Spatial Mapping and Attribution of Wheelchair Users’ Accessibility Decay Under an “Ideal-Realistic” Scenario Comparison

Within the “15-min community life circle”, spatial accessibility of basic services is critical to ensuring social equity for people with disabilities. However, existing wheelchair accessibility assessments predominantly focus on static “origin-destination” node configurations, treating the road network as homogeneous and failing to capture how micro-level physical barriers induce macro-level accessibility decay through network connectivity transmission. This study addresses this gap by introducing an “ideal-realistic” scenario comparison framework combined with weighted edge betweenness centrality. This approach backward-traces resource accessibility loss to two dimensions of micro-level road-segment failure, namely topological function loss and service resource loss, shifting the analytical paradigm from resource configuration assessment to network connectivity diagnosis. Taking the central Xinhai Subdistrict of Lianyungang, China, as a case study, this paper constructs a dual-scenario network based on field-surveyed barrier data and establishes a two-dimensional measurement system centered on segment-level function loss and resource loss. The findings reveal that realistic physical barriers cause significant deprivation in wheelchair users’ access to life-circle services. Moreover, this decay is not homogeneously distributed but is highly contingent on the topological role of road segments, exhibiting observed spatial patterns such as skeletal network collapse, critical entrance blockages, and isolated terminal resource clusters. The analysis elucidates how micro-level physical barriers are propagated through spatial connectivity, offering a new perspective for understanding impedance dynamics in existing urban slow-traffic environments. The results can inform precision interventions in pre-standard neighborhood renewal: critical bottleneck segments provide spatial targets for prioritizing resource allocation and context-specific strategies across communities.