Local triaxial test method for bituminous mixture and radial displacement test device for bituminous mixture

The invention discloses a radial displacement test device which comprises a ring-shaped chain connection pipe, pulleys, a spring, an adjustment bolt, an adjustment bolt fixing device, a fixing screw I, a fixing screw II, a linear displacement sensor fixing device and linear displacement sensors. The invention also discloses a local triaxial test method for a bituminous mixture. Two linear variable differential transformers (LVDT) are mounted and are used for measuring axial strain; one LVDT for measuring radial strain can be used for measuring radial and axial deformations of the bituminous mixture, namely measuring radial expansion deformation and axial contraction deformation of a bituminous mixture test piece. The local triaxial test method and the radial displacement test device provided by the invention can be used for testing the shear performance of a bituminous pavement and simulating an actual pavement which is horizontally changed along with the type, the temperature and the stress of the mixture; furthermore, a corresponding test method, a principle, operating steps and the like are provided; the test method and the device have extremely high generalization performance.