CIVIL ENGINEERING FORMULAS

SOIL AND EARTHWORK FORMULAS 205

The acceleration a, in/s^2 , of the particles is given by

(8.72)

For a charge exploded on the ground surface, the overpressure P, psi, may be
computed from

(8.73)

whereWmaximum weight of explosives, lb per delay
Ddistance, ft, from explosion to exposure

The sound pressure level, decibels, may be computed from

(8.74)

For vibration control, blasting should be controlled with the scaled-distance
formula:

(8.75)

whereconstant (varies for each site)
Hconstant (varies for each site)

Distance to exposure, ft, divided by the square root of maximum pounds per
delay is known as scaled distance.

vH

D

W

β

dB

P

6.95 10 ^28 

0.084

P226.62

W^1 ^3

D 

1.407

a 4

2 f^2 A