JP2003214941A - Noise predicting method by soundproof wall and program for making computer execute the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve prediction accuracy by bringing a noise predicted value, especially its change in the vicinity of a boundary, closer to an actual value. <P>SOLUTION: All energy Eall,i of noise on a sound receiving point 11 during a sound source 10 passes through a roadway and energy E2,i on an upper soundproof wall are calculated. From the energy Eall,i and E2,i, the energy E6,i=Eall, i-E2,i blocked by a soundproof wall part is derived. Among the energy, the energy of the noise at an end face of the soundproof wall and at an opening part are calculated and corrected with diffraction effect. A total noise level is predicted by adding a noise level at the upper soundproof wall to a correction amount. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise predicting method in the case where there is a noise source for shielding noise generated from a certain noise source on the road, for example, a vehicle traveling on the road, and a program causing a computer to execute the method. It is about.

[0002]

2. Description of the Related Art In recent years, as a measure against serious traffic noise, a soundproof wall has been installed on a highway to enhance the soundproof effect. As a method of verifying such a soundproof effect, for example, there is a method of capturing the sound itself as energy and predicting and calculating this energy by simulation. As this prediction method, a prediction calculation model ASJModel 1998 of road traffic noise (described in Acoustical Society of Japan, Vol. 55, No. 4, published on April 1, 1999) is known.

The characteristics of this predictive calculation model are LAe
It is based on an energy-based calculation model with q as the noise evaluation quantity. In the road traffic noise prediction calculation method based on the noise evaluation amount LAeq, the temporal change (unit pattern) of noise at the prediction point (sound receiving point) when one vehicle travels on the target road, and its The basis is to find the time integral value. The specific procedure is shown below.

(1) First, assume a target road, for example, a curved road as shown in FIG. 16 for generalization, and divide this road into several sections. In FIG. 16, 10 is a sound source (automobile) and 11 is a sound receiving point.

(2) Here, one divided section Δli (i
Is an arbitrary integer), select the middle point as the representative point,
The sound propagation from that section to a predetermined sound receiving point is calculated.
In that case, the sound power Pi (or power level LW, i) radiated by the sound source in the section is calculated. In order to add the contributions from all the divided sections in terms of energy, the squared sound pressure pi ² is considered as an amount proportional to the acoustic energy density at the sound receiving point.

(3) The time integrated value Ei [Pa ² · s] of the squared sound pressure at the sound receiving point during the time Δti [s] in which the sound source exists in the i-th section is obtained. Ei = pi ² · Δti = pi ² · (Δli / vi) where Δli: length of the i-th section [m] vi: traveling speed of the vehicle at the i-th [m / s]

(4) Obtain the total amount (exposure amount) E [Pa ² · s] of the time-integrated value of the squared sound pressure at the sound receiving point while the sound source is passing through the target road.

[0008]

[Equation 1] However, Vi: traveling speed of the vehicle in the i-th section
[km / h], Vi = 3.6vi Note that FIG. 17 is a unit pattern showing the time integrated value Ei of the squared sound pressure and the total amount E thereof.

The level-displayed amount of this equation (1) is the single noise exposure level LPE. LPE = 10log ₁₀ where (E / E0), E0: in the amount of standard of ^{exposure, E0 = p0 2 · 1 [} Pa 2 ·
s] p0: reference sound pressure, p0 = 20 μPa

Next, a method of calculating the unit pattern by the B method will be described. (1) The time variation (unit pattern) LPA, i of the A characteristic sound pressure level observed at a predetermined sound receiving point when one vehicle travels alone on the road is obtained.

LPA, i = LWA-8-20 log ₁₀ ri + ΔLd + ΔLg (2) where, LPA, i: A characteristic sound pressure level [dB] LWA: A characteristic power level [dB] of vehicle running noise, large size In the case of a car, LWA = 53.2 + 30log ₁₀ V In the case of a small car, LWA = 46.7 + 30log ₁₀ V ri: Distance from sound source point to prediction point [m] ΔLd: Correction amount due to diffraction effect [dB], sound source, Path difference δ obtained from the geometrical arrangement of diffraction points and expected points
(However, if the condition that the sound source can be seen through is minus), if the road difference δ ≧ 1, ΔLd = −20−10log ₁₀ δ0 ≦ δ <1, ΔLd = −5 + (− 15) / [ln (1 + √2 )] ・ S
inh ⁻¹ (| δ | ^0.414 ) −0.0537 ≦ δ <0 ΔLd = −5 − (− 15) / [ln (1 + √2)] · s
inh ⁻¹ (| δ | ^0.414 ) δ <-0.0537 ΔLd = 0 (3) ΔLg: A correction amount [dB] due to the surface effect of the road,
Since the ground surface in this case is assumed to be concrete or asphalt, ΔLg = 0.

(2) Energy integration (single noise exposure level) LAE and equivalent noise level LAeq of the unit pattern are calculated.

The single noise exposure level of the A characteristic sound pressure is calculated by the following equation.

[Equation 2]

Then, in consideration of the traffic volume per hour N [vehicles / 3600s], the equivalent noise level LAeq, which is the energy average level at that time, is obtained.

[Equation 3] The above calculation is performed for each vehicle type and each lane, and the resultant level composite value is calculated as LAeq of the noise from the entire road at the sound receiving point.

The A characteristic sound pressure level LPA and the single-shot noise exposure level LAE are required to be of two types, that is, a blank without a sound barrier and a continuous arrangement (infinite length). By installing a wall (for example, a soundproof wall of 5 [m] or more), traffic noise was dealt with. However, in general roads, installing a high noise barrier is as follows.

1. Access obstacles such as branch roads due to the installation of soundproof walls 2. 2. Infringement of sunshine right on roadside residents 3. Radio interference 4. It was difficult to install a high soundproof wall such as an expressway on this general road because there was a concern that the visibility would be restricted.

Therefore, in general roads, a low-rise sound barrier (for example, 0.8 [m] in height) whose height is significantly lower than that of a sound barrier of a highway is installed to prevent noise and to be predetermined. The concept of arranging the opening of is attracting attention. However, there are few research materials that clearly show the soundproof effect of this low-layer sound barrier, and among the few studies, for example, as shown in the unit pattern of FIG. 18, the A characteristic sound pressure level LPA is shown.
There is a method in which the temporal change of (see equation (1)) is obtained and the single noise exposure level LAE based on the A characteristic sound pressure level is calculated.

In the noise prediction method by the noise barrier in this research, the A characteristic sound pressure level in the case of the blank without the noise barrier is used to calculate the single noise level of the opening,
Further, in order to calculate the single noise level of the soundproof wall, the A characteristic sound pressure level when the soundproof walls are continuously arranged is used. In addition, here, the height of the soundproof wall is 0.8 [m],
The width of the opening is set to 6 [m] and the sound receiving point is set to the center of the opening.

[0019]

However, in this conventional noise predicting method, as described above, the blank case and the continuous arrangement are used in a short-circuited manner, and therefore, as shown in FIG. Since the noise level suddenly changes near the boundary, there is a problem that there is a high possibility that the noise level will greatly differ from the actual value.

The present invention has been made in view of the above problems, and it is possible to improve the prediction accuracy by making the noise prediction value close to the actual value, and especially making the change near the boundary close to the actual value. An object of the present invention is to provide a noise prediction method by a wall and a program that causes a computer to execute the method.

[0021]

In order to achieve the above object, according to the present invention, in a noise predicting method using a soundproof wall for soundproofing noise generated from a certain noise source on a road, the noise level when the soundproof wall is not present. And a second calculation step of calculating a noise level that wraps around from the upper side of the soundproof wall when the soundproof wall is present, and a third calculation step of calculating a noise level dammed by the soundproof wall. Step, a fourth calculation step of calculating the noise level of the soundproof wall end face from the noise level calculated in the third calculation step, and an opening of the soundproof wall from the noise level calculated in the third calculation step Of the noise level calculated in the second, fourth and fifth calculation steps, and the calculated combined energy is integrated over time. Prediction step and noise prediction method according to the sound barrier, characterized in that it comprises a predicting a single noise exposure levels from those with is provided.

According to the present invention, the noise level at the end face of the noise barrier and the noise level is calculated from the noise level energy dammed by the noise barrier, and the noise level at the upper side of the noise barrier is added to the single noise exposure. Since the level is predicted, the predicted noise value can be approximated to the actual value, and in particular, the change near the boundary can be approximated to the actual value for prediction.

According to the second aspect of the present invention, the first aspect
A program for causing a computer to execute the noise prediction method according to the noise barrier described in.

This program describes a calculation processing method for noise prediction of a noise barrier, and the description language and description method are not particularly limited, and source code, binary code, execution format, etc. It doesn't matter the format.
Further, this program is not necessarily limited to a single configuration, and may be distributed and configured as a plurality of modules or libraries, and achieves its calculation function in cooperation with an individual program such as OS. Including things.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a noise prediction method by a noise barrier and a program for causing a computer to execute the method according to the present invention will be described below with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 is a flow chart of a calculation procedure for explaining Embodiment 1 of a noise prediction method using a soundproof wall according to the present invention, and FIG. 2 is a unit pattern according to the present invention. . The unit pattern of FIG. 2 is calculated under the same setting conditions as the unit pattern shown in FIG.

In this embodiment, first, before performing the prediction calculation, the soundproof wall information which is the information about the installation distance and the height indicating the start and end points of the soundproof wall, and whether the expressway or the general road is wide are shown. Position, speed of a sound source (automobile) that is a certain noise source, sound source information that is information about the vehicle type and number of lanes, sound receiving point information that is the position of the sound receiving point, and opening that is the opening position and width of the opening. Enter information (steps 101-10)
4).

Here, for example, as shown in FIG. 3 and FIG.
When the sound source is present in the i-th section for a time Δti, the energy received by the sound receiving point is E1, i [Pa ² · s], the energy above the noise barrier is E2, i, and the energy at the end surface of the noise barrier is E3. , i, E4, i and the energy of the opening of the soundproof wall are E5, i, it can be expressed as E1, i = E2, i + E3, i + E4, i + E5, i.

Eall, i corresponds to the amount of energy received by the sound receiving point when there is no sound barrier.

Eall, i is

[Equation 4] Can be calculated (step 105).

E2, i is the energy of the sound coming from above the soundproof wall,

[Equation 5] (Steps 106 and 107), where ri is
The straight line distance between the sound source and the sound receiving point is shown.

The E3, i, E4, i, E5, i correspond to a part of the energy E6, i of the sound shielded by the soundproof wall when the soundproof wall is installed for an infinite length. This E6, i becomes E6, i = Eall, i-E2, i (step 108).

Here, E3, i and E4, i are energy of sound in which a part of E6, i wraps around the end surface of the soundproof wall, and E3, i
5, i is the energy of sound emitted from the opening.
Next, the soundproof wall end surface energies E3, i, E4, i and the opening energy E5, i are obtained (steps 109, 11).
0).

First, in the case of E3, i, suppose now E
When the schematic diagram in the case of 3, i is described in the plan view of FIG. 5, the path difference δ of the sound coming from the end surface of the soundproof wall is δ = (e + d) −r0 (8) or δ = r0− (e + d) … (9). Here, when the sound source 10 is viewed from the sound receiving point, the time when the sound source 10 is located on the back surface of the soundproof wall is Equation (8),
Equation (9) is used when the sound source 10 is not located behind the sound barrier.

Diffraction correction amount ΔLd from δ using equation (3)
And E3, i is calculated from the following equation.

[Equation 6] Similarly, E4, i is also calculated from the following equation by obtaining the diffraction correction amount ΔLd from δ using equation (3).

[Equation 7]

Next, the energy E5, i emitted from the opening is obtained using the plan views of FIGS. Here, the case of a + b <c + d and the case of a + b> c + d will be described separately. First, in the case of a + b <c + d, the energy of the opening is calculated by considering the soundproof wall model of FIGS. 7 and 8.

In the soundproof wall model of FIG. 7, the path difference δ
Is δ = a + b−r0 (12) or δ = r0− (a + b) (13) Here, when the sound source 10 is viewed from the sound receiving point, when the sound source 10 is located behind the soundproof wall 13. Expression (12), and when the sound source 10 is not located behind the soundproof wall 13, the expression (1
3) is used.

Diffraction correction amount ΔLd2 from δ using equation (3)
And E5, i (1) is calculated from the following equation.

[Equation 8]

In the soundproof wall model of FIG. 8, the path difference δ
Is δ = c + d−r0 (15) or δ = r0− (c + d) (16) Here, when the sound source 10 is viewed from the sound receiving point, when the sound source 10 is located behind the soundproof wall 14. Expression (15), and when the sound source 10 is not located on the back surface of the soundproof wall 14, the expression (1
6) is used.

Diffraction correction amount ΔLd3 from δ using equation (3)
And E5, i (2) is calculated from the following equation.

[Equation 9]

Next, the energy emitted from the opening is calculated from the difference between the equations (14) and (17). E5, i = E5, i (1) -E5, i (2) (18) Becomes

Next, in the case of a + b> c + d, the energy of the opening is calculated by considering the soundproof wall model of FIGS. 9 and 10.

In the soundproof wall model of FIG. 9, the path difference δ
Is δ = c + d−r0 (19) or δ = r0− (c + d) (20) Here, when the sound source 10 is viewed from the sound receiving point, when the sound source 10 is located behind the soundproof wall 14. Equation (19), and when the sound source 10 is not located behind the soundproof wall 14,
0) is used.

Diffraction correction amount ΔLd2 from δ using equation (3)
And E5, i (1) is calculated from the following equation.

[Equation 10]

In the soundproof wall model of FIG. 10, the road difference δ
Is δ = a + b−r0 (22) or δ = r0− (a + b) (23) Here, when the sound source 10 is viewed from the sound receiving point, when the sound source 10 is located behind the soundproof wall 13. Expression (22), and when the sound source 10 is not located on the back surface of the soundproof wall 13, the expression (2)
3) is used.

Diffraction correction amount ΔLd3 from δ using equation (3)
And E5, i (2) is calculated from the following equation.

[Equation 11]

Next, the energy emitted from the opening is obtained from the difference between the equations (21) and (24). E5, i = E5, i (1) -E5, i (2) (25) Becomes E5, i obtained by any one of these methods becomes the acoustic energy emitted from the opening.

Next, the obtained energies E2, i, E
The sum of 3, i, E4, i, E5, i is calculated, and after time integration is performed within t1 to t2, it is converted into logarithm (steps 111 to 113). That is, the energy sum E1, i
Becomes E1, i = E2, i + E3, i + E4, i + E5, i (26), and by converting this logarithmically, the noise prediction value (single noise exposure level) LAE is

[Equation 12] Is calculated as follows (step 114).

The present inventors conducted the following experiments in order to verify the accuracy of the noise prediction method for the noise barrier according to the present invention.

As the conditions of the experiment, as shown in the front view and the top view of FIGS. The sound receiving points 17 to 19 are 1.2 [m] high from the ground,
It is installed on the opposite side of the road from the low-rise sound barrier 15 to 5 [m], and the sound receiving point 17 is located at the center of the opening, the sound receiving point 18 is located at 3 [m] from the center of the opening, and the sound receiving point is located at the sound receiving point. 19 was installed at a position 6 [m] from the center of the opening. 2. Sound source 10 is a small car, soundproof wall 15 to 2.13
The vehicle was run on the lines of [m] and 5.38 [m] at a speed of 40 [km] per hour. The former is the near lane and the latter is the far lane. 3. The low-rise sound barrier 15 has a total length of 50 [m] and has an opening 16
Is installed in the center, and the height of the soundproof wall is 0.8 [m],
It was set to 1.2 [m] and 6 [m], respectively. 4. The opening width was 6 [m], and the lengths of the low-layer soundproof walls 15 at both ends were set to 22 [m] each.

The present inventors set the soundproof wall height to each of the above-mentioned three types (the soundproof wall height is 0.8 [m], 1.2 [m], 6 [m]) and set the field height. While conducting an experiment, calculation of a simulation by the noise prediction method of the present invention,
Simulation calculations were performed by the conventional method, and the results shown in Tables 1 to 3 below were obtained.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3] As can be seen from this verification result, the insertion loss indicating the attenuation amount of the noise barrier is calculated as a result of the noise prediction method of the present invention, and the calculated value is closer to the experimental value than the conventional method. It was a suitable and suitable result.

Further, based on the result of this simulation, unit patterns of the present invention and the conventional method in which the sound receiving point is at the center of the opening are prepared and shown in FIGS. 2, 13 and 18. 2 and 18, as already described,
For convenience of explanation, the unit pattern obtained by the present invention and the unit pattern obtained by the conventional method under the same conditions are shown separately. In addition, FIG.
The unit patterns of the present invention and the conventional method under the same conditions are shown in the same figure.

As can be seen from these results, the unit pattern according to the present invention has a gentler slope, particularly near the boundary between the soundproof wall and the opening, than the unit pattern according to the conventional method which exhibits a drastic change in noise level. While showing, the noise level will change. That is, in the unit pattern according to the present invention, when the sound source 10 is running on a soundproof wall, it is largely attenuated by the soundproofing effect of the soundproof wall, and has almost the same level as that with the wall. Then, when the sound source 10 gradually approaches the end surface of the soundproof wall, the soundproof effect of the wall weakens, and the energy amount at the opening 16 becomes almost the same as in the state without the wall. Also, when the edge of the protective wall approaches, it is affected by the soundproof effect of the wall,
When the vehicle is in the same state as when there is a wall, and when traveling on the wall, the amount of energy is almost the same as when there is a wall, so the value that is closest to the actual value is displayed, improving prediction accuracy. To do.

As described above, in this embodiment, the soundproof wall upper side energy, the soundproof wall end surface energy and the opening energy are calculated, and the energy sum is calculated and integrated over time to obtain the noise prediction value. As compared with the unit pattern shown in FIG. 18, as shown in the unit pattern of FIG. 2, the noise prediction value can be brought closer to the actual value, and particularly the change near the boundary is brought closer to the actual value to improve the prediction accuracy. Can be planned.

(Embodiment 2) FIG. 14 is a diagram showing the structure of a soundproof wall having a plurality of openings. FIG. 15 is a flowchart of the calculation procedure in the second embodiment of the noise prediction method of the present invention used for calculating the noise from the noise barrier having the configuration of FIG.

In FIG. 14, the soundproof wall 20 has two ends 22 and three openings 23 and is arranged on the road. Here, the energy flowing from the upper side 21 of the soundproof wall 20 is E1. , i, the energy of the end 22 is E2, i, E
3, i and the energy of the opening 23 is E4, i, E5, i, E6, i.

In FIG. 15, in this embodiment, as in the first embodiment, it is assumed that the information necessary for performing the prediction calculation has already been input. Next, the total energy Eall, i is obtained by the equation (6) (step 201), and the soundproof wall upper side energy E1, i is further calculated (steps 202, 203). Incidentally, the E1, i, is represented by the sound pressure level of the A-weighted, Motomari formula (2), EALL, i is the LWA-8-20log ₁₀ ri in formula (2).

Next, the energy blocked by the soundproof wall is calculated (step 204). Where E0, i ＝
Eall, i-E1, i. This energy E0, i includes the energy at the soundproof wall end 22 and the opening 23 (steps 205, 206), and the energy E2, i, E3, i at the soundproof wall end 22 and the opening Energy E4 at 23,
i to E6, i are calculated (steps 207 to 211).

Since the calculation of these energies can be performed by the calculation method using the path difference described in steps 109 and 110 of FIG. 1, detailed description thereof will be omitted here.

Then, the energies E2, i and E3, i obtained in steps 207 and 208 are combined to obtain the soundproof wall end face energy (step 212). Similarly, step 20
The energies E4, i to E6, i obtained in steps 9 to 211 are combined to obtain the opening energy (step 213).

Next, the total sum of the respective energies thus obtained is obtained, and it is time-integrated within t1 to t2 and converted into a logarithm (steps 214 to 216) to obtain a noise prediction value (single noise exposure level). (Step 217).

As described above, in this embodiment, the soundproof wall upper side energy, the soundproof wall end surface energy obtained by combining the energy of a plurality of ends and the opening energy obtained by combining the energy of a plurality of openings are obtained, and the energy sum is further calculated. Is calculated, time-integrated and logarithmically converted to obtain the total noise level, so that the noise prediction value can be brought close to the actual value, and the change near the boundary can be made closer to the actual value to improve the prediction accuracy. be able to.

A computer program for realizing the noise predicting method of the soundproof wall according to the above-described first and second embodiments is implemented by a magnetic disk such as a floppy (registered trademark) disk, a semiconductor such as ROM, EPROM, EEPROM, and flash ROM. Memory (including those built in cartridges, PC cards, etc.), CD-ROM, D
A program is stored in a portable recording medium such as an optical disc such as VD or a magneto-optical disc such as MO, and the program recorded in the recording medium is a personal computer.
It is also possible to equip the personal computer with the above-described calculation function by installing it in a fixed recording medium such as a ROM, a RAM, or a hard disk built in the computer.

Also, this program is used for LAN, WA
Alternatively, the program may be transmitted via a network such as N or the Internet, and the transmitted program may be installed in a fixed recording medium of a personal computer. Further, this program is not necessarily limited to a single configuration, and may be distributed and configured as a plurality of modules or libraries, and achieves its calculation function in cooperation with an individual program such as OS. It may be one.

The present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention.

[0069]

As described above, according to the present invention, the noise level when there is no soundproof wall and the noise level that wraps around from the upper side of the soundproof wall when there is a soundproof wall are calculated, and the calculated noise level is calculated from the calculated noise level. Calculate the noise level that can be dammed by the noise barrier, and calculate the noise level of the noise barrier end face and the opening from this calculated noise level, and correct it by the diffraction effect. Since the total noise level is predicted by adding the noise level on the upper side, it is possible to improve the prediction accuracy by making the noise prediction value close to the actual value, and especially making the change near the boundary close to the actual value.

Further, according to the program of the present invention, the operation of the noise prediction method according to the invention described in claim 1 can be executed by a computer.

[Brief description of drawings]

FIG. 1 is a flowchart of a calculation procedure for explaining a first embodiment of a noise prediction method for a soundproof wall according to the present invention.

FIG. 2 is a diagram showing a unit pattern obtained by the noise prediction method of the present invention.

FIG. 3 is a diagram showing an example of a plan view showing a sound source, a sound receiving point, and a soundproof wall.

FIG. 4 is an example of a front view of a soundproof wall.

FIG. 5 is a plan view of an end surface of the soundproof wall.

FIG. 6 is a plan view of an opening.

FIG. 7 is likewise a plan view of an opening.

FIG. 8 is likewise a plan view of an opening.

FIG. 9 is likewise a plan view of an opening.

FIG. 10 is likewise a plan view of the opening.

FIG. 11 is a front view showing the configuration of an experiment for verifying the accuracy of the noise prediction method for the soundproof wall according to the present invention.

FIG. 12 is likewise a top view.

FIG. 13 is a diagram showing a unit pattern obtained by the present invention and a conventional method under the same conditions.

FIG. 14 is a diagram showing a configuration of a soundproof wall having a plurality of openings.

15 is a flowchart of a calculation procedure in a second embodiment of the noise prediction method of the present invention used for calculating noise from the noise barrier having the configuration of FIG.

FIG. 16 is a diagram in which a curved road is divided into several sections.

FIG. 17 is a diagram showing a unit pattern showing a time integrated value Ei of squared sound pressure and a total amount E thereof.

FIG. 18 is a diagram showing a unit pattern obtained by a conventional noise prediction method.

[Explanation of symbols]

10 sound sources 11,17 ~ 19 Sound receiving point 12-15,20 Soundproof wall 16 openings 21 Upper 22 Sound barrier end 23 opening

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Mitsugu Ishii             5281 Okazaki, Isehara City, Kanagawa Prefecture (72) Inventor Akira Yabuki             2-6-1, Marunouchi, Chiyoda-ku, Tokyo             Kawa Electric Industry Co., Ltd. (72) Inventor Hakuman Omori             5-1-2 Higashihachiman, Hiratsuka City, Kanagawa Prefecture             Within Kawa Altec Co., Ltd. F-term (reference) 2D001 AA01 DA00                 2G064 AA14 AB04 AB15 BD02 CC29                       CC33 CC46

Claims (2)

[Claims] 1. A noise predicting method using a soundproof wall for soundproofing noise generated from a certain noise source on a road, comprising: a first calculating step of calculating a noise level in the absence of the soundproof wall; In the case, a second calculation step of calculating a noise level that wraps around from the upper side of the noise barrier, and a third calculation of a noise level dammed by the noise barrier
And a fourth calculation step of calculating the noise level of the soundproof wall end face from the noise level calculated in the third calculation step, and a noise level of the soundproof wall from the noise level calculated in the third calculation step. A fifth calculation step of calculating a noise level of the opening, a combined energy of the noise levels calculated in the second, fourth and fifth calculation steps, and a total noise level from the calculated combined energy A noise prediction method using a noise barrier, comprising: a prediction step of predicting. 2. A program for causing a computer to execute the noise prediction method using a soundproof wall according to claim 1.