Köprü kenar ve orta ayakları arasında yerel oyulma ile ilgili etkileşim

Flowing water usually causes transportation of loose non-cohesive materials, called sediment in literature, in natural open channels such as rivers and canals with a transportable material bed. This sediment transportation is observed in two different situations; deposition and erosion. Excessive erosion leads in scouring. Scouring can be classified in three groups; general, contraction and local scour. Scouring namely removal of bed material from bridge sites causes bridge failures. Hence, estimation of scour depth around bridge piers and abutments is essential for safety and economic design in alluvial rivers. Although local scour around bridge piers and abutments has been studied separately by a large number of investigators, there is almost no research in the literature related to interaction between these two structures. Hence, in this study the aim is to investigate the interaction between bridge abutment and pier scours in detail. For this reason bridge abutments and piers of different sizes were placed at various distances from each other in a long sediment channel and tested under clear-water flow conditions with a constant flow intensity. After conducting sufficient number of tests, the related experimental data were obtained. All the important dimensionless parameters involved in the phenomenon were derived from dimensional analysis and the relationships between them were investigated. The analysis of the available data showed that the presence of pier(s) in the flow medium in addition to an abutment has a certain amount of influence on the formation of scour holes around the structures. The relations between the dimensionless scour parameters and related dimensionless independent parameters were determined graphically. A series of empirical equations were derived to estimate the scour parameters around the pier-abutment arrangements consist of one pier-one abutment and two piers-one abutment cases.