Plunge Pool Scour Studies Using Cohesive Materials in a Hydraulic Model

  • Samuel R. Coran National Hydraulic Research Center University of the Philippines Diliman


Rocks in situ do not slump and the traditional technique of using loose gravel in the model consequently cannot give a good representation of scour patterns in the prototype. Thus, a refined modelling technique utilizing cohesive materials (a mixture of granular materials with a paste composed of clay binder, chalk powder, and water) to simulate the plunge pool geology is introduced. This technique is applied to the plunge pool scours investigations in a 1:100 hydraulic scale model of a spillway project for the purpose of defining an adequate flip bucket toe protection system. The methods, procedures, and results of the investigations are presented.