The invention discloses a calculation method for a piled raft infrastructure. The calculation method comprises the following steps: firstly, stiffness calculation: a, under the condition that the
bearing capacity of earth among piles is not considered, a
pile foundation can be simulated as a spring, and the spring stiffness kpi of the foundation
pile can be expressed by the ratio of the
pile top load Qdi to the pile top settlement si; b, the combined action of the piles and the earth is considered, the load borne by the earth among the piles is about 15 percent of the total load; secondly, infrastructure calculation: for foundations simulated by adopting spring supporting seats, each spring supporting seat is used as a unit, the units are integrated according to certain conditions, and a total
stiffness matrix is formed by assembling unit stiffness matrixes. The spring supporting seats are adopted for simulating the foundations of the pile foundations and common settlement in the
engineering is used for analyzing, so that the defect that part of parameters is difficult to determine by an elastic method is overcome; by adopting spring models which are close to actual conditions of the interaction of the pile earth and the structure, the calculating
workload is small, the calculation is convenient, and the calculation result accords with the requirement of
engineering design.