Steel Rebar. Reinforcing bar, or rebar, is a common steel bar that is hot rolled and is used widely in the construction industry, especially for concrete reinforcement.
These flows generally occur during periods of intense rainfall or rapid snow melt. They usually start on steep hillsides as shallow landslides that liquefy and accelerate to speeds that are typically about 10 miles per hour, but can exceed 35 miles per hour. The consistency of debris flows ranges from watery mud to thick, rocky mud that can carry large items such as boulders, trees, and cars.
Many natural events such as heavy rainfall, an earthquake or volcano can trigger a landslide, but human activities such as building construction can also cause or increase the chances of such an event. The biggest landslide in recorded history was triggered by the eruption of Mount St Helens in 1980, according the United States Geological Survey. Nearly 3km3 of rock moved down slope. Image: People recovering belongings after a landslide in southern Valle de Las Flores, La Paz, 27 February 2011 (credit: AFP/Getty Images)