| Abstract: | Evaluating the earthquake safety of existing structures – the risk‐based approach of the Swiss Recommendation SIA 2018. Earthquake actions to be considered in the design of new structures increased considerably with every code generation published in Switzerland over the past few decades. Especially older structures, however, do not comply with actual code requirements and might be judged insuffient. Upgrading existing structures is very costly and asking all existing building stock to meet actual code requirements would leave us bankrupt. Clearly, existing structures cannot be evaluated by applying current code requirement. An expert group appointed by the Swiss Society of Engineers and Architects (SIA) therefore worked out a risk‐based concept for the evaluation of existing building stock with respect to earthquake hazards. Additional key terms are a compliance factor linking the strength of the structure under consideration to the current codes for new structures. In case this factor is lower than some threshold the commensurability and reasonableness of implementing a possible remedial measure is judged by checking the measure against a fixed threshold value of the associated life‐saving costs . In case commensurable and reasonable measures cannot be found it is recommended to accept existing risks also in the future. |
