Joint Probability Modeling for Two Debris-Flow Variables: Copula Approach

This paper presents joint probability modeling for debris flows' maximum impact pressure and total sediment discharge through the use of the copula theory that has been proven useful to joint probability modeling. On the basis of the data from the Jiangjia Ravine of southwestern China, the study calibrates and proposes a copula model for simulating their joint probability distribution with statistical significance, or the model was statistically accepted based on goodness-of-fit testing. With the bivariate copula model, a more accurate reliability-based design for constructing debris-flow barrier structures in the study area is feasible, considering the two variables and their dependency simultaneously as it should be.