Validation of Bridge Scour HEC RAS Model Using Propagation Error Analysis

The scouring phenomenon is one of the causes of bridge damage in the world. This scouring phenomenon has various kinds such as local scour and contraction scour. There are various equations for calculating pier scouring, including Colorado State University equations, Frochelin and others. A computer program is needed to facilitate the calculation of pier scouring, HEC-RAS based on Finite Difference Method was chosen to simulate pier scouring problem. Up until now, there has not been any research to quantify the uncertainty of bridge scour HEC RAS based of experiment. The objective of this study to validate the pier scouring calculation by comparing the expected value of pier scouring results of HEC-RAS with an experiment and CSU equation. The HEC-RAS was evaluated using experimental data that had been carried out by Shukri in 2017. Furthermore purpose of this study is determining which the variable that is sensitive to the depth of scouring. The sensitive variables are determined by performing sensitivity analysis of the variables on HEC-RAS using the Pearson correlation coefficient method and regression analysis. Error propagation is done to get the uncertainty value from pier scouring due to the influence of sensitive variables.