Optimal Design of Rigid Inclusions and Stone Columns Using Multiobjective Optimization

Abstract

Ground improvement adopting stone columns or rigid inclusions has become popular in engineering practice as it can be more economical under certain design criteria. In typical designs of either stone columns or rigid inclusions, the column diameter, column length, and grid spacing are three main parameters that affect the costs and performance of the improved ground. This work is concerned with achieving an optimal design for these two ground improvement methods. The design of the three main design parameters is subject to optimization using a multiobjective optimization algorithm with respect to minimizing the construction cost of the soil improvement system. We explain how the semiautomated design optimization works in connection with the considered calculation method used for the design and how execution constraints, if required, can be incorporated in the design workflow. Through the use of Priebe’s method and (ASIRI) recommendations for the calculation of stone columns and rigid inclusions, respectively, the usefulness of the presented design optimization approach for each of the two ground improvement methods is demonstrated.