A breast wall is a low stone wall that is constructed at the hillside to support (retain) the natural bank of earth.
This wall standoff to protect a freshly cut or old surface of a natural hill face.
It is mostly considered in the area where there is the action of weather and rainwater flowing over the hill’s slope, to prevent the hill slides.
It also prevents slides of unreliable soils.
1.1. Uses of Breast Wall
a. It is used at the sides of the road to retain the face of a natural bank of earth.
b. It is used to retain natural earth at the bank of the rivers.
1.2. Design of Breast Wall
The breast wall requires more base width because of surcharge loading exerted by the earth. The height of the breast wall is not supposed to exceed 3 meters because there is a higher possibility of overturning and sliding.
The design of a breast wall is done based on the height of the wall required, the nature of the backing, and the slope of cutting.
Weep holes should also be provided at regular intervals to reduce the saturated earth pressure at the wall.
The breast wall is designed such that the line of pressure should be normal to the earth pressure or thrust.
i. It prevents the soil on a natural slope of embankment from sliding down due to the effects of weather like erosion, heavy rainfall, etc.
ii. It can also be used in hydraulic structures.
iii. It plays a great role to control natural disasters like a landslide, slope failure, etc to some extent.
iv. It is economical.
v. Local materials and manpower can be utilized to construct.
vi. It enhances the safety of road users.
i. It is difficult as well as risky to construct breast walls in hilly areas.
ii. As it is constructed on a steep slope, high chance of overturning and sliding.
iii. Maintenace and repair work is quite tedious.
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