A Study of Rock Joint Movement Under Triaxial Loading.

The test was made in order to study the movement along a sawed rock joint plane. The conclusions include the following The movement along a joint plane can be determined using the load versus axial movement curves from a sawed and from an intact rock specimen. There is no movement along the joint surface until the axial load reaches a certain value which is dependent upon the roughness of the joint surface, joint angle, rock type, and similar factors. Movement occurs then as the asperities on the joint surface are sheared off. The deviator stress versus axial strain curve indicates that the compression of the rock, before any slipping occurs on the joint plane, is essentially elastic.