Sustainable reuse evaluation framework for coastal industrial living preservation of heritage buildings based on visual perception driven

The protection and sustainable reuse of global industrial heritage have long been a widely concerned topic in the international community, and its existence is evidence of industrial development in various countries throughout history. As a historically significant hydraulic industrial heritage building in the eastern coastal region of China, many of them are currently underutilized or deteriorating. Traditional evaluation methods often overlook the role of public visual perception in guiding their sustainable revitalization. This study proposes an "objective + subjective" comprehensive framework for evaluating the visual perception and reuse potential of 32 coastal water heritage sites in eastern China, with a focus on providing information for the living preservation of historical buildings. Objective analysis employed drone photography, digital twin modeling (to address occluded elements), and semantic segmentation (DeepLabV3 + model) to extract six key visual indicators: Green Vegetation Index (GVI), Water Surface Index (WVI), Sky Coverage (SKVI), Hard Surface (HVI), Building Visibility (BVI), and Other Artificial Structures (OVI). Subjective data on perceptual dimensions—space, color, texture, uniqueness, culture, history, aesthetics, and pleasure—were collected via video-loop surveys (120 students) and online questionnaires (3,840 respondents) using a 5-point Likert scale. Multiple linear regression revealed that scenic beauty scores were most strongly predicted by GVI (β = 0.28, p < .001), WVI (β = 0.34, p < .001), and BVI (indicative of preserved heritage character). In contrast, SKVI, HVI, and OVI had limited influence. Among the sites, 14 were classified as high visual quality (≥ 35/40), 7 as medium, and 11 as low. The findings provide quantitative evidence to support the preservation of hydraulic heritage buildings through visual-centered living, promoting their continued cultural use through the integration of blue-green infrastructure and improved spatial aesthetics. The proposed framework offers a scalable and practical tool for policymakers and designers to enhance both the visual quality and sustainable reuse potential of linear industrial heritage, contributing to broader cultural sustainability goals.