Abstract: Polyurethane is a kind of polymer, which can be used to improve the strength and integrity of material by filling pore and cementing soil particles. This paper used polyurethane to solidify the sea sand. The unconfined compressive strength tests and triaxial shear tests were designed to analyze the strength and deformation characteristics of solidified sea sand under different gelation time and different contents of curing agent. The experimental results show that with the increase of cementing time, the strength of solidified sea sand increases. More than 80% of the stable strength can be achieved at the solidification time of 3 hours. Moreover, the higher the mass ratio, the better the solidification effect. The polyurethane foam is filled into the pores, which increases the bite force between particles and enhances cohesion. The resistance of particle rearrangement increases, making the ability of sea sand to resist deformation become stronger, increasing the peak strength and changing the static properties.

Key words: polyurethane, sea sand, triaxial test, unconfined compressive strength