From field to framework: integrating UN-Habitat guidelines for accelerated visual damage assessment and seismic vulnerability analysis after Myanmar’s 2025 Mw 7.7 earthquake

On 28 March 2025, a devastating Mw 7.7 supershear earthquake struck Myanmar along the Sagaing Fault, severely affecting Sagaing, Mandalay, and Naypyitaw. This study presents a Rapid Visual Assessment (RVA) of 1,556 residential buildings using UN-Habitat Level-1 and Level-2 evaluation forms. Results showed that 53.7% of buildings were classified as unsafe (Red), 21.2% required restricted use (Orange), and only 25.1% were safe (Blue). Structural vulnerability was strongly associated with building typology, particularly complex multi-story buildings with basements such as 6U-4L-2B and 4U-4L-3B, which recorded the highest Damage Severity Index (DSI) values. Common failure modes included soft-story collapse, foundation failures, column shear cracking, and frame joint damage. The study introduces a unified framework integrating DSI scoring with UN-Habitat placard outcomes, providing valuable insights for seismic risk mitigation, retrofitting strategies, emergency response, and urban resilience planning in Myanmar’s high-risk seismic regions. The findings underscore the importance of seismic design and construction quality.