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

Document Type : Original Article

Authors

mining engineering department, hamedan university of technology

Abstract

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.

Keywords


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