Why is the gravity dam a triangular shape?

The shape of the gravity dam resembles a triangle. 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 the shape of elementary profile of a gravity dam?

Detailed Solution. The elementary profile of a dam subjected only to external water pressure on the upstream side will be a right-angled triangle, having zero width at water level and a base width (B) at the bottom, i.e., the point at which maximum hydrostatic pressure acts.

Which type of dam usually has a triangular profile and can resist the forces by its own weight?

gravity dam
Which type of dam usually has a triangular profile and can resist the forces by its own weight? Explanation: A gravity dam is a solid masonry or concrete structure, generally of a triangular profile, which is so designed that it can safely stand against a pre-calculated volume of water by virtue of its own weight.

What are the cases for which design of gravity dam is to be checked?

The design of a gravity dam should be checked for two cases, i.e., 1) Reservoir Full Case, and 2) Reservoir Empty Case. When the reservoir is full, the major forces acting are: weight of the dam, external water pressure, uplift pressure, and earthquake forces in serious seismic zones.

What is the advantage of gravity dam?

Advantages of Gravity Dams The gravity dams possess the following advantages: These are more suitable in steep valleys where earth dams may tend to slip. In these dams, surplus water may be discharged through the sluices provided in the body of the dam or over spillway built in a suitable location of the dam.

How does a gravity dam work?

A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation to oppose the horizontal pressure of water pushing against it.

Which of the following soil materials is most preferred for the central core material of zoned embankment type dam?

Which of the following soil material is most preferred for the central core material of zoned embankment type dam? Explanation: Clay shrinks and swells and is highly impervious is not suitable. It is sometimes mixed with fine sand or fine gravel so as to make it a suitable material for the impervious central core.

What are the forces acting on gravity dam?

External Forces Acting on Gravity Dam. Water Pressure. Uplift Pressure. Earthquake Forces.

Which outline is preferred for weak rocks?

Explanation: In self-supporting and strong rocks, either, D-shape or horse-shoe shape may be conveniently adopted but these shapes would be practically unsuitable in soft ground or even in weak rocks with unequal lateral pressure. In those cases, circular outline may be the first choice.

Which condition is the most Favourable at the site of the dam and reservoir?

Generally a dam site is ideal where a valley is constricted with steep rock slopes. A narrow stream flowing between high, rock walls would naturally suggest a concrete overflow dam whereas a low, rolling plain would suggest an earth-fill dam.

What are the advantages of gravity dam?

Advantages of gravity dams.

• Gravity dams are relatively more strong and stable than earth dams.
• Gravity dams are well adapted for use as an overflow spillway crest.
• They can be constructed of any height, provided suitable foundations are available to bear the stresses.

In which situation is the gravity dam required to be strengthened?

Earthquakes are the biggest danger to gravity dams and that is why, every year and after every major earthquake, they must be tested for cracks, durability, and strength. Although gravity dams are expected to last anywhere from 50–150 years, they need to be maintained and regularly replaced.

Why do dams have right angled profiles?

Therefore the dam is subjected to horizontal water pressure at the upstream face and uplift pressure at the base. In such case a right angled triangular profile as shown in Figure 32.1, provides the maximum possible stabilizing force against overturning, without causing tension in the base.

How to determine the elementary profile of a gravity dam?

While determining the elementary profile of a gravity dam only pressure due to water is considered. Therefore the dam is subjected to horizontal water pressure at the upstream face and uplift pressure at the base.

What are the forces acting on a gravity dam?

Gravity Dams Forces Acting on Gravity Dam • The Various external forces acting on Gravity dam may be: • Water Pressure • Uplift Pressure • Pressure due to Earthquake forces • Silt Pressure • Wave Pressure • Ice Pressure • The stabilizing force is the weight of the dam itself 9. Gravity Dams 10.

What is the basic profile of a hydro dam?

Welcome back. and 2 others joined a min ago. Elementary profile of a dam subjected only to external water pressure on upstream side, will be right angled triangle, having zero width at water level and a base width (B) at bottom, i.e., the point at which maximum hydrostatic pressure acts.