Masonry Dam
masonry dam
[′mās·ən·rē ‚dam]Masonry Dam
a dam whose main structural elements are made from masonry materials, without binders. In the practices of modern hydroengineering construction, a distinction is made between rock-filled (filled), semifilled, and dry-set stonework. Masonry dams are usually built as fixed dams, with passage of the water through spillways on the banks or, less frequently, in the body of the dam.
The basic materials for the body of a masonry dam are rubble (from quarries), pebbles, gravel, and rocky soil. The stone for the fill and the dry masonry should have sufficient strength and resistance to weathering, the effect of frost, and destruction by filtration. The best materials for fill are igneous rock (granite, syenite, diorite, and basalt) and sedimentary rock (solid limestones and dolomites, as well as quartzites). The dimensions and shape of the stone, as well as the methods of compacting the fill, are of crucial importance, since they influence the porosity of the fill, the amount of settling in the body of the dam, and the steepness of the slopes. Virtually all types of rock are suitable for use as the base of a masonry dam; pebbles and gravel, coarsegrained sands and clays, and compact loams may also be used.
The possibility of using local materials determines the economy of masonry dams and their wide use in various geographic regions.
REFERENCE
Grishin, M. M. Gidrotekhnicheskie sooruzheniia. Moscow, 1968.V. N. POSPELOV