Paratie – Non linear spring analysis of retaining walls

One of the main purposes of Paratie Plus is the analysis of the behaviour of flexible earth retaining walls.

As widely recognized, lateral movements, bending moments, shear forces in walls as well as reactions in lateral supports are significantly affected by the construction sequence.

For most design situations such aspect can be easily studied by the nonlinear spring engine Paratie included in Paratie Plus.

The nonlinear spring method is an engineering approach to model soil-structure interactions, not requiring complex finite element meshes or advanced constitutive models for soils.

The non linear spring scheme

The soil is modeled by special springs, which include most nonlinearities of actual soils.

The walls are modelled through ordinary flexible beam elements.

Lateral supports are simply modeled as linear or non linear springs as well.

Soil resistance can be either described through ordinary Mohr-Coulomb parameters c’ and φ’  or via active and passive thrust coefficients Ka and Kp.

A special model is provided to model fine soils under undrained conditions.

The stiffness of nonlinear springs  is automatically computed by Paratie based on secant  soil moduli, and is modified at each analysis stage.

Pore pressures, if any, can be directly estimated by Paratie or seamlessly imported by a more rigorous seepage analysis.

Special features not easily available by other programs

A special element to model retaining walls with internal slippage (such as Larssen sheetpiles).

See details…

 

The possibility to model plastic hinges in retaining walls

 

The modelling of facing walls connected by struts or slabs or a sheetpiles wall and anchor wall together in the same model

 

   A pseudo-static seismic procedure for both rigid and yielding walls

See reference…

  A special procedure to model coupled walls interacting through a non linear contact logic.