|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
WALLAP is a powerful, fast and user-friendly program for analysing the stability of cantilevered and propped retaining walls. WALLAP is suitable for the analysis of both temporary works, such as sheet pile walls, and permanent works such as reinforced concrete diaphragm walls and contiguous bored pile walls.
Factors of safety are computed according to standard codes of practice while wall displacements and bending moments are calculated by a finite element analysis which models the actual sequence of construction of the wall. Earth pressures are calculated automatically from basic soil properties.
The strata profile consists of up to 40 soil types with hydrostatic or non-linear water pressure distributions. Surcharges may be applied and removed while struts and anchors may be installed and removed. The program is menu driven with context sensitive Help and on-line access to the comprehensive User Manual giving detailed guidance on data input and interpretation of results.
Methods of Analysis ( Top )
WALLAP offers two
separate types of analysis within the one program:
Limit Equilibrium Analysis
Calculation of Factors of Safety according to one of the
following methods:
Bending moment and Displacement Analysis
Modelling of the stage by stage development of forces and wall
movements as construction proceeds. The wall and soil
are modelled as a beam and springs. Two spring models are available:
Modelling the Construction Sequence ( Top )
The following types of
construction activity may be specified and combined in any order so
as to model the construction sequence:
Soil Properties ( Top )
A maximum of 40
different soil types can be defined including:
Soil strength is defined in terms of Ka, Kac, Kp, Kpc and cohesion.
There is a Help facility to derive Ka etc.. from soil, wall friction
and backfill angles.
Soil stiffness is expressed in terms of Young's modulus and Poisson's
ratio.
Optional soil properties include:
Struts and Anchors ( Top )
Struts or anchors can be installed at up to 40 levels and may be pre-stressed. Struts can also be removed after installation.
Water Pressures ( Top )
Hydrostatic or
non-hydrostatic Water Pressure Profiles may be defined on both sides
of the wall, to model a variety of complex conditions including:
Automatic water pressure balancing option. This offers
a convenient way of balancing water pressures at the toe of
the wall by assuming a linear variation of piezometric head between
the water levels either side of the wall.
Surcharges ( Top )
Surcharges can be applied at or below ground level on the active or passive side of the wall. All surcharges are defined over a rectangular loaded area. Ramp surcharges can be defined i.e. Surcharge magnitude may vary linearly with distance from the wall.
Loads and Restraints ( Top )