Rock failures are quite common, and the incidents of people being killed due to landslides keep hitting the headlines regularly. Is there any perfect plan to prevent rock failure? Can civil engineers have something to offer? Can we completely put a check to the same? Fortunately, a civil engineer can lay out ideal plans to prevent rock failures. We try to explore the seldom touched topic and present you the methods as to the governments can step in and start implementing these procedures.
According to the United States Geological Society of America, every year, at least 50 people are killed in landslides. While it mentioned that landslides could occur in all the 50 states, pacific coastal ranges such as California, Washington, Hawaii, and Oregon are prone to rockfalls.
While there are many natural and civil engineering methods for preventing rock failures, let us examine the role civil engineering plays primarily through retaining walls.
Retaining walls: Retaining walls are the supporting structures that are built specifically to support the surrounding hillock or the structure that can create a landslide due to its geographical position. They help in restraining the soil to the slope built in the terrain areas. They are basically four types of retaining walls: gravity wall, piling wall, cantilever wall, and anchored wall.
- Gravity wall: A gravity wall stands on its weight without any support. Constructed from concrete, masonry and brick, a gravity wall is usually 10 feet tall. In some cases, steel can be leveraged to reduce the thickness of the wall, which can be called as semi-gravity walls. The stone foundation, like structures that you see near the landscapes are excellent examples of gravity walls.
- Piling Wall: These structures can form part and parcel of the deep foundation. Considered to be cost-effective, piling walls are constructed by adjusting one pile after the other meticulously. Piling walls are ideal, especially where there’s a railway line and also near tunnels as it’s too dangerous if the landslide blocks the tunnel pathway that can result in a gory train mishap.
III. Cantilever wall: Working on the principles of leverage, cantilever walls are constructed with concrete. They leverage the weight of the backfill soil, and the stems of these walls are thinner compared to other types of retaining walls. Before proposing the cantilever wall, a civil engineer would assess the nature and model of the soil, kind of the wall, materials used in the construction of the wall, and subsoil water movements. So, it is pertinent to consult a civil engineer who would decide on which type of retaining wall is beneficial. Also, cantilever walls can further be of two types: – a large toe with a short heel, and a tall heel with a sharp toe. Like mentioned earlier, only an engineer would be the right person to assess what’s appropriate.
- Anchored wall: Anchored walls are built around the steel or other metals that have sharp tips at both ends. While one end pushed the wall against the terrain, the other end retains it thereby giving maximum support.
Not just governments but even individuals and business owners should pay attention to retaining walls in case the proposed construction is on the terrain.