Resident subjective annoyance responses to combined road traffic and train-induced structure-borne noise: Effects of sound environment

While road traffic noise annoyance has been extensively studied, field-based dose-response data for the combined exposure to road traffic noise and train-induced structure-borne noise in urban residential buildings remain scarce, particularly under varying window conditions. An exposome field experiment was conducted with 96 residents in a real residential building in Guangzhou, China. Participants were exposed to three standardized noise conditions: road traffic noise with windows open; road traffic noise with windows closed; and train-induced structure-borne noise with windows closed. An inverse correlation was observed between road traffic noise annoyance and structure-borne noise annoyance under closed-window conditions, suggesting a trade-off in residents' annoyance allocation. Self-reported health status emerged as a statistically significant covariate, with participants reporting poorer health exhibiting consistently higher annoyance ratings across all noise conditions. These findings indicate that: (1) window configuration exerts a pronounced influence on both acoustic exposure magnitude and perceptual annoyance response to road traffic noise; and (2) dose-response relationships are acoustically and contextually specific, precluding direct extrapolation across noise sources or environmental settings. These results offer empirically grounded, quantitative evidence to inform evidence-based noise policy formulation and performance-oriented building design standards-particularly in urban environments characterized by mixed transportation noise exposures.