Question

Bonding crescent shaped earthen embankment in level tennis bere
than the construction of large dams across the rise to store water
Analyse this statement with their efects​

Answer 1

Answer:

Hydrologic and Hydraulic Design of Earthen Embankments

Earthen embankments play a major role in watershed planning and management. In this section, the design of small earthen embankments viz., tank bunds -which are very useful in watershed management, is discussed.

14.1.1 Tank Bunds

Tank bund is an embankment of low height. Generally it is made of earth. Since earth of various types is available, tank bunds may be constructed using principles adopted for construction of earth dams. Generally three types of tank bunds are constructed. They are:

(a) Homogeneous Tank Bund (Type A): Uniform and homogeneous materials are used in the construction of these type of earthen embankments. It is constructed with relatively flat side slopes from the consideration of stability. Most of the bunds belong to this type [Fig. 14.1].

Fig. 14.1

Fig. 14.1. Homogeneous Tank Bund (Type A).

(Source: Patel and Shah; 2008)

When the height of tank bund is more than 5 m, the section is modified suitability with seepage checking trenches, blankets, toe drains etc. s need to be applied

(b) Zoned Tank Bund (Type B): When earth of different types is locally available the bund may be constructed by dividing the section in different zones [Fig. 14.2].

Outer zone is generally made of pervious material indicated as ‘P’ in Fig. 14.2. The inner zone is made of impervious material. It is indicated as ‘I’ in the same figure.

Fig. 14.2

Fig. 14.2. Zoned Tank Bund (Type B). (Source: Patel and Shah; 20080

(c) Diaphragm Type Tank bund (Type C): Many times zoning is done by providing a central core wall, called diaphragm. It is generally constructed with masonry or concrete [Fig. 14.3].

Fig. 14.3

Fig. 14.3. Diaphragm Type Tank Bund (Type C).

(Source: Patel and Shah; 2008)

In such types of tank bunds, the diaphragm is taken quite deep into the foundation preferably up to the impervious stratum.

Design of Tank Bunds

Although high tank bunds are designed on the principles similar to design of earth dams, low tank bunds are constructed using empirical dimension. Commonly adopted bund