**4. Hydraulic fracturing test with normal flow rate in same test section of good rock mass**

It is necessary to find out or validate the results obtained by using high flow rate technique to measure the maximum principal horizontal stress and its direction in highly fractured rock mass. Hence two to three zones of good rock mass area where the rock mass is not highly fractured were identified in the same borehole and conducted the experiments with normal flow rate method of 4–6 l/min to create the new fracture for classical hypothesis or to reopen the existing fractures. Tests with normal flow rate in non-fractured rock mass would give nearer result to correlate with the high flow rate technique. Other methods may show some difference

All the experiments were conducted in the EX-size hole at the depth where the rock mass was not fractured. These particular zones were selected after careful observation of core logging data. The injection unit was placed at this depth for the pressurization. The pressure was injected at a rate of 6 l/min for a span of 50–250 sec and the pressure was instantaneously increased up to 90–100 bars. The shut-in pressure could be achieved even though the pump was shut-off at certain peak levels [25]. It clearly indicated that normal stress required for reopening of the pressure could build up across the fracture [21]. The detailed procedure of the experiments, results obtained at different places are given below (**Tables 5**–**8**).
