JP2994585B2 - Construction method of shock wave damping work for high-speed vehicle tunnel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock-absorbing workpiece for a high-speed vehicle tunnel for preventing a shock wave generated at an exit side by a shock wave generated in a high-speed vehicle tunnel into which a vehicle enters at a high speed . a method of construction.

[0002]

2. Description of the Related Art Normally, when a high-speed vehicle such as a railway vehicle enters a tunnel at a high speed, an air compression layer generated on the front of the vehicle generates a shock wave sound as a compressed micro-pressure wave at the exit opposite the tunnel. The magnitude of this shock wave sound is proportional to the pressure and pressure gradient of the compressed micro-pressure wave generated when the vehicle enters the tunnel, so that the higher the speed of the high-speed vehicle, the higher the pressure, and the larger the shock wave sound, Noise pollution. In order to suppress the above-mentioned shock wave noise, it is necessary to reduce the pressure of the compressed micro-pressure wave generated when the vehicle enters the tunnel and to make the pressure gradient gentle for soundproofing.

Conventionally, the following means have been tried as the above soundproofing technology. (1) A water spray / shower zone is provided to break down the micro-pressure wave or shock wave propagating in the tunnel. (2) Micro pressure wave or shock wave generated by the approaching vehicle is grasped in advance with a pressure gauge or microphone,
The opposite phase wave is generated and propagated in the opposite direction to cancel the incoming wave in the tunnel. (3) Paste the sound absorbing material on the inner wall of the tunnel. (4) The front surface of the leading vehicle is formed in a spire shape so that rapid compression of air does not occur.

[0004]

SUMMARY OF THE INVENTION The conventional means is
Except for (4), the purpose is to eliminate or reduce the pressure wave having a steep pressure gradient that has already been generated. That is, the means of (1) aims at converting the energy of the compression wave to the kinetic energy of the water droplet to make the pressure gradient gentle, and to reduce the compression wave expansion pressure at the outlet. Means (2) is to eliminate the propagating compression wave by causing interference with the anti-phase wave.However, the capacity of the anti-phase wave generator is huge, that is, the energy of the vehicle entering the tunnel is reduced. It is necessary to have a considerable power, which is not realistic. Means (3) are the most feasible, but the negative wind pressure generated behind a passing vehicle inside a tunnel in a semi-enclosed space is extremely high, and a serious accident may occur due to the peeling off of the attached material. Could lead to Means (4) cannot be expected if the speed of the vehicle increases. SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art and, when a high-speed vehicle enters a tunnel at a high speed, reduces shock wave sound intensity at an exit side due to a shock wave generated in the tunnel . it is an object to provide a method of construction.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies and found that a harmful phenomenon caused by a compressed micro-pressure wave formed when a railway vehicle enters a tunnel at a high speed. The inventors have found that it is effective to moderate the pressure and pressure gradient of the compressed micro-pressure wave front to such an extent that it does not occur, and have completed the present invention.

[0006]

[0007]

According to the present invention based on the above-mentioned knowledge, when constructing a shock wave damping shroud on the entrance wall of a tunnel pit for a high-speed vehicle, the height of the shroud from the roadbed surface is increased as approaching the inside of the tunnel. 1/4 of the traveling distance (m) per second of the vehicle entering from the position where there is no surrounding wall to the position where the surrounding wall is constructed around the entire entrance of the tunnel tunnel
With building a surrounding wall so that the above length, DOO
Prescribe the area where the surrounding wall is built around the tunnel entrance
In the position, 1/50 of the tunnel radius is the lower limit, and 1/10
With a width within the range of the upper limit
A gist of the present invention is a method for constructing a shock wave shock-absorbing workpiece for a high-speed vehicle tunnel , wherein an opening is provided in at least one step .

[0009]

[0010]

The present invention can of course be applied to a newly created tunnel. However, even in an existing tunnel, by applying the present invention, it is possible to reduce the generation of a shock wave sound at the tunnel exit due to a shock wave which has been a problem in the past. It is possible to eliminate. That is, the surrounding wall formed so that the rate of covering the entering vehicle in the cross-sectional direction gradually increases from the roadbed surface toward the inside of the tunnel is attached to the tunnel pit entrance wall surface for the high-speed vehicle, and the entire circumference of the surrounding wall is Across
By providing at least one stepped opening in the shape of a round slice, the pressure rise gradient of the compressed micro-pressure wave at the time of entry into the vehicle can be moderated, and the formation of the compressed micro-pressure wave can be prevented, or The intended purpose is achieved here, since the pressure gradient just before the compression wave can be prevented from rising to the extent that no harmful phenomena occur.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, will be explained with reference to attached <br/> Te accompanying drawings embodiments of the present invention. Usually, a tunnel for a high-speed vehicle, for example, a tunnel for a railway vehicle, is constructed so that there is a substantially constant interval between the tunnel and the vehicle. The cross-sectional area of the vehicle occupying the tunnel cross-sectional area is quite large, and when a railway vehicle enters the tunnel mine at high speed, a compression wave in which air is compressed is formed in the traveling direction of the vehicle, and the vehicle moves forward faster than the vehicle travels. When it moves and this compression wave leaves the tunnel exit, it generates a so-called shock wave sound. Therefore, in the present invention, the formation of the compressed micro-pressure wave generated on the front surface of the vehicle entering the tunnel is positively prevented or reduced, and for that purpose, an enclosing wall formed by cutting the cylindrical body obliquely is used. I'm using

FIG. 1A is a plan view of a shock wave buffering enclosure (hereinafter, abbreviated to an enclosure) 1 according to an embodiment of the present invention, and FIG. 1B is a side view and FIG. (c) is also a perspective view. The enclosure wall 1 shown in FIG. 1 is for reducing the compressed micro-pressure wave generated by the above-mentioned high-speed entry of the vehicle, and as shown in FIGS. 1 (a) to 1 (c), the entrance wall of the tunnel 2 The wall is constructed so as to extend from the tunnel 2 so as to extend from the entrance side so as to cover the wall of the tunnel 2 with a certain length.

The enclosure wall 1 provided in this manner is just
The cylindrical body is cut obliquely, and the length L of the inclined portion is one of the traveling distance (m) per second of the high-speed vehicle that enters, regardless of the height of the tunnel 2.
The effect starts to appear from a length of about / 4 or more, and the longer the length, the greater the effect of smoothing the pressure gradient of the compressed micro-pressure wave front.

In this case, the pressure of the compressed micro-pressure wave is increased by gradually increasing the ratio of the surrounding wall 1 to the entire space around the vehicle 5 (vehicle cross-sectional covering ratio) toward the entrance of the tunnel 2. The slope becomes gentle. Furthermore, the surrounding wall 1 is provided with a circular section-shaped opening 3 having a predetermined width in the axial direction in a cylindrical portion formed so as to cover all of the approaching vehicle 5 in the cross-sectional direction near the entrance of the tunnel 2. Is provided. By providing the opening 3 in this way, the pressure in the pressurized space formed by being compressed from the entrance side of the enclosure wall 1 to the opening 3 is released and reduced, and the pressure gradient is further reduced. .

By the way, in the conventional tunnel without the surrounding wall 1 shown in FIG. 1, the shock wave sound level at a point 20 m (45 ° direction) from the center of the tunnel exit is 110 dB as shown in FIG. 2 (a). , Which is annoying as a very loud shock wave sound, but has an inclined wall L = 30 m
In the case of the present embodiment, as shown in FIG. 2B, the level of the shock wave sound at a point 20 m (45 ° direction) from the center of the tunnel exit is 64 dB, which is almost the same as the noise during normal vehicle running. There was no one. Incidentally, [Delta] P / P _O in the figure represents the pressure ratio, the [Delta] P is the P _i -P _O. Here, P _{O is} the atmospheric pressure, and P _{i is} the air pressure after 1 ms (millisecond) at the entrance.

As described above, the opening 3 is formed in the cylindrical portion formed so that the surrounding wall 1 covers the entire cross section of the vehicle 5.
In the case of the structure including the pressure, the pressure gradient immediately before the pressure becomes maximum is smaller than the pressure gradient at the tunnel entrance as compared with the broken line without the opening 3 as shown by the solid line in FIG. rising gradient becomes gradual, the following formula _{(P 30 -P 20) <(} P'30 -P' 20) However, in the case of there cutting openings a, P _20: inlet at 20ms of (milliseconds) during elapsed for no inlet at a 30 ms (milliseconds) has elapsed when the pressure cut opening a, _P'20:: pressure P ₃₀ 20 ms at the inlet (milliseconds) pressure during the elapsed _P'30: inlet in the 30 ms (milliseconds ) As the pressure elapses, the shock wave noise at the tunnel exit becomes smaller in proportion to this gradient. The width W of the opening 3 is suitably in a range from 1/50 to 1/10 of the tunnel radius. For example, the tunnel radius is 5000mm
In the case of (1), at W <100 mm, the peak height of P ₃₀ hardly changes, and when 500 ≧ W> 200 mm, P ₃₀ decreases in proportion to W. Further, when W> 500 mm, even if W is increased, P _{30 is} constant, and a large effect is not observed.

In the embodiment of the present invention shown in FIGS. 1C and 4, a gas permeable sound absorbing material 4 is adhered to the inner surface of the enclosure wall 1 with an air layer D behind. ing. By adhering the breathable sound absorbing material 4 in this manner, the pressure and pressure gradient of the compressed micro-pressure wave formed on the inner surface of the surrounding wall 1 are further reduced. The result is shown by a solid line in FIG. 5, but when compared with that shown by a broken line having no sound absorbing material, the pressure at the time of forming the compressed micro-pressure wave is reduced due to the ventilation resistance of the sound absorbing material, and the pressure rise rate is reduced. The rising slope of the wave becomes gentle. In this case, the air layer D behind the sound absorbing material is 30 m
The effect becomes more remarkable at a thickness of m or more.

The surrounding wall 1 according to the embodiment of the present invention can be made of a normal tunnel building material. In particular, by using a porous building material having a small specific gravity, a compressed micro-pressure wave can be obtained. Pressure and pressure gradient can be effectively alleviated, and the shock wave noise at the outlet can be reduced.

[0019]

Since the present invention is constructed as described above, the surrounding wall and the at least one-stage opening in a ring-shape are provided.
Only adding a simple construction of providing the bets, when the vehicle enters the tunnel at high speed, by the shock wave generated in the tunnel, excellent effect response rates that can be prevented shock wave sound that occurs at the outlet side It is extremely useful industrially.

[Brief description of the drawings]

FIG. 1 is a plan view of an enclosure wall 1 according to an embodiment of the present invention.
(a), side view (c) and perspective view (c).

Fig. 2 In the case of a tunnel without a shock wave enclosure (a)
7 is a comparison graph of sound pressure levels between the case of the tunnel having the surrounding wall 1 according to the embodiment of the present invention and the case (b).

FIG. 3 is a comparison graph showing a change in pressure gradient of a compressed micro-pressure wave in the case of an enclosure wall 1 provided with an opening 3 according to an embodiment of the present invention.

4 is a cross-sectional view of the enclosure wall 1 according to another embodiment of the present invention.

5 is a comparative graph showing compression pressure gradient change in the micro-pressure waves circumference Ikabe 1 that will be shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Enclosure wall 2 ... Tunnel pit 3 ... Opening 4 ... Breathable sound absorbing material 5 ... Vehicle

Continuation of the front page (56) References JP-A-7-229390 (JP, A) JP-A-5-108079 (JP, A) JP-A-5-321592 (JP, A) JP-A-5-113093 (JP) , A) Hikaru 4-138499 (JP, U) Jiko 52-12364 (JP, Y2) (58) Fields studied (Int. Cl. ⁶ , DB name) E21D 9/14

Claims (1)

(57) [Claims] 1. Impact on the entrance wall of a highway vehicle tunnel
When constructing wave-enclosing enclosures,
As you approach, increase the height of the surrounding wall from the roadbed surface
From the position where there is no surrounding wall
Per second of the vehicle entering the position where the vehicle is built
Configure the surrounding wall to be at least 1/4 of the distance (m).
And an enclosing wall was built around the entire entrance of the tunnel.
1/50 of the radius of the tunnel
The lower limit and the entire circumference with a width within the range of 1/10 as the upper limit
At least one opening should be provided in a round section over
For shock wave buffering of tunnels for high-speed vehicles, characterized by
Construction method of the object.