Geospatial Decision Support for Vacant-Land-Based Tertiary Hospital Siting: Pareto Enumeration of Multimodal Accessibility–Equity Scenarios in Beijing

Equitable access to tertiary healthcare contributes to sustainable urban development. We develop a geospatial decision-support framework to evaluate vacant-land siting of tertiary hospitals in Beijing and its implications for potential accessibility and spatial equity. Existing work has not jointly enumerated all combinations in a finite candidate set and compared aggregate results with district-level disparities. Using data for 13,109 residential communities, 82 existing tertiary hospitals, and 23 candidate parcels, we enumerate every combination of one to five new sites. S1–S5 denote scenarios with one to five sites, respectively. We use the published multimodal accessibility model, collect route costs for candidate-site–community pairs, estimate candidate-hospital staffing from parcel area using a linear regression calibrated on existing hospitals, and assess population-weighted accessibility and the Gini coefficient. Pareto fronts identify non-dominated combinations; an equal-weight normalized ideal-point rule selects compromise solutions. The five scenarios contain 23, 253, 1771, 8855, and 33,649 combinations, with 2, 6, 8, 10, and 13 non-dominated solutions, respectively. The tied one-site compromises, S1-A at site 16 and S1-B at site 19, increase weighted accessibility by 8.88% and 3.37%, while Gini changes by +0.84% and −0.48%, respectively. S2–S5 increase weighted accessibility by 12.61–29.02% and reduce Gini by 0.01–0.85%. These are model-based scenario estimates, not implemented or empirically validated siting outcomes. The framework can inform other urban facility-location analyses when local data and accessibility models are adapted.