Evaluation of Convenience of 15-Minute Community Life Circle Facilities and Analysis of Non-Linear Influencing Variables from the Perspective of Aging: A Case Study of Shenyang

Amid rapid global population aging, developing age-friendly urban spaces centered on the “15-minute community life circle” has become a priority in planning research. Taking Shenhe District of Shenyang City, a region undergoing deep aging, as a case study, this research constructs a facility weighting system reflecting the actual needs of the elderly. Integrating multi-source spatial data, the XGBoost model and SHAP framework were applied to analyze the non-linear effects of socio-economic, functional, and land-use factors on facility convenience. Results indicate that: (1) facility convenience exhibits a distinct “west-high, east-low” spatial pattern, characterized by high agglomeration in the western core and significant deficits in the eastern fringe; (2) convenience levels vary across categories, with medical and health facilities showing the highest accessibility, while cultural and leisure (CALFs), life service, and elderly care service facilities (ECSFs) remain the primary deficiencies; and (3) influencing variables demonstrate complex non-linear mechanisms, wherein functional density and distance from the city center are critical drivers with non-monotonic effects, while road network density displays threshold effects, inhibiting ECSFs and CALFs at high densities. These findings provide a refined, quantitative basis for optimizing facility layouts and formulating urban renewal strategies to build age-friendly communities.