Effect of the Size and Position of a Damping Ditch on the Reduction of the Blasting Vibration

Table 8

Comparison of calculated values and measured values of the fourth set of measuring points.

Fourth group		Measuring point #1			Measuring point #2
d	s	Test velocity	Calculated velocity	Difference	Test velocity	Calculated velocity	Difference
7.5	31.35	3.348	3.411	−0.062	2.746	2.668	0.078
11.25	31.35	2.963	2.998	−0.035	1.753	1.906	−0.153
12.75	24.15	2.605	2.658	−0.053	1.551	1.412	0.139
17.25	19.35	2.292	1.923	0.369	0.934	0.930	0.004