A composite ground with partially penetrated granular columns is turned into a equivalent-double-layered ground on the basis of the general solution of the average degree of consolidation; and its simplifying analytical solution of 1D consolidation is worked out; furthermore

the simplifying formula of the average degree of consolidation is gained. Based on this solution

the present existing solutions and finite element method

these relevant programs are programmed. The consolidation process is investigated and the relevant results are prepared in graph forms which considering the influence of some factors including penetration ratio

permeability coefficient of a granular column

permeability coefficient of disturbed soil and impact factor of disturbed zone. The influence of various factors on the consolidation behavior of composite ground with partially penetrated granular columns is analyzed; and the comparative study of the average consolidation degrees by the three calculation methods is carried out; and then the applicability of the simplifying solution is discussed. The research results show that

the average consolidation degree of the simplifying solution under single-sided drainage or double-sided drainage conditions is between the ones of the existing solutions and the finite element method; and especially in the middle-latter of the consolidation process (≥50% degree of consolidation)

the results of the simplifying solution meet the engineering precision requirements; and it is simple

and practical; and in the various influencing factors

both length and permeability coefficient of granular column have the most effects on the consolidation process.