Study On The Surface Modification Process Of Basalt Fiber And The Performance Of Modified Basalt Fiber Reinforced Asphalt Mucilage

At present,China's highway construction has entered a new period of upgrading renovation and maintenance.However,with the continuous optimization of mix proportion design of asphalt mixture,research and development of high performance road building materials and continuous improvement of construction technology,the early damage,ruts and cracks still occurred in some roads which can't satisfy people's daily travel requirements and greatly reduce the driving comfort.In order to solve these problems,the key is undoubtedly enhancing the interaction in different road building materials.This paper studied the surface modification process of basalt fiber by Silane coupling agent KH-550 and the performance of surface modified basalt fiber reinforced asphalt mucilage.Study used the Environmental Scanning Electron Microscope(ESEM),Fourier Transform Infrared Spectrometer(FTIR)and Energy Dispersve X-ray Spectrometer(EDX)to analize the surface modified basalt fiber.The reasonable concentration of KH-550 solution was 1.0% and the surface modification process should last 30 min.The pH,heat resistance,adhesion,absorbing ashphalt and segregability properties of surface modified basalt fiber were tested.The results showed that KH-550 did not affect the pH and heat resistance of modified fiber but modified fiber's abilities to adhere asphalt promoted by 1 level and to absorb asphalt increased by 65.5%.The dispersion of modified fiber in asphalt was effectively improved.Study used surface modified basalt fiber,Styrene-butadiene-styrene(SBS)modified asphalt and limestone powder to prepare the surface modified basalt fiber reinforced asphalt mucilage.The performance of low temperature,middle temperature and high temperature of these specimens were studied by 5? ductility test,25? elastic recovery test,40? cone penetration test and softening point test and then the enhancement mechanism of modified fiber reinforced asphalt mucilage was analyzed.The stiffness modulus,stiffness change rate,complex modulus,phase angle,rut factor and viscosity of these specimens were tested by bending beam rheometer tests(BBR),dynamic shear rheometer tests(DSR)and Brookfield rotation viscosity tests.The specimens of original basalt fiber reinforced asphalt mucilage were used to do parallel tests as comparisons.The results showed that the surface modified basalt fiber had good wettability with asphalt mucilage;the adhesion between modified fiber and asphalt mucilage was strong;modified fiber's surface film thickness of asphalt mucilage was large and the mechanical properties of it was significantly developed.When the powder asphalt ratio between 0.8 and 1.0 and the dosage of surface modified basalt fiber between 0.4% and 0.5%,the asphalt mucilage's abilities of anti high temperature shearing got significantly improved but the low temperature performance improvement was limited;the tensile strength,anti-shearing strength,elastic recovery ratio and softening point of asphalt mucilage were significantly enhanced which meant the abilities of low temperature anti-cracking,high temperature anti-shearing,fatigue performance and self-healing were improved.The modified fiber reinforced SBS asphalt mucilage's construction temperature should not less than 170?.The results provide the basis for the pretreatment of basalt fiber's surface and popularization and application of modified mineral fiber composites in road engineering.