Device and method for testing anti-icing performance of asphalt mixture

Abstract

The invention discloses a device for testing anti-icing performance of an asphalt mixture. The device comprises a top cover, a hollow sleeve and a disc from top to bottom, the top of the top cover is provided with a water injection pipe, the top of the disc is provided with an opening, the sleeve is also provided with a concave base, the inner side wall of the sleeve is provided with a thread, the upper section and the lower section of the outer side wall of the sleeve are both provided with threads, the disc is provided with a large round mouth and a small round mouth from top to bottom, the inner walls of the large round mouth and the small round mouth are both provided with threads, the thread of the upper section of the outer side wall of the sleeve is matched with the thread of the inner side wall of the top cover, and the thread of the lower section of the outer side wall of the sleeve is respectively matched with the thread on the inner side wall of the concave base and the thread on the inner wall of the large round mouth of the upper section of the disc. The device overcomes the defect of inaccurate bond strength testing caused by interface damage, uncontrollable drawing area and the like of ice and the mixture of the method in the prior art, and solves the problem that the method in the prior art is not suitable for open-graded and semi-open-graded asphalt mixtures.

Description

technical field [0001] The invention belongs to the technical field of asphalt pavement function evaluation, in particular to a test device and method for ice-phobic performance of asphalt mixture. Background technique [0002] Melting snow and ice has become a new function of asphalt pavement in some areas. With the rapid development of highway construction, the attributes of highways have been improved from the aspects of all-weather smoothness, high speed, and durability to higher levels such as environmental protection, energy saving, and safety. A variety of new functions, such as: a new road surface with the function of degrading automobile exhaust; a new road surface with rapid drainage, noise reduction, and anti-skid functions; a colored road surface with traffic induction functions; Among them, the snow-melting and ice-melting function of asphalt pavement has become a research hotspot in recent years because of the vast territory of our country and the frequent occ...

AI Technical Summary

Problems solved by technology

[0005] Although the above two tests can evaluate the ice-phobicity of the mixture to a certain extent, their defects cannot be ignored, as follows: (1) After freezing, it is necessary to remove the mold to obtain the composite specimen of ice-asphalt mixture. During the process, the friction between the ice and the mold and the friction between the ice and the demoulding device are easy to occur, which often leads to the separation of the ice and the asphalt mixture, such as figure 1 As shown, the asphalt mixture specimen 3 is separated from the ice cube 2 on it, which makes it impossible to accurately measure the bond strength between the ice and the mixture when the embedded part 1 is drawn

In fact, even if the ice is not separated from the mixture, it is still a complete composite specimen, and interlayer damage may occur during the demolding process, which affects the accuracy of the pull-out force and ice-breaking force tests

(2) In the pull-out test, after the embedded parts are pulled out, sometimes more ice is pulled out, sometimes less, which is uncontrollable, such as figure 2 As shown, the embedded part 1 is embedded in the separated ice cube 2 to form a drawn area 4, and the measured pulling force at this time includes not only the bonding force between the ice and the mixture, but also the embedded The resistance of the ice on the upper part of the part to the embedded part, so the pull-out test cannot obtain the pure bond strength between the ice and the mixture

(3) Porous asphalt mixture can seep water due to its rich interconnected pores, so it is impossible to realize the process of water injection and freezing on the upper part without demoulding, that is, the molding of the above composite specimen is only suitable for asphalt mixture with dense gradation and low porosity , not applicable to semi-open gradation and open gradation porous asphalt mixture

Therefore, the existing test devices and methods for the bonding effect between asphalt mixture and ice layer have defects, and are not suitable for evaluating the ice-phobicity of the mixture.

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