Snow shed
Encyclopedia
An avalanche snow bridge or simply snow bridge is a type of rigid snow-supporting structure
Snow-supporting structure
Snow supporting structures are structures for avalanche control. They are subdivided into rigid structures and flexible structures.Rigid structures are avalanche snow bridges, and snow racks. Flexible structures are snow nets....

 for avalanche control
Avalanche control
Avalanche control or avalanche defense activities reduce the hazard avalanches pose to human life, activity, and property. Avalanche control begins with a risk assessment conducted by surveying for potential avalanche terrain by identifying geographic features such as vegetation patterns,...

 (avalanche defense). Avalanche
Avalanche
An avalanche is a sudden rapid flow of snow down a slope, occurring when either natural triggers or human activity causes a critical escalating transition from the slow equilibrium evolution of the snow pack. Typically occurring in mountainous terrain, an avalanche can mix air and water with the...

 bridges can be made of steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

, prestressed concrete
Prestressed concrete
Prestressed concrete is a method for overcoming concrete's natural weakness in tension. It can be used to produce beams, floors or bridges with a longer span than is practical with ordinary reinforced concrete...

 frames, or timber
Timber
Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...

.

Snow bridges may superficially look similar to snow fence
Snow fence
A snow fence is a structure, similar to a sand fence, that forces drifting snow to accumulate in a desired place. They are primarily employed to minimize the amount of snowdrift on roadways and railways. Farmers and ranchers may use temporary snow fences to create large drifts in basins for a...

s, but they act differently. Snow fences are built vertically and accumulate snow on their downwind side, while snow bridges are slanted or horizontal and hold snow on their top side.

Snow bridges are fastened to the slope on the upslope side by tension anchors and on the downslope by compression anchors.

Wind shed

Railway trains occasionally get blown off the tracks by high winds.

The Lanxin High-Speed Railway
Lanxin High-Speed Railway
The Lanzhou–Urumqi High-Speed Railway, also known as Lanxin Second Railway, is a high-speed rail under construction in northwestern China. It will connect Lanzhou in Gansu Province and Ürümqi in Xinjiang Uyghur Autonomous Region....

has particularly strong winds which blow on most days of the year; a 67-kilometre long wind-protection "gallery" has been proposed to be built in this region.
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