RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting

Jun 29, 2005

D. Siskind, M. Stagg, J. Kopp & C. Dowding

RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 
 
    
 Report of Investigations 8507
 
 Structure Response and Damage
Produced by Ground Vibration
From Surface Mine Blasting
 
 By D. E. Siskind, M. S. Stagg, J. W. Kopp,
and C. H. Dowding
 
 UNITED  STATES DEPARTMENT OF THE INTERIOR
Cecil D. Andrus, Secretary
 
 BUREAU OF MINES
 
 Lindsay D. Norman, Director
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 1 of 84 
  
 
   
 This publication has been cataloged as follows:
 
 United States. Bureau of Mines
Structure response and damage produced by ground vibration
 
 from surface mine blasting.
 
 (Report of investigations - Bureau of Mines ; 8507)
 
 Bibliography: pU  69-70,
 
 1 . Blast effect. 2.  Buildings-Vibration, 3.  Soils-Vibration,
4.  Strip mining-Environmental aspects.  I .  Siskind, D, E. II .  Title.
III. Series: United States. Bureau of Mines. Report of investigations ;
8507.
 
 TN23 .U43 CTA654.71 622s C690’.211 80-607825
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 2 of 84 
  
 
   
 CONTENTS
 
 Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Introduction- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Ground vibration characteristics . . . . . . . . . . . . . . . . 5
 
 Time and frequency properties of mining blasts 5
Other vibration sources . . . . . . . . . . . . . . . . . . . . . 6
 
 Generation and propagation . . . . . . . . . . . . . . . . . . . 9
Blast design and ground vibration generation . . . 9
Vibration comparisons: Mine and quarry blasts . 1 4
 
 Response of residential structures . . . . . . . . . . . . . . . 1 8
Response spectrum analysis techniques . . . . . . . . . 1 8
Direct measurement of structure responses . . . . . 2 1
 
 Test structures . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1
Instrumenting for response . . . . . . . . . . . . . . . . 30
Natural frequency and damping . . . . . . . . . . . . 30
Production blasting . . . . . . . . . . . . . . . . . . . . . . . 3 1
Velocity exposure levels . . . . . . . . . . . . . . . . . . . 51 .
Structure responses from blasting . . . . . . . . . . . . 32
Amplification factors . . . . . . . . . . . . . . . . . . . . . . 33
Airblast  response . . . . . . . . . . . . . . . . . . . . . . . . . 4 1
Structure responses from everyday activities . . . 41
 
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 Failure characteristics of building materials . . . . . . .
Gypsum wallboard failure . . . . . . . . . . . . . . . . . . .
Masonry and concrete failure . . . . . . . . . . . . . . . . .
Fatigue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 Safe vibration levels for residential structures . . . . .
Previous damage studies . . . . . . . . . . . . . . . . . : , . .
New Bureau of Mines damage studies . . . . . . . . .
Summary damage analysis . . . . . . . . . . . . . . . . . . .
 
 Mean and variance analysis . . . . . . . . . . . . . . . . .
Probability analysis . . . . . . . . . . . . . . . . . . . . . . .
 
 Safe blasting levels . . . . . . . . . . . . . . . . . . . . . . . . .
Response spectra analysis of damage cases . . . . . .
 
 Existing standards for vibrations . . . . . . . . . . . . . . . .
Human response . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix A.-Existing vibration standards and cri-
 
 teria to prevent damage . . . . . . . . . . . . . . . . . . . . .
Appendix B.-Alternative blasting.level  criteria . . . .
 
 ILLUSTRATIONS
 
 Occupied residences near operaiing surface mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Predominant frequencies of vibrations from coal mine, quarry, and construction blasting . . . . . . . . .
Coal mine blast time histories and spectra measured at 2,287 ft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Quarry blast time histories and spectra measured at 540 ft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Construction blast time histories and spectra measured at 75 ft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ground vibrations from a single coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radial ground vibration propagations from surface coal mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vertical ground vibration propagations from surface coal mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transverse ground vibration propagations from surface coal mines . . . . . . . . . . . . . . . . . . . . . . . . . .
Summary of ground vibrations from all surface coal mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Zones of mean propagation regressions for two major  types of blasting . . . . . . . . . . . . . . . . . . . . . . .
Ground vibration propagation for three types of blasting as found by Lucole . . . . . . . . . . . . . . . . . .
Single degree of freedom model and types of structures response . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Response spectra for mining and construction shots, after Corser . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 19, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 20, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,. .
Test structure 2 1, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 22, near a quarry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 23, near a quarry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 26, near a coal mme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 27, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 28, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 29, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 30, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 3 1, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 49, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 51, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test structure 61, near a coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vibration gages mounted in corners and on walls for measuring structure response in structure 51
Ground vibration, structure vibration, and airblast  time histories from a coal mine highwall  blast .
Residential structure natural frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Residential structure damping values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Corner and midwall  responses for a single structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Structure responses (corners) from peak horizontal ground vibrations, summary . . . . . . . . . . . . . . . .
Structure responses (corners) from peak horizontal ground vibrations with measured,values . . . . . .
Structure responses (corners) from peak vertical ground vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
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 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 3 of 84 
  
 
   
 ILLUSTRATIONS-Continued
 
 37.
38.
 
 39.
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41.
 
 42.
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 51.
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6 7 :
 
 Midwall  responses from peak horizontal ground vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Amplification factors for blast-produced structure vibration (corners) of a single l-story and a smgle P-story
 
 house . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Amplification factors for blast-produced structure vibration (corners), all homes . . . . . . . . . . . . . . . . . . . . . . . .
Amplification factors for blast-produced midwall  vibration, all homes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ground vibration and airblast  that produce equivalent amounts of structure response, in frame residential
 
 structures of up to 2 stories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test residential fatigue structure near surface coal mine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plan of main floor of test fatigue structure shown in figure 42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Failire  strains for residential construction materials from a variety of sources (tables 7 and 8) . . . . . . . . . . . . .
Fatigue test model on biaxial vibrating table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .:
Damage observations, new Bureau of Mines data from production blasting in surface mmes...............................
Nondamage observations, new Bureau of Mines data from surface mine blasting . . . . . . . . . . . .
Displacement versus frequency for low-frequency blasts in glacial till, set 2 mean and variance analysis..................
Displacement versus frequency for low-frequency blasts and shaker tests, set 4 mean and tiriance  analysis ,
Displacement versus frequency for low-frequency blasts, shaker tests, and masonry damage, set 5 mean and
 
 varianceanalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement .versus  frequency for high-frequency blasts, set 6 mean and variance analysis . . . . . . . . . . . . . . .
Displacement versus frequency summary, set 7 mean and variance analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Velocity versus frequency for the various damage data sets, mean and variance analysis . . . . . . . . . . . . . . . . . .
Velocity versus frequency summary, set 7 mean and variance analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Probability damage analysis for low-frequency blasts in glacial till, set 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Probability damage analysis for low-frequency blasts and shaker tests, set 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Probability damage analysis for low-frequency blasts, shaker tests, and masonry damage, set 5 . . . . . . . . . . . . .
Probability damage analysis for high-frequency blasts, set 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Probability damage analysis summary, set 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
kuman tolerance standards for rms vibrations exceeding l-minute-duration IS0 263 1 . . . . . . . . . . . . . . . . . . .
Human response to steady-state and transient vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Human response to transient vibration velocities of various durations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Human response to transient vibration accelerations of various durations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Human response to vibrations of damped concrete floors, after Murray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Human response to concrete floor vibrations of various durations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Human response to vibrations of various durations, summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reactions of persons subjected to blasting vibration in their homes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .
 
 B-l. Safe levels of blasting vibration for houses using a combination of-  velocity and displacement . . . . . . . . . . , . . ,
 
 TABLES
 
 ::
Production blasts and ground vibration measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equations and statistics for ground vibration propagation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 3 . Test structures and measured dynamic properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 . Equations and statistics for peak  structure responses from ground vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 ii*
Strains in fatigue test structure from blasting and human activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 7 :
Structure vibrations in test fatigue structure from blasting and human activity . . . . . . . . . . . . . . . . . . . . . . . . . .
Failure characteristics of plaster and gypsum wallboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 8 . Failure of masonry and concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9 . Studies of damage to residences from blasting vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 10. Damage classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11. Data sets used for damage analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12. Summary of damage statistics by data sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13. Safe levels of blasting for residential type structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14. Studies of human response to vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15. Subjective responses of humans to vibrations of various durations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-l. German vibration standards, DIN 4150 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-2. Damage levels from blasting, after Langefors and kihlstrom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-3. Limiting safe vibration values of pseudo vector sum peak particle velocities, after Esteves . . . . . . . . . . . . . . . . .
A-4, Limiting safe vibration values, after Ashley . . . . . . . . . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
 Pap
 
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67
71
71
 
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A-5. Vibratidn limits for laboratory instruments, after Whiffin and Leonard . . . . . . . . . . . . . . . . , . . , . . . , . , , . . . . 72
 
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 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 4 of 84 
  
 
   
 STRUCTURERESPONSEANDDAMAGE
PRODUCEDBYGROUNDVIBRATIONFROM
 
 SURFACEMINEBLASTING
bY
 
 D. E. Siskind’,  M.S. Stagg2,  J.  W. Kopps,  and C. H. Dowding
 
 ABSTRACT
 
 The Bureau of Mines studied blast-produced ground vibration from surface
mining to assess its damage and annoyance potential, and to determine safe
levels and appropriate measurement techniques. Direct measurements were
made of ground-vibration-produced structure responses and damage in 76
homes for 219 production blasts. These results were combined with damage
data from nine other blasting studies, including the three analyzed previously
for Bureau of Mines Bulletin 656.
 
 Save levels of ground vibration from blasting range from 0.5 to 2.0 in/set
peak particle velocity for residential-type structures. The damage threshold
values are functions of the frequencies of the vibration transmitted into the
residences and the types of construction. Particularly serious are the low-fre-
quency vibrations that exist in soft foundation materials and/or result from long
blast-to-residence distances. These vibrations produce not only structure reso-
nances (4 to 12 Hz for whole structures and IO to 25 Hz for midwalls) but also
excessive levels of displacement and strain.
 
 Threshold damage was defined as the occurrence of cosmetic damage; that
is, the most superficial interior cracking of the type that develops in all homes
independent of blasting. Homes with plastered interior walls are more suscep-
tible to blast-produced cracking then mqdern  gypsum wallboard; the latter are
adequately protected by a minimum particle velocity of approximately 0.75 in/
set for frequencies below 40 Hz.
 
 Structure response amplification factors were measured; typical values were
1.5 for structures as a whole (racking) and 4 for midwalls, at their respective
resonance frequencies. For blast vibrations above 40 Hz, all amplification factors
for frame residential structures were less than unity.
 
 The human response and annoyance problem from ground vibration is ag-
gravated by wall rattling, secondary noises, and the presence of airblast. Ap-
proximately 5 to 10 pet  of the neighbors will judge peak particle velocity levels
of 0.5 to 0.75 in/set  as “less than acceptable” (i.e., unacceptable) based on direct
reactions to the vibration. Even lower levels cause psychological response prob-
lems, and thus social, economic, and public relations factors become critical for
continued blasting.
 
 1 Geophysicist, Twin Cities Research Center. Bureau of Mines, Twin Cities, Minn.
*Civil  engineer. Twin  Cities Research Center. Bureau of Mines, Twin Cities, Minn.
3  Mining engineer, Twin Cities Research Center. Bureau of Mines, Twin Cities, Minn.
‘t Civil engineer; Professor of Civil Engineering. Northwestern University. Evanston, 111.
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 5 of 84 
  
 
   
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 6 of 84 
  
 
   
 INTRODUCTION
 
 Gound vibrations from blasting have been a continual problem for the mining
industry, the public living near the mining operations, and the regulatory agen-
cies responsible for setting environmental standards. Since 1930, the Bureau of
Mines has studied various aspects of ground vibration, airblast, and instrumen-
tation, culminating in Bulletin 656 in 197 1(37)5.
 
 In that publication, Nicholls extensively reviewed blast design effects on the
generation of vibrations, ground vibration and airblast  propagation, and seismic
instrumentation. Bulletin 656 established the use of peak particle velocity in
place of displacement, a minimum delay interval of 9 msec  for scaled distance
calculations, and a safe scaled distance design parameter of 50 ft/lbJc?  for quarry
blasting in the absence of vibration monitoring. The authors also included a
damage summary analysis originally published in 1962 by Duvall and Fogelson
as Bureau of Mines Report of Investigations 5968 (14). New data available since
the 1962 report were described in Bulletin 656, but a new analysis to include
these data was not performed.
 
 Recommended was the use of peak particle velocity to assess the damage
potential of the ground vibrations, and 2.0 in/set  as an overall safe level for
residential structures. These recommendations have been widely adopted by
the mining and construction industry and incorporated into numerous State
and local ordinances that regulate blasting activity. Soon after publication of the
2.0-in/set  safe level criterion, it became apparent that it was not practical to blast
at this high vibration level. Many mining operations with nearby neighbors were
designing their blasts to keep velocities as low as 0.40 in/set.  Severe house rattling
caused fear of property damage below the 2.0-in/set  level, and many home-
owners were attributing all cracks to the blast vibrations.
 
 Pennsylvania was the first State to adopt the P.O-inlsec  peak particle velocity
criterion as a safe standard in 1957. However, in 1974 it was forced to adopt
stricter controls because of citizen pressure and lawsuits involving both annoy-
ance and alleged damage to residences. There existed no technologically based
and supportable criteria for mine, quarry, and construction blasting other than
the 2.0~inlsec  criteria from Bulletin 656 and RI 5968. The general growth of
mining, the proximity of mining and quarrying to their residential neighbors,
and greater environmental awareness have all required reexamination of blast-
ing regulations and justified further research.
 
 In 1974 the Bureau of Mines began to reanalyze the blast damage problem,
expand the Duvall and Fogelson 1962 study, and overcome its more serious
shortcomings through the following efforts:
 
 1. Direct measurements were made of structural response, and damage was
observed in residences from actual surface-mine production blasting.
 
 2. Damage data from six additional studies, not available in 1962, were com-
bined with three studies analyzed by Duvall and Fogelson, plus the new Bureau
of Mines measurements.
 
 3. Probabilistic analysis techniques were used on various sets of data, as well
as the.conventional  statistical derivation of mean square fit and standard de-
viation for the various damage thresholds.
 
 4. Particular emphasis was placed on the frequency dependence of structure
response and damage, recognizing that the response characteristics and fre-
quency content of the vibrations are critical to response levels and damage
probabilities.
 
 5. An analysis was made of various studies of human tolerance to vibrations,
although most data are from steady-state rather than impulsive sources.
 
 5  Underlined numbers  in parentheses refer to items in the list of references
preceding the appendixes.
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 7 of 84 
  
 
   
 An understanding of how houses respond to ground vibration and the vi-
bration characteristics most closely related to this response will enable operators
to design blasts to minimize adverse effects. The mining industry needs realistic
design levels and also practical techniques to attain these levels. At the same
time, environmental control agencies responsible for blasting and explosives
need reasonable, appropriate, and technologically established and supportable
criteria on which to base their regulations. Finally, neighbors around the mining
operations and other blasting, as shown in figure 1, require protection of their
property and health so that they do not bear an unreasonable ,personal cost.
 
 This report summarizes the state of knowledge on damage to residences from
surface mine, quarry, and construction blasting. Included are discussions of
applicable data on fatigue and human response, although work is continuing
in these areas. An analysis was also made on vibration production from mining
blasts. The generation and propagation data in Bulletin ‘656 are for smaller
quarry blasts, which are also typically characterized by thin overburden layers.
 
 The damage criteria presented herein were developed to quantify the re-
sponse of and damage to residential-type structures from small to intermediate-
sized blasts as used in mining, quarrying, construction, and excavation. Appli-
cation of these criteria by regulatory agencies will require an analysis of social
and economic costs and benefits for the coexistence of blasting and an enviro-
mentally conscious society.
 
 ACKNOWLEDGMENTS
 
 The authors acknowledge the generous assistance of many regulatory agen-
cies, engineering consultants, powder companies, homeowners, and mine and
quarry operators. Special thanks are due to the Pennsylvania Department of
Environmental Resources for demonstrating the need for this ground vibration
research. Much of the fieldwork and data reduction was done by Virgil J. Sta-
chura,  Alvin J. Engler, Steven J. Sampson, Michael P. Sethna, Bryan W. Huber,
Eric Percher,  and John P. Podolinski. Valuable technical support was provided
by G. Robert Vandenbos for all stages of the blasting research.
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 8 of 84 
  
 
   
 GROUND VIBRATION CHARACTERISTICS
 
 Ground vibrations from blasting are an un-
desirable side product of the use of explosives
to fragment rock for mining, quarrying, exca-
vation, and construction. This ground vibration
or seismic energy is usually described as a time-
varying displacement, velocity, or acceleration
of a particular point (particle) in the ground. It
can also be measured as various integrated (av-
eraged) energy levels. Three mutually orthog-
onal time-synchronized components are re-
quired to characterize the motion fully.
Alternatively, the three components can be com-
bined into a true vector sum for any instant in
time or a pseudo vector sum derived from vector
addition of the maximums of each component,
independent of time (50).
 
 The descriptors for motion are related by in-
tegration and differentiation:
 
 V = &D = $ Adt.
 
 and A = $ V = fD
 
 where D is displacement, V is velocity, and A is
acceleration. When the vibrations can be ap-
proximated by a sine wave (simple harmonic
motion), the relationships above become:
 
 D  =  Do  sin(2?rft),
V  =D, (2rft)cos(2aft)  =  V,cos(2?rft),
 
 and A = - D,(2nft)%in  (2.rrft)
= - A,sin(2+rrft).
 
 where f is frequency, t is time, and, D,, VO,  and
A, are constants. Peak values correspond to the
time when the trigonometric functions equal
unity, and the relationships for these peaks val-
ues then become:
 
 D, =
VA= A,
 
 2nf EZF
 
 v,= 2tifD,  = ef
 
 and A, = (21rf)‘D, = ,27rfV,,
 
 Complex vibrations cannot be approximated by
the simple harmonic motion, and either elec-
tronic or numeric (computer) integration and
 
 differentiation become necessary for conver-
sions.
 
 Interactions between the vibrations and the
propagating media give rise to several types of
waves, including direct compressional and shear
body waves, refracted body waves, and both hor-
izontally and vertically polarized surface waves.
These vibrational waves are of primary impor-
tance in studies of the earth’s interior and earth-
quake characteristics, but their individuai effects
have been totally neglected in blasting seismol-
ogy. Analysis of damage to structures does not
require knowledge of what happens between the
source and the receiver or of the type of wave--.--
It requires only the vibrational input to the
house at its foundation. Additionally, multiply-
delayed shots are sufficiently complex vibration
sources to make identification of individual
waves difficult, if not impossible, under most
conditions.
 
 TIME AND FREQUENCY PROPERTIES
OF MINING BLASTS
 
 The amplitude, frequencies, and durations of
the ground vibrations change as they propagate,
because of (a) interactions with various geologic
media and structural interfaces, (b) spreading
out the wave-train through dispersion, and/or
(c) absorption, which is greater for the higher
frequencies. Close to the blast the vibration char-
acter is affected by factors of blast design and
mine geometry, particularly charge weight per
delay, delay interval, and to some extent direc-
tion of initiation, burden, and spacing (56). At
large distances the factors of blast design be-
come less critical and the transmitting medium
of rock and soil overburden dominate the wave
characteristics.
 
 Particle velocity amplitudes are approxi-
mately maintained as the seismic energy travels
from one material into another (i.e., rock to soil),
probably from conservation of energy. How-
ever, the vibration frequency and consequently
the displacement and acceleration amplitudes
depend strongly on the propagating media.
Thick soil overburden as well as long absolute
(as opposed to scaled) distances create long-du-
ration, low-frequency wave trains. This in-
creases the response and damage potential of
nearby structures.
 
 Copyright © 2005 International Society of Explosives Engineers
 RI 8507 Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting 9 of 84 
  
 
   
 Frequencies below 10 Hz produce large ground
displacement and high levels of strain, and also
couple very efficiently into structures where typ-
ical resonant frequencies are 4 to 12 Hz for the
corner or racking motions. Racking is whole-
structure distortion with characteristic shear
stresses and failures. Previous studies described
the frequency character of vibration from quarry
(37) and coal mine blasts (56),  and a recent re-
port by Stagg on instrumentation for ground
vibration summarized the frequency character-
istics of vibrations from small to moderate-sized
blast sources (50).  Ground vibration frequencies
from three types of blasts are shown in figure
2, all measured at the closest residence where
peak particle velocities were within 0.5 to 2.0 in/
sec. Although the shot types in figure 2 are la-
beled coal mine, quarry, and construction, the
frequency-determining factors are the shot sizes,
distances, and rock competence. The coal mine
and quarry blasts were all more than 200 lb/de-
 
 .3 -
Coal mine blasting
 
 .2
 
 .I
 
 Conatructton  blasting
 
 1
 
 0 IO 20 3 0 4 0 5 0 60 70 9 0 9 0 1 0 0 110 1 2 0
FREOUENCY.  Hz
 
 Figure Z.-Predominant frequencies of
vibrations from coal mine, quarry, and
 
 construction blasting.
 
 lay at distances exceeding 350 ft. The construc-
tion (and excavatiosl)  shots ranged from 1 r/4  to
12% lb at distances of 30 to 160 ft. Soil over-
burdens were 0 to 5 ft for construction, under
10 ft for quarries, and generally above 5 to 10
ft for coal mines.
 
 Time histories and Fourier frequency ampli-
tude spectra from three typical blasts measured
by a buried three-component transducer are
shown in figures 3 to 5 (50). The coal mine shot
is characterized by a trailing  large-amplitude,
low-frequency wave, which is probably a surface
wave generated in the overburden layers. Quarry
blasts do not usually show this low-frequency tail
for one or more of the following reasons:
smaller charge weights, smaller shot to instru-
ment distances, and thinner soil overburdens.
The combination of large shots, thick soil and
sedimentary rock overburdens, relatively good
confinement, and long-range propagation make
coal mine blast vibrations potentially more se-
rious than quarry and construction blasts be-
cause of their low frequencies. By contrast, coal
mine highwall blasts are inefficient generators
of airblast  (46). Hard rock construction and ex-
cavation blasts tend to be shorter in duration
and contain higher frequency motions than
those of either coal mine or quarry.
 
 Frequency characteristics of blast vibrations
depend strongly on the geology and blast delay
intervals. Except for the short-distance, all-rock
case, they are difficult to predict and vary
widely. Therefore, it is desirable to obtain com-
plete time histories rather than simple peak val-
ues in any sensitive areas. Many examples of
continual complaints about severe rattling at lev-
els below 0.5 in/set  are attributable to the low
frequencies. Research is continuing on the ef-
fects 

      

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