Abstract: The inflation ratio of different materials modified expansive soil was studied under the different mixing and overlying load. The results showed that four materials (lime, cement, fly ash, weathered sand) can effectively curb the expansive soil inflation ratio, different overlying load and different incorporation have great effects on the inflation ratio. With the increase in the load of the overlying, the inflation ratio of the improved expansive soil gradually decreases, which indicated that the overlying load can inhibit the expansion of expansive soil deformation. With the increase in the amount of incorporation of the respective materials, the inflation ratio decreases gradually, but the reduced amplitude was different. It can be seen from the analysis of the test data that  when the improved materials incorporation loads at all levels, weathered sand expansive soil improved the inflation ratio decreases the largest amount, followed by lime, cement, fly ash; when the overlying load increased from 0 to 75 kPa, the improved materials in different incorporation inflation ratio decreases the amount of lime, followed by cement, fly ash and weathered sand.