Input dataMM / KN

Project

Calculation title
Project no.
Designed / checked

Wall, domain and mesh

Retained wall height, H		mm
Model width behind wall		mm
Model depth		mm
Target mesh dx		mm
Target mesh dz		mm
Water-table depth		mm
Required action reduction		%

Coordinates use x = distance behind the wall and z = depth below retained ground. Effective wall pressure is reported; hydrostatic wall pressure is excluded.

Soil materials

Name	E kPa	ν	γdry	γsat	K0

EPS materials

Name	E kPa	ν	Density kg/m3

Horizontal soil layers

Top z mm	Bottom z mm	Material

Case 1: Existing condition

EPS zones may be left empty or added where they exist in the original condition.

EPS zones

x mm	z mm	Width mm	Depth mm	Material

Surface strips

x mm	Width mm	q kPa

Case 2: Proposed EPS condition

EPS zones

x mm	z mm	Width mm	Depth mm	Material

Surface strips

x mm	Width mm	q kPa

1 ORIGINAL SOIL / EPS + SURFACE STRIPS

2 PROPOSED SOIL / EPS + SURFACE STRIPS

Phase 1 theory and limits

Implemented model

A two-dimensional, small-strain, drained, linear-elastic plane-strain model of the retained ground behind a smooth rigid wall. Soil layers and rectangular EPS zones use conforming constant-strain triangular elements. The wall, far boundary and base are displacement boundaries; wall pressure is recovered from the solved horizontal wall reactions.

Initial effective stresses: σv0'(z) = ∫ γ' dz; σh0'(z) = K0 σv0'(z)

No Rankine or Coulomb pressure is applied to the wall. Surface strips, EPS weight and stress redistribution are assembled through the continuum model. The reported q3 is a smoothed, nonnegative action-equivalent profile recovered from the wall reactions; it preserves their total thrust and moment about the bottom of the retained wall.

Current scope

Horizontal soil layers and any number of axis-aligned rectangular EPS zones within the retained-side domain.
Equivalent-linear soil and EPS stiffness, self-weight, K0 geostatic stress and uniform surface strips.
Smooth rigid wall; perfect bond between soil and EPS; static loading; small strain.
The water table changes effective unit weight below its level. Hydrostatic pressure acting directly on the wall is not included.

Not yet modelled

Mohr-Coulomb yielding, non-associated plastic flow, tension cracking or a true active-state wall movement.
Compression-only opening/sliding at soil-wall and soil-EPS interfaces.
EPS nonlinear compression, creep, temperature effects, damage or buoyancy.
Construction history beyond the phase-one equivalent stress redistribution, three-dimensional effects, global slip-circle stability or seismic loading.

Use

This is an elastic/K0 sensitivity and comparison model. Check mesh and boundary sensitivity and independently verify results before engineering use. It is not a substitute for a validated nonlinear geotechnical FEM package or project-specific design assessment.

Run both cases to populate the calculation report.