Predicting the Isotropic Volumetric Compression Response of Hydrating Cemented Paste Backfill (CPB)

Deep and high-stress mining results in stress transfers onto the previously placed backfill, mines have recorded several MPa induced backfill stresses. Understanding backfill-rock mass interaction is therefore critical. Previous work considered tabular ore bodies undergoing primarily one-dimensional compression showed how reaction curves could be estimated from oedometer laboratory test results. This considers massive orebodies develops a similar approach based on isotropic curves. Isotropic tests exceeding 6 are carried out samples with 3.0 to 11.1% binder content, tested at 1-day cure time 28-day time. The curve characterized three stages: initial elastic up yield point, followed by transition stage start of final linear post-yield line $$\varepsilon_{v} - \log \left( {p^{\prime } \right)$$ space. Because these rare (the reported first for Cemented Paste Backfill), attempts made relate parameters more commonly used Unconfined Compression Strength (UCS) tests. Unifying equations as functions content found determine peak strength UCS These then related corresponding compression. Finally, slope function CPB same Then behavior reconstructed curing using values CPB. Although calibrated specific studied mine’s materials, framework general applicable other mines’ CPBs.