Analysis of creep under compression on impact noise insulation of cementitious plates with EVA waste

Abstract Impact noise in multi-floor buildings is reduced with the execution of a floating floor, which has a resilient material between the subfloor and the slab. In this study, the evaluation of the influence of compression of this material on the acoustic performance of the system was sought. Two resilient materials were compared, one being produced in the laboratory (cementitious plates with EVA - PEVA1,8 waste), and the other commercially (blanket recycled from PET waste - MantaPET). The measurements aiming to relate the dynamic stiffness of the materials and the acoustic performance were up to three years. Additionally, estimates were made for ten years, based on theoretical models and creep compression tests. While PEVA1,8 decreased its dynamic stiffness (20.0 MN/m³ to 17.7 MN/m³) over time, MantaPET increased (2.0 MN/m³ to 3.5 MN/m³), but both maintained intermediate performance (according to NBR 15575-3:2013) to impact noise, presenting L’ nT,w equal to 60 dB and 56 dB in a test floor, respectively. Estimates for ten years indicated less deformation for PEVA1,8 (3.42%), compared to MantaPET (20.15%) and confirmed the trend of changes in the dynamic stiffness, without compromising the acoustic performance of these materials.

摘要：多层建筑中的撞击噪声可通过浮筑楼板系统进行衰减，该系统在结构楼板与面层楼板之间布设弹性支承材料。本研究旨在探究该弹性材料的压缩变形对浮筑楼板声学性能的影响。本次研究对比了两种弹性材料：一种为实验室自制的掺有EVA（Ethylene Vinyl Acetate）-PEVA1,8废料的胶凝板材，另一种为商业化的由PET（Polyethylene Terephthalate）废料回收制成的毯状材料MantaPET。为探究材料动态刚度与声学性能之间的关联所开展的测试周期长达三年；此外，研究人员基于理论模型与蠕变压缩试验，对该系统10年使用周期的声学性能进行了预估。结果显示，PEVA1,8的动态刚度随时间从20.0 MN/m³降至17.7 MN/m³，而MantaPET的动态刚度则从2.0 MN/m³升至3.5 MN/m³；但二者的撞击噪声声学性能均维持在NBR 15575-3:2013标准规定的中等水平，在测试楼板中的归一化撞击声压级L’nT,w分别为60 dB与56 dB。10年使用周期的性能预估结果表明，PEVA1,8的变形量（3.42%）低于MantaPET（20.15%），同时验证了二者动态刚度的变化趋势，且未对这两种材料的声学性能造成负面影响。