction for rail transit. In recent years, with the speed-up tests and research of high-speed railway projects and the research and promotion of high-speed maglev transportation systems, the noise source size and environmental noise impact of future ultra-high-speed (400km / h and above) rail transit will exceed those of rail transit under current technical standards, further increasing the demand for noise reduction through sound barriers.

[0003] High-speed railways with a speed of 350 km / h primarily use 2.3m and 3.3m high vertical sound barriers on bridge sections, and 3m and 4m high vertical sound barriers on roadbed sections, to meet the daytime noise limits of 70dB(A) and nighttime noise levels at 1.2m above the ground and 30m above the track centerline on the outer side of the railway, as stipulated in the "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90). Currently, some high-speed railways have implemented fully enclosed and semi-enclosed sound barriers.

[0004] However, the higher the height of a vertical sound barrier, and the more enclosed the track due to a closed sound barrier, the greater the vehicle-induced aerodynamic load acting on the sound barrier. This increases the overall structural stiffness requirement of the sound barrier, leading to larger structural components in the design, resulting in higher investment, more complex construction processes, and higher precision requirements. Furthermore, besides increasing the height of vertical sound barriers or the enclosed area of ​​closed sound barriers to improve noise reduction, increasing the end extension of the same type and size sound barrier also increases the noise reduction effect on protected targets within the sound shadow zone. Currently, designs do not consider the impact of different protected target locations, track technical conditions (rail height, track structure, train flow, etc.), and different sound barrier heights or types on the end extension of the sound barrier (generally, sound barrier designs consider an end extension of 50m). This fails to effectively combine the noise reduction requirements at the protected target location, the structural type of the sound barrier, and the end extension, making it impossible to arrive at the optimal design solution considering economy, structural safety, and noise reduction effectiveness. Summary of the Invention

[0005] In view of this, the present invention aims to overcome the shortcomings of the above-mentioned problems in the prior art and proposes a design method for high-speed rail transit sound barriers. This method can comprehensively consider the technical conditions of high-speed rail transit lines, emission noise reduction requirements, sound barrier structural type, height of vertical sound barriers, enclosure area of ​​enclosed sound barriers, and extension of sound barrier ends, so as to achieve precise design of sound barriers and comprehensively optimize the noise reduction efficiency, economy, and structural safety of the sound barriers.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] The first aspect of this invention provides a design method for a sound barrier for high-speed rail transit, comprising the following steps:

[0008] S1: The noise generated by high-speed rail transit vehicles is equivalent to a combination of sound sources in different areas, which is used as an equivalent sound source;

[0009] S2: Using the equivalent sound source as a fixed sound source, the time interval of train movement is converted into the distance interval of measuring points along the length of the line. Through iterative calculation, the infinitely long sound barrier structure type, the height of the vertical sound barrier, or the closed area of ​​the closed sound barrier that meets the emission noise standards is obtained.

[0010] S3: Using the equivalent sound source as a moving sound source, the structural type, size, and end extension of the sound barrier that meet the emission noise standards are obtained through iterative calculation.

[0011] Furthermore, step S1 specifically includes:

[0012] Based on sound source identification, scaled-down model wind tunnel tests, or reliable numerical calculations, the sound power levels of the head car area, tail car area, and the entire vehicle surface under high-speed operation of the rail transit vehicles on the designed line are obtained. According to the sound energy proportion of different areas, the sound power levels of all areas are further divided into combined equivalent sound sources of point sound sources, line sound sources, and surface sound sources.

[0013] Furthermore, step S2 specifically includes:

[0014] The equivalent sound source determined in step S1 is used as a fixed sound source. The time interval of the moving sound source is converted into the same distance measurement point with the same interval along the length of the line. The moving speed of the sound source is multiplied by the time interval of the passing sound level and used as the distance interval of the measurement point along the length of the rail transit line.

[0015] Calculate the equivalent sound level time history curve of the sound source attenuating to the measuring point when a train passes through the line with the sound barrier. Take the peak time of the time history curve as the train passing period and calculate the exposure sound level of the train passing during this period.

[0016] Based on the train traffic flow and daytime / nighttime train flow ratio provided in the design, calculate the daytime equivalent sound level and nighttime equivalent sound level at measuring points 30m from the outer rail centerline and 1.2m above the ground, respectively;

[0017] The daytime and nighttime equivalent sound levels are compared with the standard requirements to determine whether the design requirements are met. The daytime and nighttime equivalent sound levels after setting up an infinitely long sound barrier are calculated to determine the structural type and size of the sound barrier acoustic design.

[0018] The vertical sound barrier is calculated based on a 2.3m high vertical sound barrier as the basic working condition. The height of the vertical sound barrier is incremented in 0.5m. The height of the vertical sound barrier that meets the noise emission standards is determined through iterative calculation.

[0019] The closed sound barrier is based on a 4.8m high vertical sound barrier with an equivalent height of 4.8m for the closed area of ​​a single-sided closed sound barrier. The closed area is calculated at intervals of 0.5m*L along the cross-section of the closed sound barrier. The closed area of ​​the closed sound barrier that meets the noise emission standards is calculated through iterative calculation, where L is the dimension of the sound barrier unit along the length of the line.

[0020] Furthermore, step S3 specifically includes:

[0021] The structure and dimensions of the infinitely long sound barrier that meets emission standards, the height of the vertical sound barrier, or the closed area of ​​the enclosed sound barrier, as determined in step S2, are used as the explicit structure and dimensions of the finite-length sound barrier.

[0022] The equivalent sound source determined in step S1 is defined as a moving sound source. The moving speed of the sound source is the high-speed running speed of the rail transit vehicle. Taking the extension of the sound barrier end of 50m as the benchmark and 10m as the increment of the extension of the sound barrier end, the equivalent sound level time history curve when the train passes through the line with the sound barrier is calculated. The peak time of the time history curve is taken as the train passing period, and the exposure sound level SEL2 of the train passing during this period is calculated.

[0023] Based on the train traffic flow and daytime / nighttime train flow ratio provided in the design, calculate the daytime and nighttime equivalent sound levels at measuring points 30m from the outer rail centerline and 1.2m above ground, respectively.

[0024] By comparing the daytime and nighttime equivalent sound levels with the standard requirements, the end extension of the sound barrier with a defined structure and size to meet the noise emission standards was determined through iterative calculations.

[0025] Furthermore, the vertical sound barrier is a cantilever structure with a maximum installation height of 4.3m. If the calculation results of the 4.3m high vertical sound barrier still do not meet the standards, then a closed sound barrier with a steel structure spanning the rail transit line will be adopted.

[0026] A second aspect of the present invention provides a high-speed rail transit sound barrier, which is designed using the above-described high-speed rail transit sound barrier design method.

[0027] Compared with existing technologies, the high-speed rail transit sound barrier design method of the present invention has the following advantages:

[0028] This invention first uses field measurements, model tests, or reliable calculations to accurately represent the noise generated by high-speed rail vehicles as combined sound sources in different areas. Using these determined combined sound sources as fixed sources, the time intervals of train movement are converted into distance intervals between measuring points along the track length. Iterative calculations determine the structural type of an infinitely long sound barrier that meets emission noise standards, the height of a vertical sound barrier, or the enclosed area of ​​a closed sound barrier. Then, using the combined sound sources as moving sources, iterative calculations determine the end extension of the sound barrier with a specific structural type and size. This design method, considering the sound generation characteristics of high-speed rail transit, comprehensively derives the optimal sound barrier design from the perspectives of economy, structural safety, and noise reduction effect, improving design rationality and better meeting the noise reduction design requirements of high-speed rail transit. Attached Figure Description

[0029] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0030] Figure 1 This is a flowchart of the method of the present invention;

[0031] Figure 2 This is a schematic diagram of the general structural type and height iteration increment of a vertical sound barrier under the benchmark working condition.

[0032] Figure 3 To treat the sound source as a fixed sound source, a schematic diagram is shown in which the train movement time interval is converted into the distance interval of the measuring point;

[0033] Figure 4 This diagram illustrates the general structural form and iterative increment of the closed area of ​​a closed sound barrier under the baseline working condition.

[0034] Figure 5 A schematic diagram showing the reference design and increment of the extension at the end of the sound barrier;

[0035] Figure 6 This is the equivalent sound source for Example 1;

[0036] Figure 7 Example 1 shows an infinitely long, 2.3m high vertical sound barrier. The equivalent sound level time history curve and the diagram of Dt1 are shown for the measuring point 30m from the outer track centerline and 1.2m above the ground when a train passes through it.

[0037] Figure 8 The equivalent sound level time history curve and the diagram of Dt2 are shown for the sound barrier of Example 1 with different end extensions. The measuring points are 30m from the outer rail centerline and 1.2m above the ground. Detailed Implementation

[0038] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] Example 1: See Figure 1 The design method of the high-speed rail transit sound barrier of the present invention mainly includes: (S1) equivalent sound source of high-speed rail transit vehicle operation; (S2) defining stationary sound source, iteratively calculating and determining the infinitely long sound barrier structure type, vertical sound barrier height or closed sound barrier area that meets the noise reduction requirements; (S3) defining moving sound source, iteratively calculating the end extension of the sound barrier with specific structure type and size that meets the noise reduction requirements.

[0043] S1: Based on sound source identification, scaled-down model wind tunnel tests, or reliable numerical calculations, the sound power levels of the head car area, tail car area, and the entire vehicle surface under high-speed operation of the rail transit vehicles on the designed line are obtained. According to the sound energy proportion of different areas, the sound power levels of all areas are further divided into a combination of point sound sources, line sound sources, and surface sound sources as the input items of the acoustic design method of the sound barrier of this invention.

[0044] See Figure 2 Based on the technical conditions such as the rail surface height, vehicle speed, and line structure of the rail transit line section, a fixed equivalent sound source is used as the fixed sound source. The moving sound source time interval (DT) is converted into measuring points at the same distance from the center line of the outer rail along the same interval (DL) along the length of the line. The sound source moving speed (V) is multiplied by the adopted passing sound level time interval as the distance interval of the measuring point along the length of the rail transit line. The relationship between the time interval and the distance interval of the measuring point is shown in Equation 1.

[0045] DT = DL / V (Equation 1)

[0046] Calculate the time history curve of the equivalent sound level attenuated from the sound source to the measuring point when a train passes over the line with the sound barrier, and take the peak value L of the time history curve as the value. max1 -20dB(A) is the intercept duration for the train's passage period Dt1(T2-T1), L A (t1) represents the equivalent sound level at each time point. The exposure sound level SEL1 of the train passing during this period is calculated as shown in Equation 2.

[0047]

[0048] Using the train traffic logarithm (a) and day-night train traffic ratio (θ) provided in the design, calculate the daytime equivalent sound level L at measuring points 30m from the outer rail centerline and 1.2m above ground. Aeq,昼1 Nighttime equivalent sound level L Aeq,夜1 As shown in Equations 3 and 4 respectively.

[0049]

[0050]

[0051] L Aeq,昼1 L Aeq,夜1 The daytime noise level of 70 dB(A) and the nighttime noise level of 60 dB(A) in the "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90) were respectively used as the criteria for meeting the design requirements. The daytime and nighttime equivalent sound levels after setting up an infinitely long sound barrier were calculated to determine the structural type and size of the sound barrier acoustic design.

[0052] See Figure 3The vertical sound barrier is calculated based on a 2.3m high vertical sound barrier as the basic working condition. The height of the vertical sound barrier is incremented in 0.5m increments. The height of the vertical sound barrier that meets the noise emission standards is determined through iterative calculation. The vertical sound barrier is a cantilever structure. Based on structural reliability considerations, the maximum height is 4.3m. If the calculation results of the 4.3m high vertical sound barrier still do not meet the standards, then a closed sound barrier with a steel structure spanning the rail transit line must be used.

[0053] See Figure 4 The closed sound barrier is based on a 4.8m high vertical sound barrier with an equivalent height of 4.8m for the closed area of ​​a single-sided closed sound barrier. The closed area is calculated by iterative calculation at intervals of 0.5m*L (where L is the dimension of the sound barrier unit along the length of the line) along the cross-section of the closed sound barrier to meet the noise emission standards.

[0054] See Figure 5 The structure and dimensions of a finite-length sound barrier are defined by the structure type of the infinitely long sound barrier that meets emission standards, the height of a vertical sound barrier, or the closed area of ​​a closed sound barrier. The equivalent sound source is defined as a moving sound source with a moving speed of V, which is the high-speed operating speed of a rail transit vehicle. The iterative calculation is based on a sound barrier end extension of 50m and an increment of 10m.

[0055] Calculate the time history curve of the equivalent sound level attenuated from the sound source to the measuring point when a train passes over the line with the sound barrier, and take the peak value L of the time history curve as the value. max2 The -20dB(A) threshold is taken for the train passage period Dt2(T4-T3). The exposure sound level SEL2, L during this period is calculated. A (t2) represents the equivalent sound level at each time point, as shown in Equation 5.

[0056]

[0057] Using the train traffic flow (a) and daytime / nighttime train flow ratio (θ) provided in the design, calculate the daytime equivalent sound level L at measuring points 30m from the outer rail centerline and 1.2m above ground. Aeq,昼2 Nighttime equivalent sound level L Aeq,夜2 As shown in Equations 6 and 7 respectively.

[0058]

[0059] The two calculation results were compared with the daytime 70dB(A) and nighttime 60dB(A) standard requirements of "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90). The end extension of the sound barrier with a clear structural type and size to meet the noise emission standard was determined by iterative calculation.

[0060] The precise acoustic design method for high-speed rail transit of the present invention will be described in detail below with reference to specific embodiments.

[0061] The high-speed maglev line is designed for a speed of 450 km / h. The track surface height in the noise protection section is 10 m. The line type is a bridge. The daily train flow is 167 pairs, and the day-night train flow ratio is 8:1.

[0062] (1) See Figure 6 Through sound source identification tests on operating maglev trains, individual sound sources in different areas of the train body surface and surrounding area when the high-speed maglev train passes at high speed were located. By processing the test results, sound sources in similar areas were merged and equivalent to line sound sources or point sound sources according to the characteristics of the sound sources. The sound sources generated by the 3-car high-speed maglev train running at a speed of 450km / h were equivalent to 5 sound sources in the vicinity of the train body area. The sound source types, sizes (mainly for line sound sources), quantities and sound power levels are shown in Table 1.

[0063] Table 1

[0064]

[0065]

[0066] (2) Using the equivalent sound source in Table 1 as a fixed sound source, the train movement time interval DT is 0.008s. The time interval is converted into measuring points at the same interval along the length of the line, 30m from the center line of the outer rail and 1.2m above the ground. According to Equation 1, the distance DL between adjacent measuring points is 1m.

[0067] (3-1) Based on the track height of 10m and the line type of bridge, after calculating and setting an infinitely long 2.3m high vertical sound barrier, Table 1 shows the equivalent sound level attenuated to all measuring points. According to the conversion relationship between the measuring point interval DL and the test specimen interval DT, the sound level at different measuring points is converted into the equivalent sound level at different times of a single measuring point, and the time history curve of the sound source attenuating to the equivalent sound level at the measuring point when the high-speed maglev train passes at a speed of 450km / h is obtained.

[0068] (3-2) See Figure 7 From the equivalent sound level time history curve, L can be obtained. max1 If it is 92.2dB(A), then with L max1 Using -20dB(A) or 72.2dB(A) as the baseline, the time period T1 to T2 of the train passage is determined by extracting the time history curve. According to Equation 2, the high-speed maglev passage period SEL1 is calculated to be 92.5dB(A).

[0069] (3-3) With a train flow of 167 pairs and a daytime-night train flow ratio of 8:1, after setting up an infinitely long, 2.3m high vertical sound barrier, calculate the daytime equivalent sound level L at measuring points 30m from the outer rail centerline and 1.2m above the ground according to Equations 3 and 4. Aeq,昼1 The equivalent sound level at night is 69.7 dB(A), L. Aeq,夜1 It is 63.6 dB(A).

[0070] (3-4) In accordance with the standard requirements of 70 dB(A) during the day and 60 dB(A) at night in the "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90), after setting up an infinitely long 2.3m high vertical sound barrier, the daytime requirements are met under the technical conditions of this embodiment, but the nighttime requirements are exceeded by 3.6 dB(A).

[0071] (3-5) Set up an infinitely long, 2.8m high (2.3m high vertical sound barrier with a height increment of 0.5m) vertical sound barrier, repeat steps (3-1) to (3-4), and calculate the daytime equivalent sound level L at the measuring point 30m from the center line of the outer track and 1.2m above the ground. Aeq,昼1 The equivalent sound level at night is 69.4 dB(A), L. Aeq,夜1 The value is 63.4 dB(A), which meets the standard requirements during the day but exceeds the standard requirements by 3.4 dB(A) at night.

[0072] (3-6) Set up an infinitely long, 3.3m high (2.8m high vertical sound barrier with a height increment of 0.5m) vertical sound barrier, repeat steps (3-1) to (3-4), and calculate the daytime equivalent sound level L at the measuring point 30m from the center line of the outer track and 1.2m above the ground. Aeq,昼1 The equivalent sound level at night is 67.1 dB(A), L. Aeq,夜1 The value is 61.1 dB(A), which meets the standard requirements during the day but exceeds the standard requirements by 1.1 dB(A) at night.

[0073] (3-7) Set up an infinitely long, 3.8m high (3.3m high vertical sound barrier with a height increment of 0.5m) vertical sound barrier, repeat steps (3-1) to (3-4), and calculate the daytime equivalent sound level L at the measuring point 30m from the center line of the outer track and 1.2m above the ground. Aeq,昼1 The equivalent sound level at night is 66.1 dB(A), L. Aeq,夜1 The value is 60.1 dB(A), which meets the standard requirements during the day but exceeds the standard requirements by 0.1 dB(A) at night.

[0074] (3-8) Set up an infinitely long, 4.3m high (3.8m high vertical sound barrier with a height increment of 0.5m) vertical sound barrier, repeat steps (3-1) to (3-4), and calculate the daytime equivalent sound level L at the measuring point 30m from the center line of the outer track and 1.2m above the ground.Aeq,昼1 The equivalent sound level at night is 64.2 dB(A), L. Aeq,夜1 The value is 58.2 dB(A), which meets the standard requirements both day and night.

[0075] (3-9) If an infinitely long, 4.3m high vertical sound barrier is installed, and the daytime and nighttime equivalent sound levels at the measuring points 30m from the outer track centerline and 1.2m above the ground do not meet the standard requirements, then a closed sound barrier needs to be installed. The closed sound barrier is based on a 4.8m high vertical sound barrier with an equivalent height of the closed area of ​​a single-sided closed sound barrier. The closed area is calculated by repeating steps (3-1) to (3-4) iteratively to determine the closed area of ​​the closed sound barrier that meets the noise emission standards.

[0076] (4-1) Define the equivalent sound source determined in step (1) as a moving sound source with a moving speed of 450 km / h.

[0077] (4-2) Based on the track height of 10m and the track type of bridge, after calculating and setting a 4.3m high vertical sound barrier with an end extension of 50m, the equivalent sound level at the sound source attenuation point is calculated according to the specific location of the sound source at each moment. The equivalent sound level time history curve at the measuring point is obtained.

[0078] (4-3) See Figure 8 From the equivalent sound level time history curve, L can be obtained. max2 If it is 86.4dB(A), then with L max2 Using -20dB(A), or 66.4dB(A), as the baseline, the time period T3 to T4 of the train passage is determined by extracting the time history curve. According to Equation 5, the high-speed maglev passage period SEL2 is calculated to be 88.4dB(A).

[0079] (4-4) With a train flow of 167 pairs and a daytime-night train flow ratio of 8:1, after setting up a 4.3m high vertical sound barrier with an end extension of 50m, calculate the daytime equivalent sound level L at measuring points 50m from the end of the sound barrier, 30m from the center line of the outer rail, and 1.2m above the ground according to Equations 6 and 7. Aeq,昼1 The equivalent sound level at night is 65.5 dB(A). Aeq,夜1 It is 59.5 dB(A).

[0080] (4-5) In accordance with the standard requirements of 70 dB(A) during the day and 60 dB(A) at night in the "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90), after setting up a 4.3m high vertical sound barrier with an end extension of 50m, the technical conditions of this embodiment meet the standard requirements for both day and night.

[0081] (5) For the high-speed maglev line with a design speed of 450km / h, the track surface height in the noise protection section is 10m, the line type is a bridge, the daily train flow is 167 pairs, and the day-night train flow ratio is 8:1. The design requires the installation of 4.3m high vertical sound barriers with an end extension of 50m to meet the requirements of the standard "Railway Boundary Noise Limits and Measurement Methods" (GB12525-90).

[0082] Example 2: The present invention provides a high-speed rail transit sound barrier, which is designed using the above-described high-speed rail transit sound barrier design method.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-speed rail transit sound barrier design method, characterized in that: Comprise the following steps: S1: the noise generated by high-speed rail transit vehicle operation is equivalent to the combined sound source of different areas as the equivalent sound source; S2: the equivalent sound source is regarded as a fixed sound source, the time interval of train movement is converted into the distance interval of measuring point along the length direction of line, and the structure type of infinite sound barrier, the height of vertical sound barrier or the enclosed area of enclosed sound barrier meeting the emission noise standard is obtained through iterative calculation; Specifically, it comprises: The equivalent sound source determined by step S1 is regarded as a fixed sound source, the time interval of moving sound source is converted into the same distance measuring point at the same interval along the length direction of line, and the moving speed of sound source is multiplied by the time interval of passing sound level to obtain the distance interval of measuring point along the length direction of rail transit line; The equivalent sound level time history curve of sound source attenuation to measuring point when train passes through the sound barrier line is calculated, the time length of peak value of time history curve is intercepted as the train passing period, and the train passing exposure sound level in the period is calculated; The diurnal equivalent sound level and the night equivalent sound level of the measuring point at the center line of the outer rail 30m and above the ground 1.2m are calculated respectively according to the train flow provided by the design and the day-night train flow ratio; The diurnal equivalent sound level and the night equivalent sound level are compared with the standard requirements respectively as the judgment condition meeting the design requirements, the structure type and size of the sound barrier acoustic design are determined by calculating the diurnal and night equivalent sound levels after setting the infinite sound barrier; The vertical sound barrier takes 2.3m high vertical sound barrier as the iterative calculation basic working condition, the height of vertical sound barrier takes 0.5m as the increment, and the height of vertical sound barrier meeting the noise emission standard is obtained through iterative calculation; The enclosed area interval of enclosed sound barrier section is 0.5m*L, and the enclosed area of enclosed sound barrier meeting the noise emission standard is obtained through iterative calculation, wherein L is the size of sound barrier unit along the length direction of line; S3: the equivalent sound source is regarded as a moving sound source, and the structure type, size and end extension of the sound barrier meeting the emission noise standard are obtained through iterative calculation; Specifically, it comprises: The structure and size of finite length sound barrier are determined by taking the structure type of sound barrier meeting the emission standard, the height of vertical sound barrier or the enclosed area of enclosed sound barrier determined by step S2 as the infinite length sound barrier; The equivalent sound source determined by step S1 is defined as a moving sound source, the moving speed of sound source is the high speed running speed of rail transit vehicle, the end extension of sound barrier is 50m as the reference, and 10m is the increment of end extension of sound barrier, the equivalent sound level time history curve of train passing through the sound barrier line is calculated, the time length of peak value of time history curve is intercepted as the train passing period, and the train passing exposure sound level SEL2 in the period is calculated; The diurnal equivalent sound level and the night equivalent sound level of the measuring point at the center line of the outer rail 30m and above the ground 1.2m are calculated respectively according to the train flow provided by the design and the day-night train flow ratio, The diurnal equivalent sound level and the night equivalent sound level are compared with the standard requirements respectively, and the end extension of the sound barrier meeting the noise emission standard is determined through iterative calculation.

2. The method for designing a sound barrier of high-speed rail transit according to claim 1, characterized in that: The step S1 specifically comprises: According to the sound source identification, the scale model wind tunnel test or reliable numerical calculation, the sound power level of the head car area, the tail car area and the whole vehicle surface of the design line rail transit vehicle under high-speed running state is obtained, and according to the sound energy proportion of different areas, the sound power level of the whole area is further divided into the combination equivalent sound source of point sound source, line sound source and surface sound source.

3. The method for designing a sound barrier of high-speed rail transit according to claim 1, characterized in that: The vertical sound barrier is a cantilever structure, and the highest setting height is 4.3 m. If the calculation result of the 4.3 m high vertical sound barrier still does not meet the standard, a closed sound barrier of steel structure crossing the rail transit line is adopted.

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