The Theoretical And Experimental Study Of Glass Fiber Improve Asphalt Concrete

The fiber-asphalt concrete is the kind of asphalt mixture added appropriate amount of fiber. The effect of reinforced is related closely to the fibers performance. If the fibers have good cohesion with the concrete and the fibers are distributed uniformly over the concrete, the tensile stress will be transferred through the fibers, which play the role of bridge and cracking resistance, that can reduce the cracks on the asphalt-mixture pavement. Meantime fibers have a certain adsorption to asphalt which can decrease the phenomenon of bleeding. Glass fiber is the cheapest fiber material in the market, correspondingly it has some shortage. If we put the rough fiber in the asphalt concrete, the fiber perhaps be bent under the situation of intersect because of its rigid and brittle function and, which can cause poor endurance as well. On the contrary, if the concrete, although their flexible performance is well, but they are easily mat each other after be heated, and that make it is difficult to disperse them while stirring. Nowadays, there are not the fibers which are specialized for the asphalt pavements. If we have methods to improve the quality along its interface, and reduce the static electricity, then the combine between fibers and asphalt can be stronger. The result is lessening cost and increasing effectiveness. This material and technology have a wide vista and play an important role to the development of highway.Glass fiber is a non-mentallic inorganic material with excellent performance Its raw materials are nature ore such as silica sand, limestone, borocalcite, fluorite and so on. People grind them into powder, calculate a rational ratio of every raw material, and mix them accurately, then the materials are put in a special kiln to melt to a molten glass state, then pull the molten glass with the external force, and then blowing or fling them to scrappy fibers. Because of its advantage, such as resistance to effect of heat, resistance to chemical attack, high tensile-strength and impact strength, low breaking elongation, heat insulation and insulativity are also well, the glass fiber is served for the reinforcer to polymeric material and non-metallic inorganic materials and their composite materials. The experiments indicate the good enhancement effect. But there are a lot of microcosmic defects on the surface of the undressed glass fiber stochasticly, which make the fiber rupture brittly easily. The strength show a biggish dispersivity, that drop the whole mechanical property of the glass fiber reinforce composite material conduction. So in the process of producting glass fiber, people handle the surface as a significant method, which can effectively repair the defects on the surface of the fiber, and improve the surface performance, the felt between the fiber and the kinetosome is alsoimproved. To handle the surface of the glass fiber with resin acceptor will improve the performance of the glass fiber effectively.The resin acceptor is a kind of matter with amphiprotic structure. Some radicals in the molecule will react with the chemical radical (hydroxide radical) on the mineral surface, the reaction will product a firm chemical bond; another radicals has the characteristic the organic matters have, they can intertwine or react with the organic molecules. This characteristic of the fiber can combine two materials with different natures. The resin acceptor can generates shells with cross-linked structure around the glass fibers, the shells can remove the moisture of the fiber surface, repair the scrappy injury inside the glass fiber, and it is widely used to handle the surface of the glass fiber.This article researches the following aspects depending on the interrelated knowledge to the highway subject, instruction material, surface physical chemistry, composite materials. To introduce a new method of producting the glass fiber-tank furnace method; to analysis and research the reaction mechanism between the resin acceptor and the glass fiber; to make the choice of the resin acceptor depending on the molecule structure of the bituminiferous constituents; to calculate the amount of the resin acceptor by theory formula; to handle the surface of the glass fiber via using the resin acceptor and anlistatig; to analysis the interface between the bituminous and the glass fibers under the action of the resin acceptor by means of the infra-red spectrum; to research the asphalt mixture's improvement in the performance which is caused by the glass fiber.I have researched the reaction mechanism between the silicon-resin acceptor and the glass fiber through the theory of surface physical chemistry. Silane resin acceptor X-radical hydrolyze to alkylsilanol, there are hydrogen bonds inside the silicon–hydroxide radical and inside the silane-hydroxide radical, silicon-hydroxide radical dehydrate to the bond such as–Si-O-Si–. Then silane resin acceptor and glass fiber combine through the–Si-O-Si–, meantime, the silane fasculate to a film in the surface of the glass fiber. We used the Nicolet 360 Fourier transform infrared spectrometer to accomplish the experiment, we get the spectrum of the glass fiber which is treated by the resin acceptor, spectrum of the asphalt and that after the glass fiber dipped in the asphalt. To analysis the surface between the glass fiber treaded and the asphalt via contrasting the spectrogram, and then we know that there is no chemical reaction between the resin acceptor and the asphalt, instead of a kind of physical adsorption.Simultaneously, I have contrasted the service performance of the AC-13I asphalt mixture to that incorporated different amount of glass fiber, and I get the following result:(1)In the wake of the increasing of the amount of the glass fiber, the density of the asphalt mixture and the Marshall stability are reduced while the poriness and the flow value are raised. In the process of construction, we have to consider the characteristic of the glass fiber mixture and the compaction effect when we spread concrete and roller compaction.(2)The dynamic stiffness is increased because of mixing glass fiber into the mixture, as well as the tension set is decreased and it can reduce the track.(3)The hydrostatic stability is obviously improved while we added 0.2% glass fiber, the indirect tensile strength after freeze thawing of the check bar is increased 9.7%, the indirect tensile strength ratio is up 3.5%, that delicate the glass fiber can improve the binding power of the asphalt and felt the asphalt and aggregate more stable. But when we add 3.0% glass fiber in the mixture, the freeze thawing splitting strength ratio and the freeze thawing indirect tensile strength are lower than the mixture without the glass fiber, that means that overmuch glass fiber block the asphalt contacting to the aggregate, which effect the densify of the asphalt mixture and decrease the hydrostatic stability.The research of the surface between the glass fiber and the asphalt in the asphalt mixture is a new research field in the road construction stuff filed , there is no a mature theory in this filed. This article is relevant to the technology of the surface physical chemistry and the surface resin acceptor, plainly analysis the reaction mechanism between the resin acceptor and the glass fiber when we handle the surface of the glass fiber, and finally give the method of choosing the resin acceptor. Because of the limitation of the time, energy and the conditions of the tests, what I did is just the beginning of the research of the resin acceptor'actions to the glass fiber and asphalt, but the results can supply some experience and methods to the further research.