Application	PLAXIS 3D
Version	PLAXIS 3D
Date created	23 October 2024
Date modified	23 October 2024
Original author	Richard WITASSE - Principal Application Engineer
Keywords	PLAXIS 3D, Soil improvement, Rigid Inclusions, Consolidation, Embankment

 

Rigid inclusions are a ground improvement technique used to enhance the bearing capacity and reduce the settlement of weak, compressible soils. This method involves installing high-modulus columns, typically made of concrete or grout, into the ground. These columns are significantly stiffer than the surrounding soil and help distribute loads more effectively.

This exercise deals with the 3D analysis of an 8 m high embankment constructed and stabilized with 8 m long rigid inclusions with a diameter of 0.38 m installed in a square pattern installed at 1.9 m spacing. The subsoil consists of three soft layers (1.5 m peat layer in between a 2.5 m and a 2 m alluvium layers). A stiff dense sand layer underlies the three top soft formations and extends to a depth of 20 m below the ground surface (see Figure 1).

 

Due to cyclic symmetry conditions in the out-of-place direction, only a slice, the width of which is equal to the spacing between the rigid inclusions, can be considered.