The Seismic Performance of Earthen Historical Buildings in Seismic-Prone Regions: The Church of Santo Tomás de Aquino in Rondocan as a Complex Example

Adobe churches are representative of Andean architectural heritage, yet their structural
vulnerability to seismic events remains a significant concern. This study evaluates the seismic
performance of the 17th-century Church of Santo Tomás de Aquino in Rondocan, Peru, an
adobe building that underwent conservation work in the late 1990s. The assessment combines
in situ inspections and experimental testing with advanced nonlinear numerical modeling. A
finite-element macro-model was developed and calibrated using sonic and ambient vibration
tests to replicate the observed structural behavior. Nonlinear static (pushover) analyses were
performed in the four principal directions to identify failure mechanisms and to evaluate
seismic capacity using the Peruvian seismic code. Kinematic limit analyses were conducted
to assess out-of-plane mechanisms using force- and displacement-based criteria. The results
revealed critical vulnerabilities in the rear façade and lateral walls, particularly in terms of
out-of-plane collapse, while the main façade exhibited a higher capacity but a brittle failure
mode. This study illustrates the value of advanced numerical simulations, calibrated with
field data, as effective tools for assessing seismic vulnerability in historic adobe buildings. The
outcomes highlight the necessity of strengthening measures to balance life safety requirements
with preservation goals.