Natural gas hydrate is one of the most important potential energy sources

which is a triggering factor of global climate change and geologic hazards. It is necessary to research engineering characteristic of hydrate-bearing sediment to insure the exploiture of hydrate successfully.A triaxial shear apparatus devoloped by ourselves was used to test the deformation and failure behaviors of sand with different hydrate content controled by different original water content. As a result

it is found that the shear modulus of hydrate-bearing sand increased sharply because of samples filled and cemented by hydrate in pore

and original shear modulus of samples increased with increment of hydrate content at the same confining pressure in hyperbolic model. Friction angle increases with increment of hydrate contents slightly; however compared with the samples contained 31.0% and 51.0% hydrate

cohesion of the former two groups are much more than the latter two.Thus the constribution of strength increment is the cementation of hydrate on grains

and the effect is controlled by content and distribution of hydrate in samples.