مطالعه آزمایشگاهی و عددی تاثیر برنده Uشکل بر درزه های ناممتد

‌سرفرازی, وهاب; محمدی بلبان آباد, شادمان

مطالعه آزمایشگاهی و عددی تاثیر برنده Uشکل بر درزه های ناممتد

نوع مقاله : مقاله پژوهشی

نویسندگان

¹ گروه مهندسی معدن، دانشگاه صنعتی همدان

² گروه مهندسی معدن، دانشگاه صنعتی همدان.

چکیده

هدف این مقاله بررسی تاثیر فاصله داری درزه ناممتد از برنده u شکل بر مکانیزم رشد ترک می باشد. همچنین مطالعه اینکه با تغییر زاویه داری درزه ناممتد نسبت به افق و تعداد درزه ناممتد، مکانیزم رشد ترک چگونه تغییر می کند. به این منظور 9 نمونه های با ابعاد cm 10* cm 10* cm 5 حاوی درزه ناممتد ساخته شد. سه نمونه اول دارای یک درزه ناممتد با زاویه داری های 0 ،45 و90 درجه، طول 2 سانتی متر و فاصله درزه تا برنده u شکل 2 سانتی متر می باشد. سه نمونه دوم دارای یک درزه ناممتد با زاویه داری های 0 ،45 و90 درجه، طول 2 سانتی متر و فاصله درزه تا برنده u شکل 4 سانتی متر میباشد. سه نمونه سوم دارای دو درزه ناممتد با زاویه داری های 0 ،45 و90 درجه که طول درزه های ناممتد 2 سانتی متر و فاصله درزه ناممتد اول تا برنده u شکل 2 سانتی متر و فاصله درزه ناممتد دوم از درزه ناممتد اول 2 سانتی متر میباشد. نمونه ها با نرخ mm/s 01/0 تحت آزمایش قرار گرفتند. همزمان با انجام مطالعات آزمایشگاهی، شبیه سازی عددی توسط نرم افزار FRANC2D نیز بر روی نمونه های حاوی درزه های ناممتد انجام شد. نتایج نشان می دهند که فاصله داری درزه ناممتد اتا برنده u شکل، زاویه داری درزه ناممتد و تعداد درزه ناممتد تاثیر بسزایی برمکانیزم رشد ترک دارد. همچنین نتایج نشان دادند که مود شکست و الگوی شکست نمونه های آزمایشگاهی و مدل های عددی مشابه می باشند.

کلیدواژه‌ها

عنوان مقاله [English]

Experimental and numerical investigation on the effect of u shape cutter force on the non-persistent joint

نویسندگان [English]

vahab sarfarazi ¹
shadman mohamadi bolban abad ²

¹ mining engineering department, hamedan university of technology

² mining engineering department, hamedan university of technology

چکیده [English]

The aim of this paper is to study the effect of spacing of the joint from ‘u’ shape cutter on the fracture mechanism and to investigate the effect of joint angularity under ‘u’ shape cutter loading on the shear failure mechanism. For this purpose nine sample with dimension of 5 cm *10 cm*10cm consisting non-persistent joints were prepared. The first sets of three specimens have one non-persistent joint with length of 2cm and angularity of 0, 45 and 90. The spacing between joint and top of the sample was 2cm. The second sets of three specimens have one non-persistent joint with length of 2cm and angularity of 0, 45 and 90. The spacing between joint and top of the sample was 4cm. The third sets of three specimens have two non-persistent joint with length of 2cm and angularity of 0, 45 and 90. The spacing between upper joint and top of the sample was 2cm and the spacing between lower joint and upper joint was 2cm. the samples were tested under loading rate of 0.01 mm/s. concurrent with experimental investigation, numerical simulation were performed on the non-persistent joint using FRANC2D. the results shows that the spacing between joint and specimen edge and joint angularity have important effect on the crack growth mechanism. Also, failure mode and failure pattern in experimental test and numerical simulation are similar.

کلیدواژه‌ها [English]

U shape cutter
non-persistent joint angle
joint number
joint spacing

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