impact of number of selected records on probabilistic seismic performance of offshore jacket platforms

Intensive seismic excitations might be considered as one of the most important loading cases imposed on offshore jacket platforms, especially for the ones located in regions of high seismic hazard. for evaluating probabilistic seismic performance of such intricate structures, incremental dynamic analysis (ida) could be employed as an efficient and applicable procedure. in order to conduct ida, appropriate suites of ground motions are required that can be selected bydifferent scenarios and methodologies. furthermore, due to 3-dimensional numerical models of jacket platforms with a lot of nonlinear structural elements time history analyses of these infrastructures are truly time consuming. hence, number of selected records can substantially change the computational costs of such assessments. this paper aims to study the effects of sample size of ground motions on probabilistic seismic performance of offshore jacket platforms. in thisprocess, ida has been performed considering a suite of 40 far field records (selected as explained in (abyani et al., 2017; baker et al. 2011)) to model the aleatoric variability of the records. to this end, a numerical model of the investigated jacket platform is created in opensees software.