A rock shed is a civil engineering structure used in mountainous areas where rock slides and land slides create highway closure problems. A rock shed is built over a roadway that is in the path of the slide. They are usually designed as a heavy reinforced concrete covering over the road, protecting the surface and vehicles from damage due to the falling rocks. Rock sheds are often associated with tunnels either augmenting the tunnel or as an economical alternative.
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Rock shed Wikipedia(Text) CC BY-SA