Abstract:
Based on the concept of mobilized angle of internal friction, the coefficient of at-rest earth pressure from limited coarse backfill
Κ0 is obtained after the analysis of the Mohr's cycle. A comparison is made with Jaky's formula for half infinite soil mass
Κ0J and active earth pressure from limited backfill
Κa. It is found that
Κ0 is close to or smaller than
Κ0J, when the internal friction angle between the rock face and backfill
δr is equal to that of backfill
Ф.
Κ0 is not only influenced by
Ф and inclination of the rock face, but also by
δr ;
Κ0 may be larger or smaller than
Κ0J, when
δr is smaller than
Ф ;
Κ0 and
Κa decrease with the increase of the inclination of the rock slop; and
Κ0 is larger than
Κa. To make the rock face rough and to adopt bench excavation are both effective methods to reduce the at-rest earth pressure from the limited backfill. A design graph is given at the end of the paper.