Clay-cement concrete diaphragm of the type "slurry wall" in the 100 meter high dam

• Main Authors: Radzinskiy Aleksandr Vladimirovich, Rasskazov Leonid Nikolaevich, Sainov Mikhail Petrovich
• Format: Article
• Language: English
• Published: Moscow State University of Civil Engineering (MGSU)
• Series: Vestnik MGSU
• Subjects: diaphragm; diaphragm strength; headrace; downstream; reliability coefficient; clay-cement concrete; stability; stress-strain state; tensile strength
• Online Access: http://vestnikmgsu.ru/files/archive/issues/2014/9/ru/12.pdf

In the article the authors estimate the possibility of building a high (100 m high) stone dam with clay-cement concrete diaphragm. This diaphragm is used as an antifiltering element and it is made of secant piles method of clay-cement concrete (method of "slurry wall"). This diaphragm should be constructed in several phases, in our example example in three stages. Numerical studies of the stress-strain state of such a dam show that considerable compressive stresses can appear in the diaphragm. These stresses can be significantly (3...4 times) greater than the strength of clay-cement concrete in compression. However it should be taken into consideration that the diaphragm of such a high dam will be crimped by horizontal stresses, i.e. clay-cement concrete will operate in the triaxial compression. Under these conditions the strength of clay-cement concrete will be significantly higher, therefore, the diaphragm reliability might be provided with a margin. For this reason, the most important issue in the engineering of a high dam with such type of diaphragm is to select the required composition of clay-cement concrete. Increasing its strength by extension of the cement fraction could increase modulus of deformation. Therefore it could lead to compressive stress increase and the strength state degradation. Hydrostatic pressure generates the areas of tensile stresses in the clay-cement concrete diaphragm due to the arising bending deformation. It threatens the formation of cracks in the clay-cement concrete, especially in the nodes interface diaphragm queues. It is recommended to match the diaphragm queues using ferroconcrete galleries. This should ensure flexibility of deformation between the gallery and the diaphragm.