Research on Technical Strategies for Indoor Acoustic Renovation of Multi-Purpose Gymnasiums: Scheme Demonstration and Engineering Practice Based on Existing Sound-Absorbing Ceilings

Multi-purpose gymnasiums are typically designed for sport events and large-scale gatherings. However, the gymnasium investigated in this study lacked sufficient consideration of acoustic performance during its design phase, resulting in severe echo problems, long reverberation time and poor speech intelligibility. These acoustic deficiencies limit its ability to host major events, reduce utilization efficiency and cannot be resolved by simply adjusting the sound reinforcement system. Conventional renovation strategies usually involve sound-absorbing materials on walls or ceilings, which are costly, labor-intensive and time-consuming. The case gymnasium discussed in this study has the particular advantage that its ceiling structure already provides partial sound absorption. To lower renovation costs and minimize construction workload, this research builds upon the existing ceiling structure and evaluates five renovation schemes through comparative analysis, proposing a renovation approach that remains economical while providing substantial performance benefits. The study calibrates the acoustic model through comparison between measurement and simulation in ODEON V16.0 software, and the validated model was further used to predict acoustic parameters under full occupancy across different schemes. Post-renovation field measurements confirm the reliability and accuracy of the proposed approach, offering a valuable reference for similar gymnasium acoustic retrofitting projects.