I need explanation regarding tieback bolt implementation and interpretation in Phase2, when analyzing deep excavations in rock.

1. What are suggested values of residual tensile capacity and bond shear stiffness of tieback? (experience and influence on the final result)

2. Is input bond strength value assumed over one 'm of bond length or over entire bond length? Default value seems non-logical...

3. Is plastic bolt model valid for determination of the safety factor value and movements of excavation and elastic bolt model for determination of axial forces in bolts induced by excavation? Results obtained in this particular case show drastic difference depending on the bolt model implementation. Axial forces in elastic bolts are overly higher than the maximum tensile capacity of strands. If restricted with plastic behavior this means that bolts have failed...

4. The graph of axial force can have its maximum close to the anchorage zone or at opposite side, i.e. close to the bonded zone. This depends on many factors, but both scenarios are valid?