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Published on: February 17, 2019
A Constrained Layer Damping Perspective on Floating Floor Systems for Low-Frequency Impact Noise Control.
Yinghui Jiao1, Junhuai Xu2,3, Yaohan Feng2
1College of Geography and Planning, Chengdu University of Technology, Chengdu 610059, China.
Polymers
|July 15, 2026
Summary
A novel composite underlayment using recycled rubber, resin, and sand effectively reduces low-frequency impact sound in floating floors. This material offers superior sound insulation and long-term structural stability for residential applications.
Area of Science:
- Materials Science
- Acoustics Engineering
- Civil Engineering
Background:
- Low-frequency impact sound control is a significant challenge for floating floors.
- Conventional underlayments lack sufficient damping and deform over time, hindering stable sound insulation.
- Recycled materials offer potential for sustainable and effective acoustic solutions.
Purpose of the Study:
- To develop and characterize a composite floating floor underlayment for enhanced low-frequency impact sound control.
- To investigate the vibration attenuation and noise reduction mechanisms based on constrained layer damping (CLD).
- To evaluate the material's physical, mechanical, microstructural, and acoustic performance, including long-term stability.
Main Methods:
- Development of a composite underlayment using recycled rubber granules, polymer resin, and quartz sand.
- Systematic investigation of material properties: physical, mechanical (dynamic mechanical analysis), microstructure, and acoustic performance (impact sound pressure level).
- Full-scale field testing and long-term cyclic loading (3000 cycles) to assess structural compatibility and durability.
Main Results:
- Optimal processing achieved with 20 wt% binder and 50 mesh rubber granules, avoiding shrinkage cracking.
- Composite underlayment reduced low-frequency impact sound (below 250 Hz) by 3-5 dB compared to XLPE foam, improving overall insulation by 10.77%.
- Stable viscoelastic behavior (loss factor > 0.2) and a weighted impact sound improvement index (ΔLw) of 15 dB were recorded, with no long-term deformation.
Conclusions:
- The CLD-inspired composite underlayment provides effective low-frequency impact sound control.
- The material demonstrates superior long-term structural stability and durability in floating floor systems.
- This offers an innovative solution for impact noise mitigation in residential applications.
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