The landscape is not consistent as the terrain keeps on changing from one location to another. Therefore, during construction activities, efforts are made to find a site that is most suitable for the construction. Specifically, it is more favourable to avoid building roads or buildings near slopes as such an area tends to be unstable. If their soil starts to shift, it would be very problematic as it can lead to damage of structures at the bottom or destabilize those at the top. However, it may not be possible to avoid them in most situations as slopes are a common occurrence in the landscape in many areas. For such situations, slope stabilization becomes necessary.
Classification of Slope Stabilization Methods
One of the most common classifications of slope stabilization methods is the geometric technique. When these are applied, it normally leads to a different geometry of the slope. A common way of achieving this is by flattening the slope or removing a section of the soil or rock among others.
Hydrological techniques work through the interference of the groundwater table. Typically, this will be reduced for the purpose of reducing the water content of the rock or soil of the slope. A common way of doing so is by lowering water pressure in pores through surface and subsurface installation of drainage pipes. Thermal techniques that include freezing and heating can also be applied.
Chemical and Mechanical Techniques
In this slope stabilization category, external means are used to add to the shear strength of the soil or rock’s masses critical plane. Apart from this, the mechanical and chemical techniques can increase the shear strength of the slope by reducing external forces that may prompt a slope failure. The techniques usually involve the construction of structures to provide restrain and more resistance against toppling such as gabions, concrete gravity walls, cement columns and shrubs and grasses among others.
Examples of Common Slope Stabilization Methods
Water is a primary reason for the weakening of slopes. This can either be water that is running down them or groundwater found beneath them. In both cases, the water risks loosening up the slope such that it starts to slide down. This is usually addressed through the installation of drainage systems either on the surface or below. This will help to carry excess water away from the slope.
Slope failure is more likely when it is left bare. This is because the soil or rocks can easily be eroded away when there are heavy winds or rain. Vegetation can therefore be used as a simple way of slope stabilization especially on slopes that are not too steep. This will make it harder for the soil on the surface to be moved away. The roots also play a role as they help to anchor chunks of rock in place underground. Also, plants can help out with the reduction of excess groundwater by using it up.
For slopes that do not experience high levels of water, retaining walls can be a good slope stabilization method. These are constructed to literally hold the top part of the slope in position.