Lane's Relation in Local Scour Investigations

Abstract

Alluvial river channels undergo transformations due to fluvial processes such as water flow which invokes soil particles movement. Mentioned processes are interrelated and can be described as a feedback relation which means that hydraulic and morphological features adjust to each other during the process of obtaining the dynamic balance between water flow and sediment transport intensity. The dynamic balance phenomenon was described qualitatively by Lane (1955). Local scour can form in the riverbed as a result of a dynamic balance loss. Despite considerable scientific research in various physical model cases and a wide range of hydraulic and ground conditions, universal guidelines of scour shape properties calculations remain unknown. Therefore, a more extensive investigation of the phenomenon is needed. The paper proposes an empirical model based on Lane's relation, that allows to obtain functional correlation and which can be used in local scour basic geometry properties description formed in an alluvial flume with sandy bed, in steady flow conditions, using various water structure models. A device, made by the Authors, equipped with a laser scanner was used for bed investigations.