بررسی آزمایشگاهی اثر قوس زدگی در مصالح دانه ای به کمک دستگاه توسعه یافتۀ دریچه

نوع مقاله : پژوهشی

نویسندگان

• علی احمدی ¹
• سیداحسان سیدی حسینی نیا ²

¹ فردوسی مشهد

² دانشگاه فردوسی مشهد

10.22067/civil.v27i2.31019

چکیده

این مقاله به بررسی آزمایشگاهی اثر قوس زدگی به صورت ایجاد ساختاری به شکل قوس پایدار در مصالح دانه ای پرداخته است. بدین منظور یک دستگاه توسعه یافتۀ دریچه ساخته شده و به کمک آن ابعاد قوس ایجاد شده در مصالح دانه ای بر حسب زاویۀ اصطکاک داخلی، قطر متوسط و زاویۀ قرارگیری بستر مصالح مورد پژوهش قرار گرفته است. مشاهدات آزمایشگاهی نشان می دهند که برای همۀ مصالح مورد آزمایش با افزایش عرض دریچه و کاهش زاویۀ قرارگیری بستر مصالح دانه ای، عرض و ارتفاع قوس تشکیل شده افزایش می یابد و شکل تمامی قوس ها به صورت یک سهمی است. از طرفی به ازای یک عرض دریچه و زاویۀ بستر ثابت، با افزایش زاویۀ اصطکاک داخلی و چگالی مصالح دانه ای، ارتفاع و عرض قوس افزایش می یابد.

کلیدواژه‌ها

• قوس زدگی
• مصالح دانه ای
• دریچه
• زاویۀ بستر
• شکل قوس

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عنوان مقاله [English]

Experimental Investigation on the Arching Effect in Granular Materials by Using the Developed Trapdoor Apparatus

نویسندگان [English]

• Ali Ahmadi ¹
• Ehsan Sezedi Hosseininia ²

¹ Ferdowsi University of Mashhad

² , Ferdowsi University of Mashhad

چکیده [English]

This paper discusses the arching effect as the formation of a stable arch in granular materials. For this aim, a developed trapdoor apparatus is designed in order to investigate the arch dimensions in term of the internal friction angle, average size and base angle of materials. Observations show that for all tested granular ensembles, width and height of the arch increase with an increase in trapdoor width and a decrease in base angle. It is also found that the shape of the whole arches is governed by a parabola. In addition, for both constant values of trapdoor width and base angle, the increase in both the internal friction angle and density of granular materials leads to the increase in arch dimensions.

کلیدواژه‌ها [English]

• Arching
• Granular materials
• Trapdoor
• Base angle
• Arch width
• Arch height

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