A Study of Blast Vibration Propagation Law under Negative Altitude Terrains

Table 3

Delay combination scheme of hole-by-hole initiation technology.

Bench height H (m)	Pitch row a (m)	Delay in the hole (ms)	Array pitch b (m)	Delay between the rows (ms)	Rock properties
6	2.5	20	2	30	The argillaceous dolomite has developed joints and cracks; the rock mass is brittle; it is primarily weathered when crushed.
7	2.8	25	2.5	40
8	3.0	25	2.5	45