Finite element modelling of fully encapsulated cable bolts in laboratory large scale pull out test

Modelling cable bolts in numerical software is a challenging task. Cables are made from multiple strands wound together and when loaded, they tend to act in a way more complex manner than rock bolts. This study used laboratory data from large scale pull out testing of fully encapsulated cable bolts using cementitious grout. A finite element method was adopted and a series of engineering simplifications and assumptions were made to increase the efficiency of the model. The results were able to illustrate a better capability in modelling the bulbed cables compared to the plain cables. Also, the sensitivity analysis proposed that increasing cable diameter for a given hole size (decreasing grout annulus thickness) can increase the overall peak load value, similar to an increase in concrete confinement, grout uniaxial compressive strength, and bulb size.