多孔性水泥-聚苯颗粒材料的吸声性能研究

水泥-聚苯颗粒材料被广泛用作外墙外保温材料,通过特殊制备工艺可形成多孔性结构,从而同时具备吸声功能,改善建筑环境.以水泥为胶凝材料,以聚苯颗粒为骨料,以聚丙烯纤维和可再分散乳胶粉为增韧材料,采用半干料压缩工艺成型制备吸声材料,分析了水泥用量和蒸汽养护对材料吸声性能的影响.结果表明:水泥掺量越高,在高频段的吸声系数越低,但水泥掺量过低对低频声的吸收不利;蒸汽养护使材料表面形成了空腔共振吸声结构,对提高一定频率下的吸声性有利,根据理论计算了空腔共振吸声结构提高吸声性的频率范围,结果与实测结果一致,分析认为通过调整聚苯颗粒粒径可实现在相对较宽频率范围的高效吸声;纤维提高了抗折强度,可在保障强度的前提下降低水泥用量以提高吸声性.

Research on the acoustic performance of porous materials with polystyrene and cement

Cement polystyrene particle materials are widely used for exterior insulation materials, which can form porous structure through special preparation and exhibits sound absorbability at the same time. So it can improve the building environment. The sound absorption material is made by compression under certain compression ratio at semi-dry state, using cement as cementing materials, polystyrene grain as aggregate, polypropylene fiber and EVA latex as flexural reinforced materials. The effect of amount of cement and steam curing on the sound absorption coefficient of this material is analyzed. The testing results show that the more the amount of cement, the lower the sound absorption coefficient at high frequency. Too lower amount of cement decreases the sound absorption coefficient at low frequency. With the help of steam curing, resonant cavity structure forms and the sound absorption coefficients at some frequencies increase. Base on theory, the frequency range raised by cavity structure is calculated, and the results are similar to that from actual testing. This paper suggests that the sound absorption coefficient at more frequencies can be advance by adjusting the diameter of polystyrene grain. The polypropylene fiber can enhance the flexural strength. Therefore it is favorable for sound absorbability by using fibers and lower cement.