Optimized design of foundations on soil reinforced by floating columns

Abstract

AbstractThis paper studies the reinforcement of very thick compressible soft soil layer by floating columns. Analysis is made on the basis of recent methodology of design that combines the bearing capacity and settlement verifications to provide the optimized improved area ratio. Introducing the allowable long term settlement of unreinforced compressible soil and assuming that the short term total settlement is completed at the end of construction an optimized length of floating columns is obtained. The discussion of this method of design highlights the feasibility of a potential solution of reinforcement in making a whole cost effective design both including the improvement area ratio within the reinforced upper layer and the thickness of the soft clay. Design charts are proposed for soft clays reinforced by floating columns. Illustration by a case study highlighted the efficiency of floating columns.