Theoretical Analysis And In-situ Tests Of CSP Composite Ground

The lower allowable bearing capacity and intolerable settlements are often encountered during construction of expressways in soft soil areas. Cement soil pile (CSP) composite ground has been proved to be an effective way to improve the ground?performance. In this paper both plate loading test and FEM are employed to investigate the CSP composite ground抯 working characteric and reinforcing mechanism. Settlement calculation formulas for both bearing type and friction type CSP are also derived theoretically. Furthermore, a simplified analysis model based on Winkler assumption for CSP composite ground is developed. In the light of the research conducted, it is understood that the depth of soft soil and bearing capacity of underlying stratum significantly affects the efficiency of CSP composite ground. As a case study, a CSP composite ground on Beijing-Shenyang Expressway (Langfang section) is discussed.