Cut Stability Analysis

Data file: tutorials/cut.inp

Description of the problem.
The objective of this lesson is to get familiar with the Z SOIL environment, in particular with the graphic object-oriented preprocessor and post-processor. In this tutorial a macro-modeling approach, with semi-automatic meshing, will be used.


Engineering draft
The geometry of a 4 meter-high cut is shown in the figure below.

Project preselection
In the dialog box for project preselection (it appears automatically for option File/New in main ZSoil menu) set Plane strain to ON and select Deformation item from the Problem type list. This way a single-phase, plane strain analysis is to be carried out.


Drivers
In ZSoil program drivers list contains an information what is to be computed by the calculation module and in which order. In the geotechnical engineering to obtain correct results all major steps like excavation, stage construction, modi cation of the boundary conditions for solid and fluid must be taken into account and must reproduce all events as in the reality.
To set up the list of drivers use menu Control/Analysis & drivers. From list of drivers select Stability, from list Type select tan()-c reduction algorithm, specify the initial value of the safety factor, its nal value and increment and accept the setting with button Modify (note that the default driver is always set to the Initial state and for that reason it must be modifi ed in our case).

 


In the considered case computation will start with the SF factor equal to 1.0, then 1.05, 1.10 etc… until divergence occurs (loss of stability is detected) or fi nal value of the safety factor is achieved.
To learn on how to set up drivers list watch the video

Materials
In this example a single material, described by the Mohr-Coulomb elastic-perfect plastic model, is used. The material properties are given in the following table.

To edit material properties use menu Assembly/Materials.
To learn on how to enter material data watch the video.

Summary of all data preparation steps (video films)
Create a new project
Create macro-model
Create meshes in subdomains
Create solid boundary conditions
Edit materials
Set drivers
Run computation
Visualize results