1
Chapter 1
An overview of deep
soil improvement by
vibratory methods
Realization of structures always makes use of the soil on which, in which,
or with which they are built. Whenever engineers find that the natural conditions of the soil are inadequate for the envisaged work, they are faced
with the following well-known alternatives of
1. Bypassing the unsuitable soil in choosing a deep foundation.
2. Removing the bad soil and replacing it with the appropriate soil.
3. Redesigning the structure for these conditions.
4. Improving these conditions to the necessary extent.
When the Committee on Placement and Improvement of Soils of the
ASCE’s Geotechnical Engineering Division published its report Soil
Improvement: History, Capabilities, and Outlook in 1978, it concluded
that “it is likely that the importance of the fourth alternative will increase
in the future” (p. 1). Indeed, in the decades since “the need for practical,
efficient, economical, and environmentally acceptable means for improving unsuitable soils and sites” (p. 3) has increased.
Before selecting the appropriate soil improvement measures, it is necessary to determine the requirements, which follow from the ultimate and
serviceability limit state of design. These are
• Increase of density and shear strength with a positive effect on stability problems.
• Reduction of compressibility with a positive effect on deformations.
• Reduction/increase of permeability to reduce water flow and/or to
accelerate consolidation.
• Improvement of homogeneity to equalize deformation.
When leaving aside the method of exchanging the soil, ground improvement can be categorized into compaction and reinforcement methods.
Table 1.1 shows a classification of the methods of ground improvement
that are of practical relevance today.
DOI: 10.1201/9781315372341-1
Chapter 1
An overview of deep
soil improvement by
vibratory methods
Realization of structures always makes use of the soil on which, in which,
or with which they are built. Whenever engineers find that the natural conditions of the soil are inadequate for the envisaged work, they are faced
with the following well-known alternatives of
1. Bypassing the unsuitable soil in choosing a deep foundation.
2. Removing the bad soil and replacing it with the appropriate soil.
3. Redesigning the structure for these conditions.
4. Improving these conditions to the necessary extent.
When the Committee on Placement and Improvement of Soils of the
ASCE’s Geotechnical Engineering Division published its report Soil
Improvement: History, Capabilities, and Outlook in 1978, it concluded
that “it is likely that the importance of the fourth alternative will increase
in the future” (p. 1). Indeed, in the decades since “the need for practical,
efficient, economical, and environmentally acceptable means for improving unsuitable soils and sites” (p. 3) has increased.
Before selecting the appropriate soil improvement measures, it is necessary to determine the requirements, which follow from the ultimate and
serviceability limit state of design. These are
• Increase of density and shear strength with a positive effect on stability problems.
• Reduction of compressibility with a positive effect on deformations.
• Reduction/increase of permeability to reduce water flow and/or to
accelerate consolidation.
• Improvement of homogeneity to equalize deformation.
When leaving aside the method of exchanging the soil, ground improvement can be categorized into compaction and reinforcement methods.
Table 1.1 shows a classification of the methods of ground improvement
that are of practical relevance today.
DOI: 10.1201/9781315372341-1