کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6426965 1634465 2014 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Retarding avalanches in motion with net structures
ترجمه فارسی عنوان
عقب انداختن لاک ها در حال حرکت با ساختارهای خالص
کلمات کلیدی
خالص برف، بهمن اندازه گیری حفاظت، آزمایش گرانولا، اندازه مش، طول مسیر
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
چکیده انگلیسی


- Force measurement exerted by an avalanche to a steel wire rope structure
- Granular experiments on scaled net barriers
- Analyzing the influence of the mesh size to granular flows

Steel wire rope nets have become a common protection measure against snow avalanches in Europe, as they can prevent a release in potential starting zones. A novel approach in this context, is to retard the movement of an avalanche after it has been initiated. A full scale structure, the so-called Snowcatcher, was installed and instrumented with several load measuring pins, which record the dynamic loads caused by an avalanche. The motivation of the measurements is to observe the influence of net structures on snow avalanches. In the lab, scaled granular experiments were performed in two set-ups, investigating the influence of i) the net barrier angle and ii) the mesh size of the net. For both set ups various experiments with different chute inclinations were performed. The results from measuring the front velocities and flow depths showed that higher chute angles are accompanied with both, higher flow velocities and Froude numbers. Experiments with different net barrier angles showed that the effectivity increases with higher chute inclinations. Furthermore the results indicate that different barrier angles slightly influence the effectivity, e.g. for small chute inclinations, nets perpendicular to the flow direction lead to lower effectivities than inclined nets. Experiments with different mesh sizes indicate a velocity dependency of the effectivity corresponding to a certain ratio of mesh to grain size. Smaller mesh sizes in the range of the maximal particle grain size lead to an obstruction of the net, acting as a solid barrier and therefore reaching best effectivity, notwithstanding overflows. For large mesh sizes the effectivity of the net barrier increases with a higher velocity of the flow.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cold Regions Science and Technology - Volume 97, January 2014, Pages 159-169
نویسندگان
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