Avaliação da influência da compressão de placas cimentícias com resíduo de EVA como material resiliente alternativo no isolamento ao ruído de impacto

• Autor(a) principal: Santos, Fabianne Azevedo dos
• Data de Publicação: 2020
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/18593
• topic: Material resiliente; Influência da compressão; EVA; Ruído de Impacto; Rigidez dinâmica; Avaliação; Resilient material; Influence of compression; Impact Noise; Dynamic stiffness; CNPQ::ENGENHARIAS::ENGENHARIA CIVIL

The noise of impacts on the floors of multi-floor buildings has been characterized as something that increasingly compromises the coexistence between neighbors of overlapping autonomous units. The practical measures to face this problem resort to the execution of floating floors, even during the works of the building, in which a resilient material is used between the structural slab and the subfloor. The problem in focus in the present study is centered on changing the dynamic stiffness of the resilient material, during its useful life, and on the possible variation of the acoustic insulation capacity of the floor system. The objective was to evaluate the influence of compression on the proposed resilient material with cements boards agglomerated with EVA waste and the degree of impairment of its acoustic performance in a floating floor system, regarding the isolation of impact noise, based on the observation of its characteristic of dynamic stiffness. The experimental studies evaluated two different resilient materials, comparing alternative and commercial samples, both made using waste: EVA from the shoe industry, transformed into light aggregates and used in the production of cements boards (PEVA1,8); and the blanket composed of fibers recycled from PET waste (MantaPET). The highlight of the analyzes is for the PEVA1,8 boards, produced in the laboratory, through a different molding process, in order to obtain adequate characteristics for an alternative resilient material. The evaluation of these materials was based on a procedure of influence of the compression, up to three years with the resilient material confined between two boards (simulation of the material between slab and subfloor), and on a behavior estimate for up to ten years, seeking to relate the acoustic performance and service life when applied to floating floor systems. The indicators adopted were dynamic stiffness and impact noise isolation, with partial evaluations up to 3 years (every 12 months), one of the samples with PEVA1,8 plates being evaluated without interrupting the compression process in the three years. The acoustic tests with the resilient materials were carried out in a chamber containing a conventional precast slab. The analysis procedures adopted in the tests of impact noise in the floor system, dynamic stiffness and creep to compression of resilient materials were supported by current standards. The variation in the initial acoustic insulation capacity of the PEVA1.8 board was only 1 dB (61 dB / 60 dB) after three years of compression in the set, maintaining the same intermediate performance classification, according to NBR 15575: 2013, while the its dynamic stiffness varied from 20,0 MN / m³ to 17,7 MN / m³ and to 13 MN / m³, when it did not interrupt the compression. That is, over three years, the PEVA1,8 board tends to lose rigidity, but practically unmatched with an increase in sound insulation. MantaPET varied its dynamic stiffness from 2 MN / m³ to 3,5 MN / m³ after two years of compression influence. The notable fact is that while the PEVA1,8 board tends to lose rigidity during use over time, MantaPET tends to increase its rigidity, although such a blanket still remains quite efficient in its sound insulation capacity. In the behavior estimate for ten years, it was possible to verify a smaller deformation for PEVA1.8 (average of 0,73 mm; 3,42%), compared to MantaPET (average of 1,71 mm; 20,15%), as well as similar trends regarding variations in dynamic stiffness were confirmed: reduction to PEVA1,8 and increase to MantaPET. However, such estimates, calculated based on theoretical models, showed that the insulation capacity of both resilient materials studied would not be compromised after ten years of application on floating floors. Therefore, it can be said that PEVA1,8 does not have the same insulation efficiency to impact noise on the floor, compared to MantaPET (56 dB), but the board has the potential to be used as a resilient material in floating floor systems, since in its composition, EVA, in combination with Portland cement, gives an interesting characteristic, which due to the little deformation of the plates over time, can provide greater stability to support the weight of the materials added on them, after the execution of the floating floor.