Laboratory Studies of Ultra-High Sound Insulation of Enclosures

In modern construction practice, enclosing structures with high and ultra-high sound insulating characteristics have come to be actively used. Such structures have rational design solutions according to the sound insulation criterion and are capable of providing the required noise protection of the existing interior spaces. These structures are classified into classes according to sound insulation criteria “A”, “A+”, “A++”. Evaluation of the proper sound insulation of such enclosures in reverberation chambers is complicated by the approach of the sound insulation of such enclosures to the limit values for the test bench used. To improve the accuracy of such studies, it is proposed to use the intensity measurement method. The article presents the results of experimental studies of structures with ultra-high sound insulation in the complex “Large Acoustic Chambers of NNGASU” using the standard technique and the intensity measurement method. In the experiments, indirect sound transmission through the stand structures was simulated by creating artificial sound paths between the reverberation chambers and generating interference noise directly in the low-level chamber. The convergence of the results of determining sound insulation by the two methods under consideration in the absence of interference noise is presented. It is shown that the intensity method allows obtaining reliable results of measuring sound insulation in the presence of flanking noise in the low-level chamber. The flanking noise levels at which ultra-high sound insulation of class “A++” structures can be obtained experimentally using the method of intensimetrу have been determined.