We can easily see 'unrestrained slopes' around us. Unrestrained slope means an exposed ground surface that stands at an angle with the horizontal. This slope can be natural or made artificially. When we construct roads, buildings, or any other infrastructure, we face these slopes and they sometimes need to be cut and stabilized so that they do not fail. In order to check the safety we have to consider the shear stress developed along the slope surface and the shear strength of the soil. There are few methods to analyze slope stability. For this project we mainly use ordinary method of slices to figure out the safety of the given slope. To get the factor of safety by this method, it is first to suppose that an arc of a circle represents the failure surface( in the picture below). Then divide the soil above the arc into several slices. The more slices we have, the more accurate result we get. The width of slices does not have to be same. Next step is to calculate the weight of each slice by multiplying the area and unit weight of soil.
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