Review of Soil Improvement Techniques

Foundation designers use deep foundation, when shallow foundation proved to have inadequate bearing capacity for the loading conditions, or the total and differential settlements are intolerable for the given structure. As an alternative approach, designers may consider one of the many soil improvement techniques to improve the geotechnical quality of the ground, i.e. bearing capacity and settlement characteristics. In choosing a soil improvement techniques, several factors should be considered including the suitability of the technique for the soil in place, the associate cost beside the durability and its performance over the year for the given load and geometry. These techniques may be used as a solution for problems in the ground for both existing and new constructions. However, there are several considerations, which engineers must examine before adopting any of these methods. This paper presents a review of the available soil improvement techniques, including their advantages, disadvantages/limitations, and provide applicability guide to practicing engineers for a given soil conditions and field applications. Design case study is presented proposing compaction grouting technique to overcome the collapse of bored piles. Selected field case studies from literature have been also presented using different soil improvement techniques explaining the improvement achieved from using each technique.