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Figurę 2: Estimation of constants mt/nij and s

The parameters mi/mj and i are related to changes in fracture frequency and joint condition. Hoek [1995] presented the indicative values for these parameters shown in Figurę 2 .The values of A, B and C in Table 1 were based on the values m,/m, shown in this figurę

Function I describes the changes in m,/m, with changes in the fracture frequency for VERY GOOD surface condition. The maximum and minimum values for are 0.60 and 0.17 shown in Fig. 2. These values were extrapolated to 0.69 and 0.14, considering Fig 1 has 6 degrees of fracturing and Fig. 2 shows only 4

Function 2 describes the changes in ntt/m,- with changes in the fracturing for VERY POOR surface condition. The maximum and minimum values for m,/m, are 0.08 and 0.04. The value of 0.08 was increased to 0.60 because if the number of joints is smali the joint condition become less important because there is a few or no joint in any given błock of rock mass. For this reason the ratio mi/m, must increase and become slightly lower than the ratio m^m, for massive rock with a few joints with good surface condition. The minimum value of 0.04 was kept the same.

Function 3 describes the changes that occur to the value of s with changes in the fracture frequency for VERY GOOD surface conditions. The maximum and minimum values for i are 0.19 and 0.004 as indicated in Figurę 2. The maximum value was increased to 0.25 to consider those rock masses having very few joints as shown in Figurę 1 for massive rock and very good surface conditions. The minimum value of 0.004 was kept the same.

Function 4 describes the changes in i with changes in the fracturing for VERY POOR surface condition. The maximum and minimum values for s are 0.0004 and 0.0 as indicated in Figurę 2. These values where kept without modification.