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.

As a typical roof-supporting system of tunnels, Cable bolts are subjected to static and dynamic loading conditions caused by ground movements and mining activities. As mining goes deeper, the chance of undetermined ground stress concentrations increases and subsequently, the probability of sudden unexpected failures such as rock bursts increases. Many studies have been carried out to simulate the axial loading condition of the tendons, especially cable bolts, under static and dynamic loading modes; however, it barely can be seen that both behaviours have been studied and compared simultaneously. From other points of view, although research has been conducted on Barrel and Wedge and load-bearing plates, these components have hardly been considered together in axial loading studies. In this laboratory study, a new pullout testing mechanism has been introduced, which is capable of implementing axial loading of cable bolts in both static and dynamic loading conditions. In addition, in a parametric study, the role of bulbs of the cable bolts as well as barrel and wedges on the load-bearing capacity of the anchors have been examined. The bond between cable bolts and grout material in the bulbed cables behaves almost 30% stronger in static and 40% stronger in dynamic tests in comparison with plain cables. In general, the required pullout energy in dynamic tests was 25-50% less than in static tests.

With the increased use of cable bolts in mining and civil projects worldwide, it is important to understanding the performance of these support structures in different scenarios. The axial load transfer mechanisms of six cable bolts were investigated experimentally in this research study. A large-scale pull-out testing apparatus with a capacity of 1000 kN was designed and manufactured as part of the investigation. A common commercial cementitious grout with a uniaxial compressive strength of 60 MPa was used to encapsulate 300 mm length samples. Passive confinement encapsulated each sample to ensure the concrete’s integrity during the testing. The encapsulated cable bolts were then subjected to axial loads using a hydraulic ram, with the axial load and displacement measured using a load cell and LVDTs. Two scenarios were investigated: free rotation and restricted rotation. The results demonstrated that the apparatus effectively recorded the behaviour of the cable during pull-out and identified that the radial stiffness of the samples had a significant impact on the overall load of the system. The results also indicated that rotation had a limited influence on the load behaviour of the samples tested.

The ease of use and the design flexibility of cable bolts have made them a popular choice for rock support. Cable bolts can be encapsulated with cementitious grout or resin. There is a need to better understand the impact of resins on the behaviour of cable bolts under varying load and stress regimes over their long service life. This study reports on 18 large scale resin pull-out tests using a 1000 kN pull-out apparatus. The testing apparatus minimised the rotational movement of the cable at the exit point by using a fully grouted anchor tube. Six cable bolts, ranging from 50 to 100 tonnes in capacity, anchored using a fast-curing urea silica resin, were tested under monotonic and cyclic loading. Each cable type was tested twice in monotonic loading and then the average initial peak load was used to generate a cyclic loading pattern. The study found that the resin product had a relatively low load capacity regardless of the cable type, and that loading type had a minimal impact on the results. The cable diameter had a minor influence on the pull-out results. The resin provided a stiff behaviour and an excellent response to repeated loading.

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