Structural Response Sensitivity to Rupture Parameter Variations: A High-Fidelity Analysis of a 10-Story Building on the San Ramón Fault

My student Patricio Palacios B. is presenting this work this week at PBD-V 2026, the 5th International Conference on Performance-Based Design in Earthquake Geotechnical Engineering, in Puerto Varas, Chile (4–6 November 2026). Co-authored with Nicolás Mora Bowen and myself, the paper asks a question that matters a lot for near-fault design: if you only run one rupture scenario for a given magnitude, how wrong could your structural demand estimate be?

The answer, from a campaign of 72 soil-structure interaction analyses: quite wrong, close to the fault. We generated stochastic finite-fault ground motions for Mw 6.5 and Mw 6.6 scenarios on the San Ramón Fault (three stochastic realizations each), propagated them into a 10-story reinforced-concrete building through the Domain Reduction Method at three sites spanning 3.3 to 22.5 km from the fault, and ran a three-factor ANOVA at every floor to disaggregate response variance into magnitude, stochastic slip distribution, and source-to-site distance. Source-to-site distance dominates (60–95% of variance), but at the nearest station, inter-realization displacement differences exceed 100% — a single deterministic scenario just isn't enough to characterize near-fault structural demand.

Explore the model in 3D

Patricio built a full interactive explorer of the fault, the ground motions, the soil domain and the building response — it runs right in your browser, phone included.

🌋 Open the interactive explorer →

The San Ramón Fault model and recording sites, one of eleven chapters in the interactive explorer.

Scan to open on your phone — handy if you're at the conference.

Citation: Patricio Palacios B., Nicolás Mora Bowen, José A. Abell. Structural Response Sensitivity to Rupture Parameter Variations: A High-Fidelity Analysis of a 10-Story Building on the San Ramón Fault. 5th International Conference on Performance-Based Design in Earthquake Geotechnical Engineering (PBD-V), Puerto Varas, Chile, 2026. Read the paper (PDF)