Data: 25/07/2018 à 27/07/2018
Local: Porto Alegre-RS
Mais informações: https://www.abrh.org.br/iend
IDENTIFICAÇÃO DE ÁREAS PROPENSAS A ESCORREGAMENTOS TRANSLACIONAIS NAS BACIAS DO TABOÃO E MATADOR, RIO DO SUL-SC
3 - Previsão e mapeamento de movimentos de massa
Rio do Sul municipality, in Santa Catarina state - Brazil, hosts frequent and intense rainfall events, resulting in the recurrence of extreme events, as floods and landslides. Although both disasters account for economic and human loss, hydrologic driven landslides are underassessed in the region. Therefore, several studies took place in investigating the effects of rainfall in slope stability. On that basis, slope stability models combining hydrologic, pedologic and morphometric parameters emerged, not only to assess slope stability but also predict susceptibility areas. Recent studies have shown better and more consistent results when applying TRIGRS (Transient Rainfall Infiltration and Grid-Based Regional Slope Stability) model in comparison to traditional slope stability models. TRIGRS is a distributed model for shallow translational landslide susceptibility studies, which calculates the factor of safety for each pixel of a digital elevation model. The present study aimed to assess slope stability of Taboão e Matador rivers catchments, in Rio do Sul, with the application of TRIGRS model. The rainfall series used on simulations correspond to the extreme events occurred in September 8 and 9 of 2011. The model?s efficiency was evaluated through the rate between Success Index (Índice de Acerto - IA) and Error Index (Índice de Erro - IE). The simulation with the most satisfactory result had an initial water table depth of 105 cm, resulting in an IA/IE index rate of 6.62. The result indicates that rainfall data used on the simulations had good correspondence with the September 2011 landslide triggering events, being the main cause to landslide deflagration in that event.