Water Pressure Grid Overview
A Water Pressure Grid allows you to model the Groundwater Pore Pressure or Joint Water Pressure distribution by defining the Total Head, Pressure Head or Pore Pressure at a grid of discrete XYZ locations. From the data at the grid points, the Pressure at any point in a material can be determined using the specified interpolation method.
The grid data could be based on field measurements or could be the output from a seepage analysis program.
One grid or multiple grids can be defined. Only one grid can be assigned for a given material or joint property. Water Pressure Grids are created and assigned as summarized below.
Adding Water Grids
Water Grids are created with the Add Water Pressure Grid option.
Assigning Water Grids
In order for a Water Grid to be used in the RocTunnel3 analysis, it must be either assigned to a Material or to a Joint Property.
Assigning Water Grids to Materials
Water Grids are assigned to Materials under the Water Parameters tab of the Define Materials dialog or with the Hydraulic Assignments Dialog. See the Assign Water to Materials topic for more details. In order for Material pore pressures to be used in Joint Water Pressure calculations:
- The Water Pressure Method must be set to Material Dependent for the Joint Property
- The Joint with the Joint Property must pass through the Material with the assigned Water Grid
Assigning Water Grids to Joint Properties
Water Grids are assigned to Joint Properties under the Water Parameters tab of the Define Joint Properties dialog. See the Define Joint Properties topic for more details.
Types of Water Grids
There are three different types of Water Grid:
- Pore Pressure
- Pressure Head
- Total Head
The Water Grid Type is selected when you create a Water Grid with the Add Water Pressure Grid option. For details about the properties of each Water Grid Type see the above links.