Trabajo de grado - Maestría
Stability of a permeable obstacle against the impact of a water flow
Fecha
2022-06-17Registro en:
instname:Universidad de los Andes
reponame:Repositorio Institucional Séneca
Autor
Cote Martínez, Laura Valentina
Institución
Resumen
Baffle mitigation structures can be built from permeable obstacles with non-fixed bases, leaving the question of how easy it is for these structures to slide. In this master thesis, we study the stability of permeable obstacles against a water flow in a planar configuration. It has been previously studied gabion weirs permeability with fixed base and in the steady-state condition. Also, the impact of mass flows against solid obstacles has been studied. However, the study of permeable obstacle impact is still insufficient. Here, we try to characterize the interaction between a water flow impacting a permeable obstacle, varying its height H and width B.The obstacle velocity and displacements, as well as, flow kinematics are measured through digital image analysis. The normal and tangential forces are measured with leaf springs. Additionally, We propose a simple analytical model for describing the interaction of a flow impacting permeable obstacles. We evaluate the efficacy of this model with the experimental setup.
It is shown that the obstacle aspect ratio (H/B) affects the obstacle stability, where smaller aspect ratios tend to be more stable. It is identified that the transition between flow through and overflow is a trigger for instability, and this characteristic time is useful for characterizing the obstacle stability. Our results demonstrate that the permeable obstacle interaction with a water flow, results in five possible outcomes: stable, stable-slide, slide, slide-overturn, and overturn. This study provides a useful set of observations of permeable obstacle stability in terms of obstacle aspect ratio.