Quantitative Analysis of the Debris Flow Societal Risk to People Inside Buildings at Different Times: A Case Study of Luomo Village, Sichuan, Southwest China

Debris flows, which cause massive economic losses and tragic of life every year, represent serious threats to settlements in mountainous areas. Most deaths caused by debris flows China occur buildings, the death toll is strongly dependent on time people spend indoors. However, role spent indoors quantitative analysis flow risk has been studied only scarcely. We chose Luomo village Sichuan atop a alluvial fan study influence temporal variation presence inside buildings societal risk. Two types days (holidays vs. workdays) two diurnal periods (daytime nighttime) were considered our evaluation model. A questionnaire survey was conducted for each family village, probability impact household calculated based average amount member house. The hazard simulated with FLO-2D obtain intensity run-out map return 2, 10, 50, 100 years. residents quantitatively probabilities occurrence, spatial impact, vulnerabilities people. results indicated that holidays always higher than weekdays, at night also much daytime, suggesting an important consideration. proposed method permits us estimates probable rural provides basis decision-making planning mitigation countermeasures.