Table 1 Statistical results of friction angle φ in rocks at all levels (°).
Basic quality level of rock mass | Ⅰ | Ⅱ | Ⅲ | Ⅳ | Ⅴ |
|---|---|---|---|---|---|
Number of sample groups | 14 | 38 | 48 | 76 | 16 |
minimum value | 54.10 | 45.02 | 42.01 | 19.81 | 17.75 |
Maximum value | 70.05 | 70.12 | 64.03 | 65.59 | 54.30 |
mean value | 63.07 | 58.35 | 54.48 | 44.56 | 35.87 |
mean square error | 5.07 | 6.00 | 5.67 | 11.24 | 10.01 |
