
80 Forensic Engineering Fundamentals
When seismographs are not used to monitor vibrations, a safe blasting formula
is used:
/12
(3.11)
where
D is the safe blasting distance from structure to blast hole
K is the scaling factor = 55 /lb
1/2
for structures between 301 and 5000 from the blast
W is the charge weight per delay
e scaling factor varies depending on the distance to the blast. At a distance less than
301 , the scaling factor reduces to 50 /lb
1/2
. e scaling factor corresponding to a dis-
tance greater than 5000 is 65 /lb
1/2
.
Heavy Equipment Vibrations
Heavy equipment, such as jack hammers, large trucks, and roller compactors ca ...