| Keywords |
RT(Reverberation Time) ; RASTI(RApid Speech Transmission Index) ; D50(Definition) ; Multipurpose stadium ; PTFE(Poly Tetra Fluoro Ethylene) |
| Abstract |
Recently sports stadiums have been built not only for athletic sports but also for various events such as live concerts and recitals. The number of the stadiums which are covered by a half dome have been increasing. Therefore it is very important to solve the sound obstacle problem caused by the half dome. But sound designs of most of stadiums, with only a few as an exception, have not been planned properly and the proper sound absorption materials have not been used. This study investigates four World Cup stadiums (Seoul, Incheon, Daegu, Busan). First, sound factors according to the location in the stadium were compared by the design standard through field measurement. Then architectural sound absorption structure was analyzed and in turn the sound factors were considered totally for obtaining the proper reverberation time, RASTI, and sound pressure level. The average reverberation time for dome stadiums Busan were 6.03 seconds, longer than arch(Daegu) stadiums which were 3.8 seconds. However, the variance of the reverberation time at low frequencies(125 Hz and 250 Hz) between the lower tiers(tier 1, 2) and the higher tiers(tier 4, 5) was larger in arch stadiums Daegu by about 2 seconds. The RASTI values for shield kite stadiums Seoul and dome stadiums Busan were between 0.38 and 0.50 indicating that audibility was ‘Poor’ to ‘Fair’. But otherwise, cone stadiums incheon achieved a RASTI value of 0.50 for all spectator seats and arch stadiums Daegu satisfy audibility standards for all areas except the playing field. |