Device and method for direct tensile test of pavement materials avoiding eccentric tension

Abstract

The invention provides a pavement material direct tensile test apparatus with eccentric tension avoided and method thereof, and the apparatus comprises a test part, a detected part installed in the test part, and electromagnetic force control part, wherein, the test part comprises a hinged base on the spherical shape, and a spherical lower hinged base matched with the spherical upper hinged base, and the spherical upper hinged base is installed with a upper link which is connected to a mechanics test and simulation testing machine, and the spherical lower hinged base is connected with a cast iron block by the lower pull bar, and the test part is installed between the spherical upper hinged base and the spherical lower hinged base; the electromagnetic force control part is connected with the cast iron block. Because of the flexibly rotary spherical hinged base, in the test process, when the test part is tensioned, the test part can naturally drop depending on gravity, thereby the eccentric force being effected on the detected part during tensile test is avoided, and the test result is more accurate, in addition, the invention has the advantages of simple structure, convenient operation, economic utility, reliable test data provision and minimized test error.

Description

technical field [0001] The present invention relates to the field of direct tension test for fatigue cracking life prediction research of road surface materials such as asphalt mixture, inorganic binder stabilized pellets, etc. . Background technique [0002] The direct tensile test can be used to evaluate the low-temperature crack resistance of asphalt mixture, and the size of the specimen is 38.1mm×38.1mm×101.6mm. The test system is loaded under low temperature conditions at a slow tensile rate, and the cracking temperature can be estimated from the strength-temperature relationship curve obtained through the test; the stress-plastic strain relationship of the asphalt mixture can also be determined by direct tensile tests, so that The relationship between local strain and fatigue life is established to estimate the fatigue cracking life of asphalt pavement. The size of the specimen is 50mm×50mm×250mm. [0003] However, in these two tests, the trabecular specimen is fixed...

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Problems solved by technology

[0003] However, in these two tests, the trabecular specimen is fixed on the fixture, because the iron sheets on the upper and lower sides of the trabecular specimen may not be parallel after being adhered, which causes the trabecular specimen to be subjected to tension during stretching. The effect of eccentric tension will make the actual test results obtained inconsistent with the expected test results, resulting in inaccurate test data and cannot be used

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