Recent catastrophic earthquakes have further highlighted the crucial need to develop and implement a medium-long-term national plan of seismic risk reduction in most of the seismic-prone countries worldwide. However, the constraint of economic resources and the lack of a prioritization plan are often deemed as primary obstacles to the practical implementation of such project. Moreover, when dealing with existing buildings, the technical complexity is further increased by building knowledge, often limited thus leading to higher uncertainty. To overcome this issue, improved and adaptive assessment procedures and tools should be developed. Following this goal, this paper presents a multi-knowledge level seismic assessment procedure based on the analytical-mechanical SLaMA (Simple Lateral Mechanism Analysis) method. An effective and supporting tool is developed to rapidly estimate the seismic safety and the socio-economic consequences/impact of buildings based on the data collected through assessment forms. An application of the SLaMA-based procedure is presented for a case-study building. Alternative scenarios are involved by assuming different data acquisition (knowledge) levels, from limited to complete. The range/domain of expected capacity curves, safety indexes and risk classes for all scenarios are identified. Results confirm the effectiveness of the proposed methodology and its possible implementation for seismic risk assessment studies at national scale
