Evaluation of the susceptibility of landslides and debris flows on Costa Rica's national road network: Analysis of a segment of the National Route 32

摘要

Costa Rica's National Route 32 has historically been exposed to landslides and other geohazards since the day it opened in 1987, being one of the country's most vulnerable roads and with a very high socio economic impact when closed to traffic. The susceptibility of landslides in cut slopes and debris flows in a critical segment of 30 kilometers of the National Route 32 was evaluated by LanammeUCR through methodologies that allowed determining that this segment presents a median to very high susceptibility to landslides and that almost 50% of the watersheds crossed by this critical segment present a high susceptibility to debris flows, with the associated impact on drainage structures such as culverts. LanammeUCR applied the critical angle method along the analyzed section in order to identify other locations susceptible to landslides. The model used to analyze the susceptibility to landslides was calibrated with historical data, confirming that landslides have occurred in recurrent sites, an aspect that will require special attention for the planning and execution of the possible solutions.