One- and Two-Dimensional Benchmark Results from Pacific Engineering and Analysis

A finite-source stochastic one-dimensional ground motion model, coupled to vertically propagating equivalent-linear shear-wave site response models was used to estimate the ground motions for the one- and two-dimensional benchmarks. This model has been validated for nineteen well-recorded earthquakes, M 5.6 to 7.6 at over 600 sites. Median peak accelerations ranging from 0.115 g (at station R01) to 0.218 g (at station R09) are estimated at the nine surface sites for the two-dimensional benchmark (S1 M6) from a non-linear analysis incorporating EPRI modulus-reduction and damping curves and parametric uncertainty. Median values of peak acceleration, velocity and displacement along with the16 th to 84 th percentile ranges in parenthesis at R05 are 0.14 g (0.109 to 0.184 g), 20.3.cm/sec (14.7 to 28.0 cm/sec) and 8.9 cm (5.3 to 15.2 cm). Corresponding values from the linear analysis are 0.22 g (0.165 to 0.293 g), 21.1 cm/sec (15.5 to 28.7 cm/sec) and 8.7 cm (5.1 to 14.8 cm). Median values of peak acceleration, velocity and displacement along with the 16 th to 84 th percentile ranges in parenthesis at R10 (at depth) are 0.072 g (0.057 to 0.090 g), 6.4.cm/sec (5.1 to 8.0 cm/sec) and 3.4 cm (2.5 to 4.7 cm). Median values of peak acceleration along with the 16 th to 84 th percentile ranges in parenthesis at R05 and R10 for the M 2.9 (W1) are 0.0124 g (0.0098 to 0.0156 g) and 0.0046 g (0.0041 to 0.0052 g), respectively.