How does rock reinforcement function?

For rocks with widespread fractures, individual blocks resulting from these fractures may fall out and as a result slope failure may occur. Rock reinforcement (e.g. rock dowels, bolts or anchors) is installed to bolt through the discontinuities in rock to enhance the rock to behave as a single unit. With the bolting across block interfaces, the stresses would be altered within the rock mass. For untensioned rock dowels, they may be subjected to tensile forces arising from rock movement. Other than the provision of rock reinforcement, shotcreting is another method to reinforce the rock. It functions by griping the rock together and maintaining the small blocks which hold the large blocks in position.

This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.