xi
Preface and Acknowledgments
to the First Edition
The use of depth vibrators for the improvement of soils that are unsuitable
as foundations for structures in their original state dates back to more than
70 years. Over the course of time, the deep vibratory methods have become
probably the most used dynamic in situ soil improvement methods today.
They have not only experienced a continuous development of plant and
equipment to carry it out in practice, but also design methods have been
proposed and refined to predict the degree of soil improvement that can be
achieved.
Today the importance of deep vibratory soil improvement is unrivalled
among modern foundation measures; the demand for in situ deep treatment
of soils that introduces, if any, only environmentally harmless materials
into the ground continues to increase with the rising level of awareness for
the environment. Continued development of plant and process controls has
resulted in considerable increase in production rates.
When looking at the design concepts in use today, the reader will realize
that experience with the system in different soil conditions still plays an
important role. Sand compaction, because of the relative simplicity and
convincing economy of the system, and the familiar testing methods for the
estimation of settlements have probably inhibited the development of theories that would allow the calculation of the improved properties of granular
material based upon the fundamentals of soil dynamics. Recent developments show encouraging attempts to correlate the characteristic motion of
the depth vibrator working in the ground with the achieved soil properties.
The composite system of vibro stone columns and the surrounding cohesive
soil has become a challenging field for engineers to apply finite element
analyses particularly to the foundation of more complex structures and
single foundations. This computational tool supports the designer in his
endeavor to find the most economical solution by optimizing the foundation system.
It was the son who encouraged the father to embark on this book project, after the latter had collected knowledge and experience in the field of
ground improvement over a period of almost 35 years of his professional
life. This book aims to give an insight into deep vibratory soil improvement
Preface and Acknowledgments
to the First Edition
The use of depth vibrators for the improvement of soils that are unsuitable
as foundations for structures in their original state dates back to more than
70 years. Over the course of time, the deep vibratory methods have become
probably the most used dynamic in situ soil improvement methods today.
They have not only experienced a continuous development of plant and
equipment to carry it out in practice, but also design methods have been
proposed and refined to predict the degree of soil improvement that can be
achieved.
Today the importance of deep vibratory soil improvement is unrivalled
among modern foundation measures; the demand for in situ deep treatment
of soils that introduces, if any, only environmentally harmless materials
into the ground continues to increase with the rising level of awareness for
the environment. Continued development of plant and process controls has
resulted in considerable increase in production rates.
When looking at the design concepts in use today, the reader will realize
that experience with the system in different soil conditions still plays an
important role. Sand compaction, because of the relative simplicity and
convincing economy of the system, and the familiar testing methods for the
estimation of settlements have probably inhibited the development of theories that would allow the calculation of the improved properties of granular
material based upon the fundamentals of soil dynamics. Recent developments show encouraging attempts to correlate the characteristic motion of
the depth vibrator working in the ground with the achieved soil properties.
The composite system of vibro stone columns and the surrounding cohesive
soil has become a challenging field for engineers to apply finite element
analyses particularly to the foundation of more complex structures and
single foundations. This computational tool supports the designer in his
endeavor to find the most economical solution by optimizing the foundation system.
It was the son who encouraged the father to embark on this book project, after the latter had collected knowledge and experience in the field of
ground improvement over a period of almost 35 years of his professional
life. This book aims to give an insight into deep vibratory soil improvement