Debris-flow risk and impact on buildings: A case study of Rosayoc-Batán, Peru

This study presents a comprehensive risk assessment associated
with debris flows in the Quebrada Rosayoc, located in the district of
San Rafael, province of Ambo, Huánuco region, Peru. Debris flows,
characterized by their high velocity and mobility, pose a significant
threat to the population and infrastructure in the area. Therefore,
this study seeks to conduct a quantitative risk assessments (QRA)
to accurately estimate potential damage to structures and associated
economic losses. To achieve this objective, historical records of
events were collected based on the selected observation years. Additionally,
topographic, climatic, geological, and socioeconomic data
were integrated with fieldwork, laboratory testing, and numerical
modeling to simulate debris flows and assess building vulnerability.
One of the most significant contributions of this work is the
introduction of the debris-flow intensity index (DFI) as a metric to
evaluate the physical impact on buildings. This index not only provides
a measure of the physical impact that debris flows can have
on buildings, but also allows for the classification of damage into
four categories, ranging from minor damage to total destruction of
structures. Finally, the generated risk map, which integrates hazard
levels, impact intensities and vulnerability, constitutes a fundamental
tool for urban planning and emergency preparedness, facilitating
informed decision-making and the implementation of effective mitigation
measures.