Abstract: The present paper points out that studying three-dimensional effects is fundamental for the identification of technical solutions that will help to reduce scours downstream of a stilling basin. The works analysed by means of a physical model are characterized by a marked asymmetry from both the geometric and the hydraulic point of view; as this asymmetry may give rise to random phenomena of stream flow concentration, it can lead to the anomalous working of the stilling basin as well as deep scours in the mobile river bed. This erosion is reproduced in the model and the experimental study has led to variations in the design of the stilling basin that, through the elimination of concentration and asymmetry in the stream flow, have resulted in a drastic reduction in scours.

• Publication Date: 28-May-2020
• DOI: 10.15224/978-1-63248-122-1-10
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Abstract: Roller Compacted Concrete (RCC) Dam construction involves the placement of concrete in successive layers, whose thickness may vary in general between 30 and 45 cm. The surfaces of contact between layers are planes or joints of potential weakness for the material, giving the same anisotropic mechanical characteristics. The tensile strength and shear strength of the joint between layers are basic design parameters for the RCC dam project, particularly necessary to ensure the reliability of the structure against seismic loads. The present work describes a test method to determine the direct tensile strength of the joint between layers and experimental results are obtained with this method, corresponding to the test of joints made under different conditions of concreting.The conditions studied included the test of joints with and without cement mortar, made with different waiting times between layers. Waiting times were one minute (continuous concreting condition), 6, 12, 24 and 72 hours.

• Publication Date: 10-Dec-2017
• DOI: 10.15224/978-1-63248-122-1-11
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