The pile-soil stress ratio is an important parameter depicting the work state of composite foundation. Lots of theoretical researches were carried out in recent years; but they were usually deduced on the condition of laying sand cushion. Under the load from embankment

the capping plate is set at the top of grouting pile. Based on this especial condition

a proper theoretical model is brought forward. Furthermore

limit equilibrium theory and elastic theory are adopted to deduce the formula of pile-soil stress ratio of grouting gravel pile composite foundation under embankment load; and it is validated by project actual measurement and instruct the design of grouting gravel pile composite foundation.