Analysis of partial venting in continuous and point isolated concrete floating floors

Concrete floating floors are frequently used to improve airborne and impact sound insulation in buildings. If trapped air between the structural slab and topping slab is not adequately vented, the natural frequency of the spring-mass system is significantly increased due to air stiffness. Unger (1975) showed how stiffness, transmissibility and limiting radii could all be theoretically established in vented and unvented floors. In this paper, we measure laboratory and field installations with variable venting conditions and compare empirical data to the previously established theory. The vented area is changed, and natural frequency response is measured in an effort to establish some trends in partially vented floors. These effects are observed for continuous elastic layer floors and compared to discrete isolation systems.