کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
275062 507524 2016 4 صفحه PDF ندارد دانلود رایگان
عنوان انگلیسی مقاله
Vertical load capacities of roof truss cross members
ترجمه فارسی عنوان
ظرفیت بار عمودی اعضای صلیب سقف خرپا
کلمات کلیدی
سقف از فلز؛ استخراج از معادن زغال سنگ؛ کنترل زمینی؛ ظرفیت بار؛ پشتیبانی سقف
Roof truss; Coal mining; Ground control; Load capacity; Roof support
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی اقتصادی
چکیده انگلیسی

Trusses used for roof support in coal mines are constructed of two grouted bolts installed at opposing forty-five degree angles into the roof and a cross member that ties the angled bolts together. The load on the cross member is vertical, which is transverse to the longitudinal axis, and therefore the cross member is loaded in the weakest direction. Laboratory tests were conducted to determine the vertical load capacity and deflection of three different types of cross members. Single-point load tests, with the load applied in the center of the specimen and double-point load tests, with a span of 2.4 m, were conducted. For the single-point load configuration, the yield of the 25 mm solid bar cross member was nominally 98 kN of vertical load, achieved at 42 cm of deflection. For cable cross members, yield was not achieved even after 45 cm of deflection. Peak vertical loads were about 89 kN for 17 mm cables and 67 kN for the 15 mm cables. For the double-point load configurations, the 25 mm solid bar cross members yielded at 150 kN of vertical load and 25 cm of deflection. At 25 cm of deflection individual cable strands started breaking at 133 and 111 kN of vertical load for the 17 and 15 mm cable cross members respectively.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Mining Science and Technology - Volume 26, Issue 3, May 2016, Pages 517–520
نویسندگان
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