Seismic assessment of a RC case study building using the Simple Lateral Mechanism Analysis, SLaMA, method

The seismic assessment of an existing structure is a complex procedure. In the eval-uation of the structural capacity,difficulties arise in the definition of the lateral resisting mem-bers, in the estimation of thelateral capacity from component to system level.The identificationof the local and global mechanisms,depending on the hierarchy of strengthat subassembly level, is achallengingtask. Nowadays, advanced numerical analysisprocedures, implemented in user-friendly commercial software, are commonly adopted in the current practice to over-come the difficulties in the use of non-linear analyses. Nevertheless, their accuracy strongly depends on the ability of the numerical model to capture all the probable failure mechanisms.To help the user in the assessment of the probable failure mechanism and to have a first esti-mation of the building lateral capacity,the Simple Lateral Mechanism Analysis (SLaMA) methodhas been recently developed and included in the NZSEE2016 guidelines. SLaMA is asimple and reliable “by-hand”tool to derive the local and global mechanism of a structural system and the corresponding capacity curve. This paperdeals with the application of the SLaMA toan existing RC building severely damaged during the Christchurch earthquake (2011, New Zealand).The lateral capacity of four 2D resisting systemswas assessed following the SLaMAmethod.Theresults of a refined nonlinear numerical model were used to assess theaccuracy and reliability of SLaMA.The good match confirmed that SLaMA can be a usefuland simpletool to have a first estimation of the building lateral response. It allows to identify the main structural weaknesses driving the user to the development ofmore refined nonlinear models