Analytical solution for consolidation of partially penetrated drainage columns composite foundation based on modified equal strain assumption

Partially penetrated drainage columns composite foundation has become a prevalent solution for improving soft grounds, particularly in scenarios where the soft soil strata are notably thick. The overall average consolidation degree stands as a pivotal metric for monitoring construction progression. Consequently, precise analytical solution for consolidation degree carries substantial engineering and scientific significance. Taking into account the deformation difference between the columns and its corresponding soil, the traditional equal strain assumption is modified. Incorporating factors such as the nonlinear horizontal permeability coefficient within the smeared zone, the consolidation characteristics of drainage columns and the underlying strata, a theoretical computation approach for determining the overall average consolidation degree of the partially penetrated drainage columns composite foundation is proposed based on the modified equal strain assumption. Through comparative analysis with numerical simulation outcomes and pre-existing solutions, the precision of the proposed methodology is verified. Moreover, a systematic parameter analysis is conducted, including column replacement ratio, penetration ratio, smear zone radius and other relevant factors. The results of comparative analysis and parametric study indicate that the method has extensive applicability and is helpful for consolidation degree calculation of the partially penetrated drainage columns composite foundation.