Angle Shear Testing of 15.2 mm Seven Wire Cable Bolt

Abstract

This paper focuses on the experimental study of shear testing of 15.2 mm, 25 t capacity seven wire cables at zero, 30° and 45° angles using two different shear testing facilities at the University of Wollongong (UOW) and the University of Southern Queensland (USQ) in Toowoomba. A circular double-shear rig MK-IV was used for testing cable perpendicular to the sheared joint faces (zero angle of orientation), while testing the cable at 30° and 45° was carried out using a larger-size rectangular-shaped rig. Testing was carried out based on the double-shear testing methodology wherein cable bolts were fully encapsulated using Stratabinder HS inside of three concrete blocks representing host rocks. This study was part of the tri-universities-funded ACARP project C27040 awarded jointly to the University of New South Wales, University of Wollongong and University of Southern Queensland. The objective of the experimental testing programme was to provide the essential information for the development of numerical models that included not only the technical parameters, but also the behavioural outcomes from various tests with respect to the angles of testing and their effect on the nature of cable failure, be it pure shear, tensile shear or shear tensile, cable pretension and the credibility of the effectiveness of the Barrel and Wedge (B&W) anchorage system were evaluated. Laboratory facilities at both UOW and USQ were used in the study. The prepared double-shear samples were then positioned inside of compression testing machines and were subjected to shear testing. The values of shear load and displacement were recorded for various inclinations angles. It was found that increased angle of shear contributes to increased stiffness of the cable in shear with other parameters being equal. Subroutine codes were developed in UDEC and 3DEC to simulate shear behaviour of cable bolts installed in angles for different pretension loads. The numerical simulations indicated that UDEC and 3DEC can simulate the general shear behaviour of cable bolts reasonably well for various inclination angles and pretension values.

Strengthening Device for Improving Shear Performance of Anchor Cable in Rock Support

“…Aziz et al [ 11 , 12 ] developed and improved equipment suitable for cable-bolt shear testing and conducted in-depth research on the shear behavior of different types of anchor cables. In their most recent research, they conducted double-shear experiments on anchor cables at different anchoring angles and found that an increased angle of shear contributes to increased stiffness of the cable in shear [ 13 ]. Li et al [ 14 , 15 ] systematically investigated the shear mechanical behavior of a grouting anchor cable and its contribution to joint-plane shear strength using theoretical analysis and experimental comparison.…”

“…Many scholars have carried out more economic and effective numerical simulation analyses of the shear characteristics of cable bolts. Aziz et al [ 13 ] found that UDEC and 3DEC software achieved good numerical simulation of shear mechanical characteristics of anchor cables at different angles and prestress conditions. Mirzaghorbanali et al [ 10 ] used FLAC 2D to numerically simulate the peak load strength of prestressed grouted anchor cables, and the simulation outputs matched well with the experimental results.…”

Analysis and Design of Protection Device for Anchor Cable Pull-Out in High-Stress Roadways

“…Tang et al [27] designed and developed an energy-absorbing damping anchor bolt that consisted of the bolt body, tray, constant-resistance energy absorption device, and specially shaped bolt nut; energy absorption and support could not only effectively guide and control the release and transformation of impact energy but also consume impact energy in the cushioning process of anchor bolts, ensuring the stability of surrounding rocks and the supporting protection system. Aziz et al [28] performed shear tests on seven steel strand anchors (diameter: 15.2 mm) at angles of 0 • , 30 • , and 45 • , and believed that the stiffness of sheared anchors could be improved by increasing the shear angle. Wang et al [29] reported that anchors would experience pitting corrosion due to the long-term action of O, Cl, and S in the surrounding rock environment, reducing the outer diameter and bearing capacity of anchors and finally leading to their rupture.…”

Study on Asymmetric Support of Anchor Cable with C-Shaped Tube in Inclined Coal Seam Roadway

“…Spang et al [30] conducted shear tests on anchor bolts and found that the shear resistance of the anchor bolts is influenced by the strength of the surrounding rock. Aziz et al [31][32][33] claim that single and double shear beams are available to evaluate the anchor cable's shear ability and that the anchor cable's shear strength is correlated with its preload and installation angle.…”