The frost heaving and thawing characteristics of dispersive clay in seasonal frozen soil region of China were studied by freezing-thawing test with different initial moisture contents

dry densities

and multiple freezing-thawing cycles. Results show that the freezing-thawing characteristics of dispersive clay were significantly different from those of non-dispersive clay

and the frost heaving amount of dispersive clay was much larger than that of non-dispersive clay. After several cycles of freezing-thawing

the dispersive clay exhibited loose property after frost heaving

while the non-dispersive clay showed compaction property. The initial moisture content

dry density

and freezing-thawing times had great influence on the thawing settlement coefficient and frost heave rate. The larger the initial moisture content was

the larger the frost heaving amount and the thawing settlement were. After multiple freezing-thawing cycles

the internal moisture content of the dispersive clay was re-distributed

and the lower the initial moisture content was

the higher the percentage increase of moisture content was in the corresponding part. In the case of external water replenishment

the dispersive clay with higher initial moisture content exhibited strong frost heaving after more than two times of freezing-thawing. For dispersive clay with different dry densities

the thawing settlement coefficient increased with increasing numbers of freezing-thawing cycles

and then tended to be stable. The experiment results will provide guidance for the necessary measures to reduce freezing-thawing damages of dispersive clay in the construction of highways

railways

and water conservancy projects in the northern line of “Belt and Road” in Heilongjiang and Jilin provinces.