Field Study on Wood Accumulation at a Bridge Pier

Transported large wood (LW) in rivers may block at river infrastructures such as bridge piers and pose an additional flood hazard. An improved process understanding of LW accumulations is essential for a risk assessment. Therefore, we conducted field study the River Glatt Zurich (Switzerland) to analyze accumulation single logs circular pier evaluate results previous flume experiments with respect potential scale effects. The test demonstrated that can be described by impact, rotation, separation phase. was combining two simplified equilibria acting forces moments, which are mainly function diameter, roughness, flow properties. We applied resulting analytic criterion data explain behavior 82% logs. In general, observations confirmed on probability laboratory, supports applicability laboratory studies investigate LW–structure interactions.