Simplified pushover-based seismic loss assessment for existing infilled frame structures

Loss assessment is becoming a more familiar instrument in the seismic performance assessment of existing structures. Different approaches exist with varying degrees of complexity. The most notable is the component-based approach implemented within the FEMA P-58 guidelines. Despite recent research developments, practitioners must be provided with tools to conduct building-specific loss assessments simply and accurately. A simplified alternative to computationally intense component-based loss assessment is via storey-loss functions (SLFs). They reduce computational effort by describing a building typology's expected repair costs directly as a function of structural demands typically available to engineers, circumventing many steps of damage state and repair cost estimation for each individual damageable element in the structure. This study presents a pushover-based approach to estimate economic losses intended for practical application. It is implemented within a previously defined framework for simplified pushover-based seismic risk estimation via seismic hazard and vulnerability approximations. This additional simplification of direct losses utilises SLFs with structural response parameters like peak storey drift and peak floor acceleration. The steps required to apply the proposed approach are demonstrated via a case study application to infilled reinforced concrete frame structures. The method’s accuracy is appraised via a comparison with other simplified loss assessment methodologies currently available. It is seen that when taking the more rigorous component-based approach as a benchmark, the proposed approach exhibits excellent accuracy and robustness compared to existing methodologies of this sort, paving the way as a candidate to adopt in future codes and guidelines.