<P> Slope stability issues can be seen with almost any walk down a ravine in an urban setting . An example is shown in Figure 3, where a river is eroding the toe of a slope, and there is a swimming pool near the top of the slope . If the toe is eroded too far, or the swimming pool begins to leak, the forces driving a slope failure will exceed those resisting failure, and a landslide will develop, possibly quite suddenly . </P> <P> If the forces available to resist movement are greater than the forces driving movement, the slope is considered stable . A factor of safety is calculated by dividing the forces resisting movement by the forces driving movement . In earthquake - prone areas, the analysis is typically run for static conditions and pseudo-static conditions, where the seismic forces from an earthquake are assumed to add static loads to the analysis . </P> <Table> <Tr> <Td> </Td> <Td> This section needs expansion . You can help by adding to it . (July 2014) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This section needs expansion . You can help by adding to it . (July 2014) </Td> </Tr>

Natural sources that can give a slope greater shear strength