A test device for compressive torsional shear failure performance of asphalt mixture

Abstract

The invention belongs to the technical field of asphalt mixture shear behavior testing, and relates to a testing device of the pressure-torsion shear failure performance of an asphalt mixture. The device provides a constant-temperature environment through an outer circulating heat preservation system and exerts axial pressure and torsion loads on asphalt mixture test pieces in an independent or combination mode. A dual-layer plane ball bearing is arranged, transmits axial pressure to a left fixed plate and releases torsion loads; a square-section section is arranged at the right end of an axial pressure loading shaft, and torsion loads are borne by a square hole of a right fixed plate; a spring is arranged to buffer axial pressure loads. A torque sensor and a pressure sensor which are completely separated spatially are adopted, the measuring ranges of the two sensors do not need to be matched, and the two sensors do not influence each other. By means of the device, the failure process of the asphalt mixture in the moderate and high temperature environment and the complicated torsion stress state can be simulated; when the torsion loads continuously change, the direction of the main stress axis of a test piece continuously changes, and the change characteristic of the real stress state of a road surface is met.

Description

technical field [0001] The invention belongs to the technical field of asphalt mixture anti-shear mechanical performance test, and relates to an asphalt mixture compression-torsion shear failure performance test device, which is a kind of asphalt mixture under the compression-torsion complex stress state and medium-high temperature environment. Cutting fracture strength performance test device. Background technique [0002] Faced with increasing traffic volume and overloading during road use, the shear strength of asphalt mixture at high temperature is not enough to resist the repeated action of wheel loads, causing plastic shear deformation of asphalt concrete and rutting damage. The direct reason is that the high temperature stability of asphalt mixture is insufficient, and the shear resistance is an important factor affecting the thermal stability of asphalt mixture. However, the torsional shear failure performance test under pressure can reflect the real situation of pa...

AI Technical Summary

Problems solved by technology

Its main disadvantages are: due to the lack of axial pressure, the test specimen is in a state of pure shear stress, and its maximum tensile stress is equal to the maximum shear stress. For materials whose tensile strength is less than the shear strength, the specimen will be damaged by tension instead of shear failure

The current test devices and test methods cannot realize the true simulation of the stress state of pavement materials under traffic loads

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