Module 6 : Design of Retaining Structures
Lecture 29 : Braced cuts [ Section 29.4 : Failure Analysis Of Bracing Systems ]
   
  Once the stability against bottom heave and clay bursting are achieved, the next step is to ensure the structural stability of the braced excavation. These include the following:
Yielding of supports
  Due to earth pressure on both sides of the excavation pit, compressive stresses are generated on the struts. When this force increases beyond safety the struts may yield.
Excessive ground movements
 

Braced excavation is carried out in places where there is scarcity of place in the surrounding to make a stable inclined slope. Now during excavation as the earth is being removed the pit, the pressure of the foundations of the adjacent buildings tend to create pressure on the soil mass leading to the movement of the surrounding soil into the pit and there by the surrounding structures are distressed. The above phenomenon is more critical for a small structure in the vicinity than a large one.

 
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