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Numerical analysis of vibrations due to impact pile driving

Andersson Olivecrona, Sebastian LU and Sulander, Rasmus (2016) In TVGT-5000 VGTM01 20161
Geotechnical Engineering
Department of Construction Sciences
Abstract
Vibrations originating from constructional work can affect the nearby soil and structures. Depending on the properties of the vibrations, these can result in settlements in the soil and damages to existing structures. Along with blasting, impact pile driving is one of the greatest sources of vibrations on a construction site.

When installing a concrete pile with an impact hammer, a weight is dropped at the head of the pile repeatedly until the pile is located in a desired position. The mechanism of load transfer from pile to soil decides whether the pile should be grouped as a friction pile, cohesion pile or an end bearing pile. When the pile is installed in a granular soil the resistance force along the shaft of the pile depends on the... (More)
Vibrations originating from constructional work can affect the nearby soil and structures. Depending on the properties of the vibrations, these can result in settlements in the soil and damages to existing structures. Along with blasting, impact pile driving is one of the greatest sources of vibrations on a construction site.

When installing a concrete pile with an impact hammer, a weight is dropped at the head of the pile repeatedly until the pile is located in a desired position. The mechanism of load transfer from pile to soil decides whether the pile should be grouped as a friction pile, cohesion pile or an end bearing pile. When the pile is installed in a granular soil the resistance force along the shaft of the pile depends on the horizontal stress and the angle of friction between the pile and the soil. While installing a pile in a cohesion soil, the adhesion between pile and soil cannot be utilised since the soil is remoulded during pile driving.

Important soil properties that affect the vibration propagation in the soil are density, Young’s modulus, Poisson’s ratio and the stress state of the soil. Volume changes in the soil can occur if the soil is exposed to vibrations. The magnitude of the volume change is dependent on the angle of dilatation and the initial porosity. The three most common types of waves that propagate through the soil are the pressure wave, the shear wave and the Rayleigh wave.

In this report, the vibrations of a single hammer blow at different pile depths are studied and compared with a field test. The object is to investigate the possibility to make a satisfactory finite element simulation of the vibrations due to pile driving. Two soil plasticity models are used along with a linear elastic model. The plastic models are the Mohr-Coulomb yield criterion and the Drucker-Prager yield criterion.

No significant discrepancies were found in the vibration velocities in the different material models. Although, small differences in vibrations occur with the plastic Drucker-Prager model in comparison with the elastic model. Results show that the Young’s modulus for a soil is decisive for the behaviour and magnitude of the vibrations.

The conclusion is that the finite element method can be successfully used to predict wave propagation and vibrations due to impact pile driving, regardless of which of the three material models that are used in the computation. Predicting the waves and vibrations can be a useful tool for reducing noise, settlements, damage and unpleasantness associated with pile installations. (Less)
Popular Abstract
Vibrations deriving from constructional work can affect the nearby soil and structures. Depending of the properties of the vibrations, these can result in settlements in the soil and damages to existing structures. Along with blasting, impact pile driving is one of the greatest source of vibration on a construction site.
Please use this url to cite or link to this publication:
author
Andersson Olivecrona, Sebastian LU and Sulander, Rasmus
supervisor
organization
course
VGTM01 20161
year
type
H3 - Professional qualifications (4 Years - )
subject
keywords
Finite element method, Concrete pile, Impact pile driving, Ground vibrations, Soil mechanics, Soil dynamics, COMSOL Multiphysics
publication/series
TVGT-5000
report number
TVGT-5058
ISSN
0349-4977
language
English
id
8888028
alternative location
http://www.geoteknik.lth.se/english/publications/masters-dissertations/
date added to LUP
2016-08-11 18:06:04
date last changed
2016-08-11 18:06:04
@misc{8888028,
  abstract     = {Vibrations originating from constructional work can affect the nearby soil and structures. Depending on the properties of the vibrations, these can result in settlements in the soil and damages to existing structures. Along with blasting, impact pile driving is one of the greatest sources of vibrations on a construction site.

When installing a concrete pile with an impact hammer, a weight is dropped at the head of the pile repeatedly until the pile is located in a desired position. The mechanism of load transfer from pile to soil decides whether the pile should be grouped as a friction pile, cohesion pile or an end bearing pile. When the pile is installed in a granular soil the resistance force along the shaft of the pile depends on the horizontal stress and the angle of friction between the pile and the soil. While installing a pile in a cohesion soil, the adhesion between pile and soil cannot be utilised since the soil is remoulded during pile driving.

Important soil properties that affect the vibration propagation in the soil are density, Young’s modulus, Poisson’s ratio and the stress state of the soil. Volume changes in the soil can occur if the soil is exposed to vibrations. The magnitude of the volume change is dependent on the angle of dilatation and the initial porosity. The three most common types of waves that propagate through the soil are the pressure wave, the shear wave and the Rayleigh wave.

In this report, the vibrations of a single hammer blow at different pile depths are studied and compared with a field test. The object is to investigate the possibility to make a satisfactory finite element simulation of the vibrations due to pile driving. Two soil plasticity models are used along with a linear elastic model. The plastic models are the Mohr-Coulomb yield criterion and the Drucker-Prager yield criterion.

No significant discrepancies were found in the vibration velocities in the different material models. Although, small differences in vibrations occur with the plastic Drucker-Prager model in comparison with the elastic model. Results show that the Young’s modulus for a soil is decisive for the behaviour and magnitude of the vibrations.

The conclusion is that the finite element method can be successfully used to predict wave propagation and vibrations due to impact pile driving, regardless of which of the three material models that are used in the computation. Predicting the waves and vibrations can be a useful tool for reducing noise, settlements, damage and unpleasantness associated with pile installations.},
  author       = {Andersson Olivecrona, Sebastian and Sulander, Rasmus},
  issn         = {0349-4977},
  keyword      = {Finite element method,Concrete pile,Impact pile driving,Ground vibrations,Soil mechanics,Soil dynamics,COMSOL Multiphysics},
  language     = {eng},
  note         = {Student Paper},
  series       = {TVGT-5000},
  title        = {Numerical analysis of vibrations due to impact pile driving},
  year         = {2016},
}