Author(s): Matteo P. E. A. Federspiel; Erik F. R. Bollaert; Anton J. Schleiss
Linked Author(s): Anton J. Schleiss
Keywords: No Keywords
Abstract: Dam flood release structures generate high-velocity plunging jets. These jets may erode the downstream rocky riverbed and may endanger the dam foundation. Assessment of the scour extent in fractured rock is essential to ensure the safety of the dam and appurtenant structures, as well as to guarantee the stability of its abutments. In the framework of a research project, an experimental set-up has been designed and constructed to measure the response of an artificial rock block impacted by a high-velocity jet. The set-up allows simulating near-prototype jets in view of velocities, turbulence and aeration. The real rock block is simulated by use of an artificial ( “intelligent” ) block equipped with pressure and displacement transducers as well as an accelerometer, and embedded in an artificially created surrounding rock mass. Its behaviour under high velocity jet impact has been systematically studied. The “intelligent” block is separated from its surroundings by 1 mm thick joints, which are equipped with pressure transducers along the vertical and horizontal faces. Two types of jet impact have been investigated: core jet impact and developed jet impact. The tests are performed for varying plunge pool water levels and varying jet velocities. Data analysis focuses on the relationship between the water pressures acting around the block and the dynamic behaviour of the block. The paper presents the characteristic movements (displacement, acceleration and velocity) of the block as a function of the dynamic pressures around the block under symmetrical jet impact.
Year: 2010