Grid Search
The Grid Search is one of the Search Method options in Slide3 for locating critical slip surfaces.
The Grid Search is a deterministic algorithm that involves no random steps. It requires the user to define a search grid, which is a box with x, y, z dimensions defining a grid of points representing slip centers (centers of rotation for spherical slip surfaces).
The Grid Search option only generates spherical slip surfaces. It does not work with ellipsoids or other shapes.
To enable a Grid Search:
- In the Slip Surface Options dialog, set the Surface Type = Sphere.
- Set the Search Method = Grid Search.
- Set the Grid Search Options (Number of radii per grid point).
- Select Define Search Grid from the toolbar or the Surfaces menu to define the search grid.
Grid Search Method
- The Grid Search generates spherical slip surfaces. The search grid defines the centers of rotation of the spherical slip surfaces. The number of grid points is determined when you define the search grid.
- For each grid point, "n" spheres with different radii are generated ranging from Rmin to Rmax. The number "n" is the Number of radii per point entered for the grid search options.
- Min and max radii are defined based on grid point location with respect to slope geometry (see figure below).
- The factor of safety is computed for all spheres, and the minimum safety factor is the critical slip surface determined by the Grid Search.
