In practical engineering

the foundation is usually untreated

natural and heterogeneous. The phenomenon that threshold hydraulic gradient exists in clayey soil under low hydraulic gradient is gradually recognized. However

the consolidation model of heterogeneous foundations considering threshold hydraulic gradient is rarely reported. In this paper

based on seepage model considering threshold hydraulic gradient

the consolidation problem of heterogeneous foundation was studied

the change law of compressive modulus and permeability coefficient with depth under variable loads were obtained. One-dimensional consolidation model of single-layer

heterogeneous foundation was established with an assumption that the compression modulus increases with depth

and the permeability coefficient decreases with depth. The influence of threshold hydraulic gradient i

0

heterogeneous foundation parameter a

x

m and p on the consolidation characteristics of heterogeneous foundation were analyzed. The results show that

the rate of pore pressure dissipation becomes slower in heterogeneous foundation after considering threshold hydraulic gradient and settlement as well as consolidation rate of the foundation decreases accordingly. The consolidation rate is directly proportional to the value of a and x while the final settlement of the foundation comes inversely proportional to them. The consolidation rate grows with the increase of m and the decrease of p. However

the permeability coefficient may only change the settlement rate of foundation

which will not affect the final settlement of the heterogeneous foundations.