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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris2013
Controversial and Contradictory Evaluations in Analyses of Ground Vibrations
from Pile Driving
Évaluations controversées et contradictoires dans l'analyse des vibrations de terre
par suite de l'enfoncement de pieux
Svinkin M.R.
VIBRACONSULT, Cleveland, USA
ABSTRACT: Pile driving operations are powerful and wide-spread sources of construction vibrations which may detrimentally
affect adjacent and remote structures, make obstacles for operating sensitive processes and devices, and disturb people. A number of
factors can affect ground vibration from pile installation. Wave propagation from pile driving is a complicated problem, and
different approaches are utilized to analyze this phenomenon. A paper presents several controversial and contradictory issues in
assessment of ground vibrations generated by pile driving such as connections between wave propagation in piles and ground
vibrations, the relationship between pile impedance and intensity of ground vibrations, effects of the hammer energy on ground
vibrations and a possible correlation between pile capacity and ground vibrations. Also, it is important to show the inadequate roles
of condition surveys of structures and monitoring of ground vibrations and the necessity to properly assess crack changes in
condition surveys. Analysis and clarification of various approaches are important for practical applications.
RÉSUMÉ: Les opérations d’enfoncement de pieux sont des sources puissantes et très répandues de vibrations de construction qui
pourraient affecter de façon nuisible des structures adjacentes et éloignées, faire obstacle à l’utilisation de procédés et d’appareils
sensibles, et perturber des gens. De nombreux facteurs peuvent affecter la vibration du sol par suite de l'installation de pieux. La
propagation d’ondes causée par l’enfoncement de pieux est un problème compliqué, et diverses méthodes sont utilisées pour
analyser ce phénomène. Cet article présente plusieurs points controversés et contradictoires dans l’évaluation des vibrations de sol
générées par l’enfoncement de pieux, telles que des connections entre la propagation des ondes dans les pieux et les vibrations de
sol ; les rapports entre l'impédance des pieux et l’intensité des vibrations de terre ; des effets de l’énergie percutante sur des
vibrations de sol, et une corrélation possible entre la capacité des pieux et les vibrations de sol. De plus, il est important de montrer
le rôle inadapté des conditions de surveillance des structures, du contrôle des vibrations de sol et la nécessité d'évaluer les
modifications des fissures par les opérations de contrôle. L'analyse et la clarification de diverses méthodes sont importantes pour des
applications pratiques.
KEYWORDS: pile driving, ground vibrations, stress wave theory, impedance, energy, survey
1. INTRODUCTION
Installation of driven piles creates soil vibrations and
displacements which may affect adjacent and remote
structures, people and sensitive equipment. Therefore, various
approaches are used for evaluation of vibration effects of pile
driving.
There is a trend to connect stress-wave propagation in piles
during pile driving with prediction or calculation of the peak
particle velocity (PPV) of ground vibrations from pile
installation. However, there are ambiguous problems in using
of this approach for assessment of ground vibrations.
Pile impedance affects force and velocity at the pile head in
opposite ways at the same time. Therefore, the pile impedance
effect on the intensity of ground vibrations is not obvious.
Pile driving generates ground vibrations due to the hammer
energy applied to a pile, but some case histories demonstrate
no correlations between the hammer energy and the maximum
velocity of ground vibrations. Other factors such as the depth
of pile penetration into the ground and soil resistance to pile
driving should be taken into account.
The relationship between pile capacity and ground
vibrations is not clear. Moreover, pile capacity and ground
vibrations are outcomes of pile driving and only an accidental
correlation between them is possible. For sure, both variables
are dependent on the hammer energy.
On the one hand approximate calculation of expected
ground vibrations and even vibration monitoring yield relative
information on vibration effects on structures, and these results
could be inconclusive. On the other hand condition surveys of
structures before, during, and after pile driving provide complete
information on structural responses to vibration excitations and
this information can be much beneficial than vibration assessment
and measurements.
Clarifications of different ways used for analyses of pile
driving as the source of construction vibrations, ground vibrations
generated by pile driving and various effects of these ground
vibrations on structures, people and sensitive devices are
important to understand the problem and prevent harmful
consequences of pile driving operations.
2. STRESS-WAVES PROPAGATION IN PILES AND
GROUND VIBRATIONS
For about forty years, the stress-wave theory is successfully
used for driveability analysis of driven piles and also for
determination of pile capacity at the time of testing, for
example Proceedings of IS-Kanazawa 2012 (2012). In recent
years, there is a trend to connect stress-wave propagation in
