Constant Field Stress
The Constant field stress option is used to define a constant stress field prior to excavation (i.e. one which does not vary with position or depth). Constant field stress is typically used for excavations which are relatively deep (i.e. not close to the ground surface).
In the Field Stress dialog, the following parameters are used to define a Constant field stress.
Sigma 1
Sigma 1 is the major principal field stress.
Sigma 3
Sigma 3 is the minor principal field stress.
Sigma 2
Sigma 2 is the intermediate principal field stress.
Orientation
The Orientation defines the direction of the major and minor principal stress axes Sigma 1 and Sigma 3. The orientation can be specified in either Vector or Trend/Plunge format.
VECTOR
The Vector option allows you to specify the Sigma 1 and Sigma 3 directions in XYZ vector component format, where XYZ are the orthogonal axes of your RS3 model. Enter the vector components for each axis.
TREND / PLUNGE
The Trend/Plunge option allows you to specify the Sigma 1 and Sigma 3 directions in Trend/Plunge format. Trend is the azimuth direction measured from North (-360 to 360 degrees), and Plunge is the downward angle measured from horizontal (-90 to 90 degrees).
Custom Field Stress
Customized field stress may be defined for individual materials in a model, by selecting the Advanced button, and defining custom field stress as required. See the Custom Field Stress topic for details.