The Focus Tangent option allows you to generate slip circles which are TANGENT to a line segment. To create a Focus Tangent:
Select Add Tangent Line from the Focus Search sub-menu in the Surfaces menu.
You will be prompted to enter two points defining the tangent line. Enter the points graphically with the mouse, or enter x,y coordinates in the prompt line.
After the second point is entered, the tangent line will be added to the model, and you will automatically exit from the Focus Tangent option.
An example of a Focus Tangent, and the resulting analysis, showing all generated slip circles, is illustrated in the figure below.
Tangent line focus used with Grid Search
NOTE:
For each grid slip center, only ONE circle, tangent to the line, can be generated. The Radius Increment is therefore NOT APPLICABLE when using the Focus Tangent option.
The line segment which is defined with the Focus Tangent option, is automatically extended (during the analysis) to form an infinite line. Therefore it does not actually matter where the endpoints of the tangent line are located. All slip circles which are generated, will be tangential to the infinite line which contains the line segment you have drawn.