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内墙的隔声改善量ΔR是受内、外墙间空腔和内墙的传声损失、以及墙间基础的传递损失所决定.从厚的外墙到比它薄的内墙传声中,不仅是降低了固体声速度级的绝对值,且内墙上的速度级分布,也在一定程度上反映出外墙上的速度级分布.因此,测量内、外墙上速度(或加速度)级差,可得到ΔR的近似值. 分离的双层墙,在最低简正频率以下,相当于质量阻抗时,内墙的ΔR-f曲线才以40dB/decade递增.实用的大面积内墙,其简正频率很快达到足够的密度,其弯曲波阻抗与频率无关,ΔR-f曲线以20dB/decade而递增. 墙间空腔填吸声材料或墙内加阻尼材料都可提高隔声量.双层墙共用基础或分离基础但无隔振器,则内墙的ΔR分别不大于9或18dB.要使内墙有较高的ΔR,应选用适当f_0的隔振器.压缩量随时间而变的隔振材料不宜用做为隔振器.
Interior wall noise improvement ΔR is affected by the inner and outer walls of the cavity and the inner wall of the sound transmission losses, as well as the transmission of the basis of the loss of the wall of the decision.From the thick outer walls to the sound than thin walls , Not only reduces the absolute value of the solid sound velocity level, but also the speed level distribution on the inner wall, to a certain extent, reflects the velocity level distribution on the outer wall.Therefore, the measurement of the speed (or acceleration) , An approximation of ΔR is obtained. The separation of the double-walled walls, at the lowest normal frequency, corresponds to a mass resistance, the ΔR-f curve of the inner wall increases by 40 dB / decade. The frequency reaches a sufficient density quickly, and its bending wave impedance is independent of frequency, and the ΔR-f curve increases at 20 dB / decade. Acoustic noise can be increased by filling the cavities with sound-absorbing materials in the walls or damping materials in the walls. Common basis or separation foundation but no vibration isolator, then the internal wall of the ΔR were not greater than 9 or 18dB. To make the wall has a higher ΔR, should be appropriate f_0 isolator. Vibration material should not be used as a vibration isolator.