Microcosmic Analysis And Performance Research Of Basalt Fiber Asphalt Concrete

Basalt fiber performance research of asphalt concrete reinforced with reinforcingmechanism of microcosmic analysis With its unique performance of asphalt pavement inhigh grade highway in the possession of absolute advantage. With the development ofeconomy and modern research advances in technology of asphalt pavement material,durability, crack resistance, temperature stability, put forward more and more requirements.This requires from the material strength of the basic parameter of the decision, from thematerial itself and the composition and mechanical properties of sets out, to its durability,crack resistance, thermal stability and viscoelastic and so on.Basalt fiber for its excellent physical and chemical properties, widely used in aviation,conduit, dam etc.. Basalt fiber in the whole production process and application, no pollutionto environment, and aggregate in composition there is no big difference, is integrated withthe asphalt volume of different shapes, the basalt fiber into the asphalt concrete of thefeasibility and superiority of asphalt binding.Basalt fiber in concrete applications have achieved good results, but for the asphaltconcrete application research is not thorough. As a result of the basalt fiber in asphaltconcrete on mechanical properties of different from the polymer modified asphalt concrete,basalt fiber length and volume are on asphalt concrete before and after cracking performance,mechanical behavior, viscoelastic mechanical properties have obvious effect. Therefore, thebasalt fiber performance of asphalt concrete and reinforcing mechanism research, will behelpful to the reasonable selection of fiber length and fiber content, clear the basalt fibermicro distribution of macroscopic properties of the mechanism of the effect of the fiberasphalt concrete, which play a stable enhanced performance has very important significance.This article from the basalt fiber of different length, different content sets out,undertook the following related research:(1) The basalt fiber asphalt concrete temperature stability, fatigue resistance, toughness and viscoelastic properties before, using indirect tensile test, the splitting tensile strength forevaluating targets to roughly delineated basalt fiber length and the corresponding range ofdosage, initial is selected depending on the length of the basalt fiber on asphalt concretematrix enhanced performance.(2) In order to identify the different length, different content of basalt fiber on asphaltconcrete practical improvement effect, separately for different length, different content ofbasalt fiber water stability, high temperature performance, low temperature performance testresearch, according to the results of analysis and comparison of different length of the basaltfiber and the reinforcing effect of contribution, to further define the basalt fiber length andthe corresponding amount of value rationality.(3) Through indirect tensile fatigue test, analysis and comparison of different length anddifferent dosage of basalt fiber reinforced asphalt concrete fatigue life, at the same timeaccording to the level of stress and fatigue life of the function relation between the fitting outof a two material fatigue parameters, based on the inherent fiber concrete fatiguecharacteristic parameter of quantitative evaluation, to analysis of basalt fiber on asphaltconcrete fatigue substantial cause for the performance improvement of.(4)The indirect tensile test to be of different lengths, different content of basalt fiberreinforced asphalt concrete load and horizontal displacement curve, introducing toughnessevaluation index, the basalt fiber asphalt concrete crack front split the overall behavioranalysis, quantitative evaluation of basalt fiber on asphalt concrete anti-crackingperformance improvement.(5) On different length, different content of basalt fiber reinforced asphalt concrete forthe viscoelastic properties were analyzed, using modified Burgers model, through the DanZhoujing load compression creep test result of time and displacement curve, fitting acharacterization of viscoelastic material property parameters, and then calculate the materialto the two internal time parameters, explore the basalt the addition of fiber on asphaltconcrete of high and low temperature performance improvement in essence.(6) Through microscopic analysis method, compared with the ordinary asphalt concreteand basalt fiber reinforced asphalt concrete internal microstructure fiber added, verify whether in asphalt concrete is formed inside the effective spatial network structure, whetherto exist inside the micro cracks and holes in the role of crack resistance and the restraintfunction, so that the asphalt concrete internal effective bearing area increased. Simultaneousobservation of different fiber content of each phase geometry characteristics, combined withcomposite view of the basalt fiber asphalt concrete performance evaluation.The results show that:(1) The basalt fiber improving the asphalt concrete water damage resistance and hightemperature deformation resistance; improve asphalt concrete in low temperature damagestrength and failure strain, reduces the failure stiffness, in which the failure strain increasemaximum reach43.72%, failure stiffness maximum reduce the value of25.86%, the asphaltconcrete at low temperature cracking resistance improved significantly.(2) The basalt fiber enhanced asphalt concrete fatigue life and fatigue properties of Kvalue and n value, and9mm long basalt fiber on asphalt concrete fatigue parameter n valueincreased significantly; basalt fiber enhanced asphalt concrete toughness index, reinforcedasphalt concrete cracking capacity, slow crack propagation speed, where9mm longcorresponding volume was0.05%,0.07%and6mm long corresponding dosage is0.15%ofthe basalt fiber on asphalt concrete toughness index improved most significantly, comparedto asphalt concrete crack after the use of quality improvement the best.(3)6mm and9mm long basalt fiber are improving the asphalt concrete the viscoelasticproperties of asphalt concrete, reduces the viscoelastic properties and internal timeparameters on the temperature variation in the degree of sensitivity, so that the asphaltconcrete in the external load down to recover less viscoelastic deformation cumulativevolume reduction, improvement of asphalt concrete under low temperature the stressrelaxation ability.(4) The basalt fiber and asphalt adhesion between fiber are good, because of the forcebeing broken, damaged surface of particles connected to strengthen, asphalt concrete existinside the micro cracks and holes in the role of crack resistance and the restraint function,thereby increasing the effective bearing area of asphalt concrete.(5) After a comprehensive analysis,9mm long, volume is0.07%of the basalt fiber on the water stability of asphalt concrete, fatigue resistance, toughness, viscoelastic propertiesimprovement of best, long6mm, volume is0.15%times of the basalt fiber; basalt fiber in theasphalt concrete, the uniformity of the distribution of basalt fiber and asphalt adhesion,basalt fibers, basalt fibers effective length direction are the main factors influencing thestrength of asphalt concrete.