Field Stress Overview

The Field Stress defines the in situ stress state (magnitude and orientation of the in situ principal stresses) in the rock mass or soil, prior to excavation.

In Examine2D there are two methods of defining the Field Stress:

• Constant - in situ stress is assumed to be constant (i.e. the principal stresses do not vary with depth or location)

• Gravitational - in situ stress varies linearly with depth from a user-specified elevation or ground surface

To define the Field Stress:

1. Select the Field Stress Type (Constant or Gravitational) from the Project Settings dialog, or by clicking on the Field Stress button in the Sidebar.

2. Enter the Field Stress parameters (e.g. magnitude, orientation, elevation, unit weight) in the Sidebar.

3. Note: the required input parameters depend on Field Stress Type and also the Analysis Type - Plane Strain or Complete Plane Strain.

Constant Field Stress Input (Plane Strain)

For more information see:

• the Constant or Gravitational Field Stress topics.

• also see In Situ and Induced Stresses - Chapter 10 of Hoek's Notes on the Rocscience website.