The Egyptian market’s demand for an efficient and economic retaining walls solutions, has significantly increased during the past few years.
   
With the varying conditions of adjacent soils / structures, the secant piles walls can be considered as one of the best solutions to handle / overcome such variance.

The secant piles wall consists of two types of piles:
   

• Primary piles: which are rotary drilled to the required level, but poured with plastic concrete (a mix of plain concrete and bentonite slurry), and no reinforcement is used.
  
  
• Secondary piles: which are rotary drilled to the required level (cutting through the edges of the primary piles), then installation of reinforcement and pouring of concrete is carried out in the same way as bored piles. The secondary piles are reinforced and designed to take the earth pressure and surcharges from adjacent streets and structures, while the primary piles are formed of plastic concrete to allow for the cutting of secondary piles, and at the same time creating an interlocking frontier to prevent ground water from seeping into the excavation side.  
   

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