Water Pressure Grid Overview

A Water Pressure Grid allows you to model the groundwater pore 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 pore 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.

• Water Pressure Grids in Slide3 are only used for pore pressure calculations. If you need to model ponded water then you must use Water Surfaces.

One grid or multiple grids can be defined. Only one grid can be assigned for a given material. 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

Water Grids are assigned to materials under the Water Parameters tab of the Material Properties dialog, or with the Hydraulic Assignments dialog.

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.