GENERAL33552

• Permit No: C1981010
• IBM Index Class Name: General Documents
• Doc Date: 3/11/2004
• Doc Name: Blasting Study
• From: Trapper Mining Inc.
• To: DMG
• Permit Index Doc Type: Blasting
• Media Type: D
• Archive: No

I' VIBRaTECH®
GROUND VIBRATIONS
GROUND VIBRATION CRITERIA from USBMRI-8507
The U.S. Bureau of Mines has studied various aspects of ground vibration and airblast since
1930. In 1980, the culmination of over 50 years of research was compiled into RI-85072, entitled
"Structure Response and Damage Produced by Ground Vibrations from Surface Mine Blasting".
In this study, direct measurements of structural response and damage from actual surface-mine
production blasting were observed in 76 residences for 219 production blasts. This data, along
with damage data from six additional studies, were combined with the historical data from an
eazlier report entitled Bulletin 656. Particular emphasis was placed on the frequency dependence
of structure response and it's relationship to damage.
The culmination of this study was the Appendix B curve which was entitled "Alternative
Blasting Level Criteria". The Appendix B curve used both measured structure amplification and
damage evaluations to develop criteria that involved both displacement and velocity. USBM
Report of Investigations (RI)-8507 states that residential structures are most prone to damage as a
result of vibration energy within the
10
..
V
a
`~' 1
.~
0
d
a
L
Q 0.1
frequency range of 4-12 hertz. Within
this range, a 0.5 inch per second
maximum particle velocity is
recommended to preclude 'threshold'
damage to the plaster-on-wood-lath
interior portions of older structwes.
Threshold damage is deftned by the
USBM as the loosening of paint,
small plaster cracks at joints between
construction elements or the
lengthening of old plaster cracks. A
maximum of 0.75 inch per second is
recommended for the protection of
modem drywall interior construction.
The damage threshold is normally
considerably higher for load-bearing
or other structural portions of a house.
a
0.01
10
100
Frequency (Hz)
Figure 4. U.S. Bureau of Mines Recommended
Vibration Criteria (From RI-8507)
Above 12 hertz, the allowable
vibration increases as the frequency
increases, up to 40 hertz. Above 40
hertz, a constant 2.0 inches per second
level is recommended to protect the
interior walls and ceilings of
structures, regazdless of construction
Siskind, David et al, Structural Response and Damage Produced by Ground Vibration from
Blastin¢, U. S. Bureau of Mines, RI 8507, 1980.