초록
본 연구의 목적은 마감모르타르의 물결합재비가 공동주택 바닥충격음에 미치는 영향을 조사하는 것이다. 이를 위하여 동일한 동탄성계수를 지닌 Expanded Polystyrene(EPS) 완충재와 52 %, 66 %, 72 % 의 물결합재비를 가진 모르타르를 활용하여 뜬바닥구조를 시공하였으며, 표준실험동에서 바닥충격음을 측정하였다. 실험결과, 경량충격음에 있어서는 물결합재비 52 % 일 때, 밀도가 높은 관계로 경량충격음 전달특성이 높게 나타났다. 마감모르타르의 물결합재비가 높아지면 완충재 상부층 질량이 낮아지고, 이로 인해 뜬바닥구조의 고유진동수가 63 Hz 대역으로 이동하게 되면서 중량충격음의 음압레벨이 높게 나타났다. 이를 통하여 마감모르타르의 물결합재비가 중량충격음에 미치는 특성을 규명하였다.
The present study aims to investigate the influence of the water to binder ratio of finishing mortar on the floor impact sound of apartments. For this, same resilient materials Expanded Polystyrene (EPS) with constant dynamic stiffness and different mortar layers with 52 %, 66 % and 72 % water to binder ratio respectively were used to build floating floor structures on which floor impact sounds were measured in standard testing facilities. As a result, it was found that light-weight floor impact sound was transmitted well when the water to binder ratio was 52% due to the high density. In case of heavy-weight floor impact sounds, since water to binder ratio of finishing mortar becomes higher as the weight of upper layer of resilient material lighter, it was shown that the natural frequency of floating floor structure moves to 63 Hz bandwidth which eventually cause a higher sound pressure level of floor impact sound. Thus, effect of water to binder ratio of mortar on the heavy-weight floor impact sounds was investigated.