What is toe and heel in dam?
Basic definitions Toe and Heel: The toe of the dam is the downstream edge of the base, and the heel is the upstream edge of the base. Maximum base width of the dam: is the maximum horizontal distance between the heel and the toe of the maximum section of the dam in the middle of the valley.
Why are dams slanted?
This is because of the triangular distribution of the water pressure. The deeper the water, the more horizontal pressure it exerts on the dam. The slant on the upstream face in the third shape allows water to weigh down on the dam, increasing its stability.
What is stability of dam?
Therefore, the requirements for stability are, The dam should be safe against overturning. The dam should be safe against sliding. The induced stresses (either tension or compression) in the dam or in the foundation should not exceed the permissible value.
How does an arch dam work?
The arch dam is an impressive structure which is curved upstream and uses hydrostatic pressure to transfer the force of water to the foundation and abutments of the dam. The force of the water on the fill side pushes against the arch, and the resulting resistance to bending transfers the loads to the abutments.
What is tail water in gravity dam?
Tailwater refers to waters located immediately downstream from a hydraulic structure, such as a dam (excluding minimum release such as for fish water), spillway, bridge or culvert. Failure of a dam or hydraulic structure will dramatically increase the tailwater level.
Are dams hollow?
Hollow gravity dam. A dam constructed of concrete and/or masonry on the outside but having a hollow interior relying on its weight for stability. Crib dam. A gravity dam built up of boxes, crossed timbers, or gabions filled with earth or rock.
Are dams natural or manmade?
A dam is a man made barrier usually built across a river to hold back water and forming a lake, or reservoir, behind it.
What is overturning in dam?
Overturning Failure of Gravity Dam: If the resultant of all the forces acting on a dam at any of its sections, passes through toe, the dam will rotate and overturn about the toe. This is called overturning failure of gravity dam.
How do you stop a dam from sliding?
The most common methods for rehabilitation of gravity dams that do not meet stability criteria include buttressing or anchoring. Buttressing consists of adding mass to the downstream portion of the structure to resist sliding. This can be accomplished using conventional mass or roller-compacted concrete.
What is the world’s tallest dam?
Nurek Dam
World’s Tallest Dam Currently, the tallest dam in the world is Nurek Dam on the Vakhsh River in Tajikistan. It is 984 feet (300 meters) tall. Hoover Dam is 726.4 feet (221.3 meters) tall.
What is a tailwater ditch?
[′tāl‚wȯd·ər ‚dich] (agriculture) A channel made along the lower end of a field to carry surface runoff from irrigation furrows off the field.
