In railway construction, we are trying to study the pressure wave that is generated in the tunnel entry at the time of high-speed train is emitted in the form of impact noise in the tunnel exit, the tunnel hood installation validity of the tunnel micro-pressure wave reduction measures.
In Korea, Are being investigated tunnel micro-pressure waves at the time of designing the railway, but because there is no acceptance criteria for tunnel micro-pressure wave in the country, it's reality testing realistic isn't carried out
In the case of the Japanese Shinkansen similar most rail and South Korea, Taiwan, Germany, and France, the tunnel is a micro-pressure wave reduction measures in order to keep in determining the acceptance criteria of the tunnel micro-pressure waves, to meet the licensing standards it was prevention in advance complaints micro-pressure wave of possibility to set up, occur in the operation at the time of the train in the future.
Result of the frequency analysis of the tunnel micro-pressure wave, it does not resolve to sound barrier because wavelength and amplitude and possess a sound barrier side of the line is very long in the low-frequency components down to around 100Hz ~ 10Hz.
The high-speed of the train is increased from the time of designing the railway in the future and accurate to the micro-pressure wave damage of micro-pressure wave so as to minimize the residents that live in the vicinity of the tunnel will need to consider to.
Be deemed to be determined to reflect the reduction measures, such as installing a tunnel hood by providing a tolerance of micro-pressure waves within the early in Korea is desirable to do so.