Concrete panels (floor slabs and walls) have been experimentally studied to determine the airborne sound insulation of those with cylindrical circular hollows, compared to solid concrete panels of the same surface density. Both room-size and small-scale models have been investigated. Probable sound-transmission phenomena (for example, resonances of air in the hollows) have been considered. A dynamic analogy with ribbed panels is also shown to be close. A simple predictive formulation is validated. The results obtained are found to be of practical importance. © 1995.
Vinokur, R. Y. (1995). Sound insulation by concrete panels with cylindrical circular hollows. Applied Acoustics, 45(2), 131–138. https://doi.org/10.1016/0003-682X(94)00041-S