Floor Impact Noise Characteristics of Impact Ball Depending on the Drop Heights in the both Wooden and Concrete Structures
Won-Hak Lee, Chan-Hoon Haan · 2010
This study aimed at measuring impact sound by drop heights using the impact ball adopted as the standard heavyweighting impact source in Japan, comparing them with the jumping impact sounds that are the actual impact sources so as to examine the most similar drop heights to the actual impact sound and review the error that may occur from impact ball. In addition, the study was intended to find out the difference of the materials and method for installation by having the tests under the same condition performed in the laboratory building for timber structure of BRI in Japan and concrete structure of KIMM in Korea. According to the result of study, impact sound was found to show the similar sound pressure level to actual one at the drop height of 10 ~ 30cm in timber structure, while there was no similar height of sound pressure but it was desirable to drop at the height of 100~110cm to maintain a quiet environment in the concrete structure. In addition, the error that may occur from the difference of height of 10m up and down based on the standard drop height caused by the impact ball operated by human hands was approx. 1dB or less only in its value of characteristic, but it must be carefully taken into account in the L-Index assessment.