Rock shed

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 equally used to protect railroads.^[1] 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 with a sloping surface to deflect slip material beyond the road,^[2] however an alternative is to include an impact-absorbing layer above the ceiling.^[3] A further use of this type of structure may be seen protecting the A4 road; although constructed primarily to alleviate risk from falling rocks from a limestone seam^[4] it also serves to protect against objects or persons falling from the Clifton Suspension Bridge^[5] where the height differential of approximately 70 metres from the bridge to the bottom of the Avon Gorge would give sufficient kinetic energy to even a relatively small item to cause injury on impact.