KR100449509B1 - Draft hole type train tunnel - Google Patents

Abstract

The present invention relates to a 0.75km-class ventilated open tunnel for reducing wind pressure fluctuations and reducing air pressure waves.

In the present invention, the ventilation holes are formed on both sidewalls of the small cross-section tunnel, and the volume design value for the spacing, quantity, and inner diameter of the ventilation holes is derived through the scale model test, and the wind pressure fluctuation reduction and tunnel micro-pressure of the existing railway as well as the high-speed railway are obtained. It can be used as a wave reduction measure, and 0.75km grade ventilated tunnel is provided for reducing wind pressure fluctuations and reducing air pressure waves, which can reduce passenger's tinnitus and reduce the tunnel area and improve train speed.

Description

0.75km-class ventilated single tunnel for reducing wind pressure fluctuations and reducing micro-pressure waves {DRAFT HOLE TYPE TRAIN TUNNEL}

The present invention relates to a 0.75km-class ventilated single tunnel for reducing wind pressure fluctuations and reducing micro-pressure waves. More specifically, the vent holes are formed on both sidewalls of a small cross-section tunnel, and the gaps and the number of vents are measured through a scale model test. By deriving the volumetric design value for the inner diameter, it can be used to reduce pressure fluctuations and micro-pressure waves in existing high-speed railway tunnels as well as existing railways. The present invention relates to a 0.75km-class ventilated tunnel for reducing wind pressure fluctuations and reducing micro-pressure waves.

In general, tunnels carried by railways generate pressure waves when a high-speed train enters the interior of the tunnel, i.e. in front of the front of the train head near the entrance of the tunnel.

This pressure wave compresses and accelerates the air which is stopped in front of the wave and propagates along the tunnel at the speed of sound, which is reflected back toward the train as an expansion wave at the exit of the tunnel and at the same time the pulsed pressure wave is reflected from the exit environment. It is radiated outward.

The above phenomenon occurs in three steps as shown in FIG.

In the first stage, pressure waves are formed as the high-speed train enters the tunnel, and in the second stage, the pressure waves propagate into the tunnel and the pressure waveform is deformed. In the third stage, micro pressure waves are generated from the tunnel exit. It is radiated.

These shock waves generate powerful noises like the sonic boom generated by supersonic airplanes. These low-frequency vibrations vibrate the windows and door frames of neighboring private houses, requiring countermeasures. 110 km / h h Abnormal tunneling causes problems such as ringing due to fluctuations in air pressure and tinnitus.

Therefore, the approach to reduce the strength of the pressure fluctuations presented so far is to increase the cross-sectional area of the tunnel, the method of varying the tunnel cross-sectional area in the shape of a trumpet at both ends of the entrance and exit of the tunnel. There is a way to install multiple vents in the tunnel,

In the above method of increasing the cross-sectional area, it is known that the peak pressure change decreases by 49% when the tunnel cross-sectional area is increased to 100%. However, this is not only a problem that excessive construction cost is expended. Is not effective because it is only 26% greater than the reduction obtained when 20 ventilation holes with a diameter of 2.7m are installed in the tunnel at 20m intervals.

As shown in FIG. 2, the method of varying the tunnel cross-sectional area in a trumpet shape is to make the trumpet shape 1/3 of the tunnel length in order to effectively reduce the pressure fluctuation, and to have an entrance area of 2.5 times the basic cross-sectional area of the tunnel. For double track tunnels, the trumpet-shaped tunnel cross-sectional change is applied to both ends of the tunnel. For tunnels of 1140 m, the tunnel cross-sectional area decreases linearly up to a distance of 82 m ² for a 380 m length. The tunnel is known to reduce the peak pressure change in the tunnel by 60%, but the trumpet-shaped tunnel has a complicated structure, which requires a lot of equipment cost.

On the other hand, in the method of installing a plurality of ventilation holes in the tunnel as shown in Figure 3 by installing three pairs of ventilation holes in the tunnel inlet / outlet area, and installing a 0.72m diameter ventilation wall at 25m intervals in the middle of the double track track tunnel It is known to reduce construction cost by 20% of internal hole cross section, which was actually applied to the new tunnel of TGV route (Paris-Amsterdam) in Netherlands in 1998.

In the case of the ventilator of FIG. 4, it is known that Germany has an effect of increasing the operating speed by 20% as an example applied to an ICE route tunnel in Germany, which increases the tunnel traveling speed from 250 km / h to 300 km / h. This effect is the same as the result when the tunnel internal area is expanded by 100%.

Therefore, the approach to reduce the intensity of pressure fluctuations in tunnels is compressed by trains through a number of vents when compared to the method of increasing the area of the tunnel in the tunnels or improving the tightness of the train to improve passenger comfort. It can be seen that the installation method of ventilating hole which gradually discharges the outside air to compress the air in the tunnel when entering the train tunnel is a relatively simple and economical measure.

On the other hand, in Korea, existing railway tunnels of Gyeongbu Line or Honam Line have very small internal cross-sectional area of tunnel (4 types of single-line tunnel: 24 ~ 28 m ² ), which is a major obstacle to the speeding up of existing lines, and most of them were constructed before 1950s. Is a tunnel that makes trains run at low speeds,

Currently, the design of new tunnels following the relocation of the Gyeongchun, Yeongdong, and Jungang Lines, which has a large proportion of tunnels, began in late 1999, but only the aerodynamic review of the designed design was carried out. As a result, the reduction plan of tunnel internal area has not been applied.

Therefore, in the case of speeding up the existing existing ship, the ventilation hole is applied to the old tunnel which has a relatively small cross-sectional area, and it can be replaced by the new ventilation hole tunnel by expanding the cross-sectional area or relocating the railway. As well as securing driving performance, the construction of new tunnels by relocation is urgently needed to secure the optimal tunnel design technology by aerodynamics.

Meanwhile, the ICE route tunnel shown in FIG. 4 is a double-track tunnel, and the toffee is about 50m, and the working conditions are more disadvantageous than in the case of domestic conventional tunnels. In Korea, the toffee average is about 50% higher than that of Germany. to be.

In addition, the installation of 50 ventilation holes with a diameter of 1m in a double track tunnel of about 1km in length can reduce the worst pressure fluctuations that occur when trains operate by almost 60%. In case of introduction to the tunnel, the extension length of the tunnel was different and it could not be applied to the 0.75km tunnel which is the disconnection tunnel.

Therefore, the present invention in forming a ventilated tunnel that can reduce the passenger's sense of tinnitus and micro-pressure waves of the tunnel exit as described above, through the scale model test for the 0.75km tunnel, which is a small cross-section tunnel, By deriving the volumetric design values for spacing, number, and inner diameter, it can be used to reduce pressure fluctuations and micro-pressure waves of existing high-speed railway tunnels as well as existing railways, reducing passengers' sense of tinnitus and reducing the tunnel cross-sectional area. The purpose of the present invention is to provide a 0.75km-class ventilated tunnel for reducing wind pressure fluctuations and reducing air pressure waves, which can improve speed.

As a specific means of the present invention for achieving the above object;

In the ventilation type tunnel in which a plurality of ventilation holes are formed in the tunnel in order to reduce wind pressure fluctuations and micro pressure waves, and to reduce the area of the tunnel.

It is realized through the 0.75km-class ventilated tunnel for reducing wind pressure fluctuations and reducing micro-pressure waves, with 38 articulated vertical vents located at mutually symmetrical positions on both sides of the 0.75-km-class tunnel.

1 is a state diagram showing a process of generating a microbarium wave

2 is a configuration diagram of a tunnel in which the tunnel cross-sectional area is changed in a trumpet shape;

3 is a block diagram of a conventional ventilated tunnel

Figure 4 is another embodiment configuration of a conventional ventilated tunnel

5 is an overall configuration diagram of a 0.75km-class ventilation hole tunnel for reducing wind pressure fluctuations and reducing air pressure waves according to the present invention.

FIG. 6 is a diagram illustrating a configuration in which a pressure sensor, a photo sensor, and a microbarometer are positioned to measure wind pressure fluctuations in the tunnel model inner wall and noise pressure impact noise measurement at the tunnel exit;

7 to 10 is a graph showing the test results for each position of the wind pressure sensor for the tunnel entry speed 110km / h class.

11 to 14 is a graph showing the test results for each position of the wind pressure sensor for the tunnel entry speed 150km / h class.

15 to 18 is a graph showing the test results for each position of the wind pressure sensor for the tunnel entry speed 180km / h class.

19-21 is a result table showing the results of the maximum wind pressure fluctuation value of the graph for the train entry speed in the tunnel;

22 is a result table showing a reduction coefficient of the maximum atmospheric pressure wave for each train entry speed.

Figure 23 is a graph showing the reduction rate of the maximum air pressure wave value according to the change in the inner diameter of the pressure reducing duct for 150 ~ 180km / h by train entry speed

24 is a configuration diagram of a train model test apparatus for testing a 0.75km-class ventilation hole disconnection tunnel for reducing wind pressure fluctuations and reducing air pressure waves according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

5 is an overall configuration diagram of a ventilation type tunnel for reducing wind pressure fluctuations and reducing air pressure waves according to the present invention.

As shown in the drawing, the ventilated tunnel of the present invention is located in a symmetrical position on both sides of the inner surface of the 0.75km-class tunnel, which is a small cross-section tunnel. It is characterized by forming an articulated vertical vent hole of the same form.

Here, 1/61 scale filed as a patent application No. 2000-64426 filed by the Korea Railroad Research Institute, which is the applicant of the present invention, to obtain the optimum design value for the gap, quantity, and inner diameter of the vent hole of the 0.75km-class ventilated tunnel of the present invention. The tunnel driving train model tester (shown in Figure) was applied to identify the effect of reducing wind pressure fluctuations in the tunnel.

At this time, numerical analysis of a 4-car one train train was performed for the actual 763.84m tunnel to be tested, and the test data were compared for the tunnel without the ventilation holes. Numerical analysis was carried out with an abnormal one-dimensional analysis as shown in Tables 1 and 2 below for the actual curve size of (Ambient temperature at 293 K and atmospheric pressure at 102,100 Pa).

Item Specification Effective area of train 9.8 m ² Before head shape Saemaul Lake Streamlined Train car 12.08 m Vehicle organization 4-car 1 set (2M + 2T) Vehicle length 94.30 m (4 cars)

Thus, in the 1/61 scale tunnel model test, the length of tunnel model was 12.522m (scale 763.84m), the length of train model was 1,546m (scale 94.3m), and the wind pressure fluctuation measured at the tunnel inner wall and the exit of tunnel exit A pressure sensor, a photo sensor, and a microbarometer are positioned as shown in FIG.

In addition, by changing the number of ventilation holes (10 ~ 38) for the tunnel model, and by changing the left and right arrangement of the ventilation holes, the wind pressure fluctuation reduction performance in the tunnel, the ventilation flow rate of the ventilation holes, the micro-pressure wave reduction performance as shown in Table 3 below The test was performed, and the side wall arrangement of the ventilation holes in the tunnel was arranged to face each other and cross each other as shown in Table 4 below. As shown in Table 4, 37 ventilation holes in the left and right sides of the tunnel side wall were shown. There is a hole for installing the hole and the unused hole is sealed with a stopper.

number Tunnel Model Length Train model formation and speed Ventilation bore size change Ventilation ventilation Ventilation Array Change Vent hole height change Ventilation performance test One 12.522 m 4 fleet110 km ～ 180 km - none - - - 2 12.522 m 5 Cars1 Combination110 km ～ 180 km - none - - - 3 12.522 m 5 Cars1 Combination110 km ～ 180 km Inner diameter35 mm All 38 Symmetrical arrangement Window side: 19 Inside: 19 340 mm 1 ventilation flow rate 4 12.522 m 4 fleet110 km ～ 180 km Inner diameter35 mm All 38 Symmetrical arrangement Window side: 19 Inside: 19 340 mm 1 ventilation flow rate 5 12.522 m 4 fleet110 km ～ 180 km Inner diameter16 mm All 38 Symmetrical arrangement Window side: 19 Inside: 19 340 mm 1 ventilation flow rate 6 12.522 m 4 fleet110 km ～ 180 km Inner diameter35 mm All 19 Cross arrangement window side: 9 inside: 10 340 mm 1 ventilation flow rate 7 12.522 m 4 fleet110 km ～ 180 km Inner diameter35 mm All 15 Cross arrangement window side: 5 inside: 10 340 mm 1 ventilation flow rate 8 12.522 m 5 Cars1 Combination110 km ～ 180 km Inner diameter35 mm All 15 Cross arrangement window side: 5 inside: 10 340 mm 1 ventilation flow rate 9 12.522 m 4 fleet110 km ～ 180 km Inner diameter16 mm All 15 Cross arrangement window side: 5 inside: 10 340 mm 1 ventilation flow rate 10 12.522 m 4 fleet110 km ～ 180 km Inner diameter35 mm 10 things Symmetrical arrangement Window side: 5 Inside: 5 340 mm 1 ventilation flow rate

Tunnel entrance (1) Number of ventilation holes: total 38 (symmetrical arrangement), ventilation hole spacing: 0.67 m (scale 40.87 m) Medial 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 Outside 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 Tunnel entrance (2) Number of vents: 19 in total (crossed arrangement), clearance gap inside: 1.34 m (scale 81.74 m), outside: 1.34 m (scale 81.74 m) Medial 3 7 11 15 19 23 27 31 35 Outside 1 5 9 13 17 21 25 29 33 37 Tunnel entrance (3) Number of vents: 15 in total (crossed arrangement) Vent gaps Inside: 2.68 m (scale 163.48 m), Outside: 1.34 m (scale 81.74 m) Medial 3 11 19 27 35 Outside 1 5 9 13 17 21 25 29 33 37 Tunnel entrance (4) Number of vents: 10 in total (symmetrical arrangement) Vent gaps: 2.68 m (scale 163.48 m) Medial 3 11 19 27 35 Outside 3 11 19 27 35

Thus, for the four-car train model described above, the wind pressure fluctuations were compared according to the number of vents at 35mm in diameter (2.27m in actual size) and 340mm in height (20.7m in height). m) Wind pressure fluctuations in the tunnel model were measured by varying the distance and arrangement of the ventilation holes based on the ventilation holes located at the distance.

7 to 10 are graphs showing the test results for each position of the wind pressure sensor for the tunnel entry speed 110km / h class, Figure 11 to 14 is a graph showing the test results for each position of the wind pressure sensor for the tunnel entry speed 150km / h class 15 to 18 are graphs showing the test results for each position of the wind pressure sensor for the tunnel entry speed of 180 km / h.

As can be seen from these test results, the installation rate of 15 and 19 air vents in the left and right walls in alternating arrangement is almost the same as the reduction rate of the maximum peak of wind pressure fluctuation compared to the installation of 10 air vents in a symmetrical arrangement. In the case of 38 air vents, the reduction rate of the maximum peak of wind pressure fluctuation was improved by about 10%.

19 to 21 show the results of the maximum wind pressure fluctuation peak value of the graph for the train entry speed in the tunnel. As shown in the results, when the train entrance speed is constant, the number of ventilation holes is compared only when the ventilation holes are symmetrically arranged. Increasing by about 4 times, it can be seen that the reduction rate of the maximum wind pressure fluctuation increases by about 10%.

On the other hand, in Figure 22 (results table showing the reduction coefficient of the maximum air pressure wave value for each train entry speed) and Figure 23 (reduction rate of the maximum air pressure wave value according to the number of vertical vent holes for the train entry speed 150 ~ 180 km / h As shown in the graph.), When 10 ventilation holes are applied, the micro-pressure wave reduction rate is about 52.5%, and when the number of ventilation holes is increased by 4 times to 38, the micro-pressure wave reduction rate is increased by about 8%. have.

Therefore, when the ventilation holes are applied to the 0.75km-class single tunnel, the ventilation holes are installed at 38 symmetrical positions in the left and right sides of the ventilation holes, but each of the ventilation holes has a space of 40.8m and a diameter of 2.27m. It can be seen that the most effective in reducing the fluctuations, and in addition, it is possible to reduce the micro-pressure waves as well.

As described above, the 0.75km ventilated tunnel for reducing wind pressure fluctuations and micro-pressure waves according to the present invention derives the optimum design values for the distance, number, and inner diameter of the vent for the 0.75km-class tunnel, which is a small cross-section tunnel, It can reduce wind pressure fluctuations in tunnels of existing railways as well as high-speed railways by 50% or more, and also reduce air pressure waves by 40% or more. In addition, it is possible to reduce the construction area by reducing the tunnel cross-sectional area, and also has the effect of improving the tunnel operating speed of the train.

Claims (3)

In the ventilation type tunnel in which a plurality of ventilation holes are formed in the tunnel in order to reduce the air pressure wave and the area within the tunnel, A ventilated tunnel for reducing wind pressure fluctuations and reducing micro-pressure waves in a 0.75km-class tunnel, wherein 38 articulated vertical vents are formed at mutually symmetrical positions on both sides of a 0.75km-class tunnel. The ventilation tunnel of claim 1, wherein the ventilation holes have a spacing of 40.8 m. According to claim 1, wherein the ventilation hole is a ventilation hole tunnel for reducing the wind pressure fluctuations and micro-pressure wave in the 0.75km class tunnel, characterized in that the diameter of 2.27m.