How to Optimize the Acoustic Performance of Perforated GRC Panels? Sound Absorption Mechanism and Qinglong Group's Integrated Acoustic Decoration Technology

The acoustic performance optimization of perforated GRC panels aims, through a systematic approach of "perforation parameter design, rear cavity construction, sound-absorbing material filling, and overall system integration," to elevate them from mere decorative components into integrated acoustic-decorative products with good sound absorption (especially in the mid-to-high frequency range). Their sound absorption mechanism is mainly based on the Helmholtz resonance principle and the sound absorption principle of porous materials. In a high-end theater in Shenzhen and multiple office conference center projects, Qinglong Group optimized the perforation rate (15%-25%), hole diameter (φ2-φ8mm), and panel thickness (12-20mm), together with the coordinated design of rear cavity depth (100-300mm) and centrifugal glass wool filling, achieving a noise reduction coefficient (NRC) of 0.60-0.85 for the GRC acoustic construction, perfectly balancing architectural aesthetics with indoor acoustic comfort. Acoustic optimization is an innovative fusion of function and form.

Perforation Parameters Are the "Mixing Console" of Acoustic Performance

The perforation rate, hole diameter, and panel thickness jointly determine the resonance frequency of the perforated panel. The higher the perforation rate, the more the absorption peak frequency shifts toward high frequencies; the smaller the hole diameter, the higher the peak sound absorption coefficient, but the narrower the frequency band; as panel thickness increases, the resonance frequency shifts toward low frequencies. Through calculation and testing, the Qinglong acoustic laboratory customizes optimal perforation schemes for different frequency band requirements (such as the 500-4000Hz needed for speech clarity), and uses parametric design to achieve artistic effects with patterned perforations.

The Rear Cavity and Filling Are Performance Amplifiers

The depth of the rear cavity directly affects the sound absorption frequency band. The deeper the cavity, the more the absorption peak shifts toward low frequencies. Filling the cavity with porous sound-absorbing materials (such as glass wool or rock wool) can significantly widen the absorption frequency band and improve the mid-to-high frequency absorption coefficient. We typically use 50mm-thick centrifugal glass wool with a density of 32-48kg/m³, wrapped in non-woven fabric to prevent fiber escape.

System Construction and Installation Details Determine the Final Result

The joints between GRC panels and keels, and between panels, must be sealed to prevent acoustic short-circuiting that would compromise low-frequency absorption. Sound insulation treatment is also required between the cavity and the main structure to avoid structure-borne sound transmission. We provide complete acoustic detail construction drawings to ensure that acoustic performance is realized from design through construction.

Upgrading from Decoration to Acoustic Decoration

Through acoustic optimization, perforated GRC panels are no longer just for show, but active acoustic adjustment elements. They can be used in gymnasiums, subway stations, restaurants, and other venues that need to control reverberant noise, as well as in concert halls, theaters, and other spaces requiring fine acoustic tuning, achieving "invisible acoustic decoration." Qinglong Group can provide professional acoustic calculation reports and component performance test data.

Integrating acoustic functions into GRC decorative panels is an important trend in integrated architectural design. With its cross-disciplinary integration of materials and acoustics technologies, Qinglong Group provides higher-value solutions for space creation.