A Two-Phase Quantitative Assessment Process on Scour Potential of Bridge at Sandy Riverbeds

摘要

Bridges in Taiwan confront scour challenge induced by typhoons and storms. Based on economic consideration, a twophasernassessment process on the safety of bridge scour is proposed and served as a rapid/inexpensive inspection ofrnscour potential first and a detailed quantitative evaluation later. An in-situ visual inspection obtains its rating of scourrnpotential on each bridge. These bridges being identified with high ratings of scour potential are highlighted on therndetailed assessment list for further quantitative evaluation which consists of archive establishment of backgroundrninformation and scour scenario simulation. The archive includes reviewing the structural, geotechnical, hydrologic,rnand meteorological data of the chosen bridges with high scour potential which will be served as the input data for thernanalysis of scour simulation. Based on two resulting parameters from the analysis, the scour depth and representativernvelocity of the target bridge, a criterion for rating its scour potential and issuing an alert sign then is defined andrnmarked on a scour chart of bridge safety. The application of this proposed process is illustrated to a bridge located at arnsandy riverbed.