The fatigue property of asphalt mixtures under complicated environment （low-temperature bending performance, chloride penetration, freezing-thawing cycle and their coupling effect） and the improvement effect for rel...The fatigue property of asphalt mixtures under complicated environment （low-temperature bending performance, chloride penetration, freezing-thawing cycle and their coupling effect） and the improvement effect for relevant property of basalt fiber-reinforcing asphalt mixture under complicated environment are studied. Two grading types of asphalt mixtures, AC-16I and AC-13I, are chosen, whose optimum asphalt-aggregate ratio and optimum dosage of basalt fiber are determined by the Marshall test. The standard specimens are made firstly, and then the low temperature bending tests of asphalt mixture and basalt fiber-reinforced asphalt mixture under the coupling effect of the chloride erosion and freezing-thawing cycle have been carried out. Finally, the fatigue property tests of asphalt mixture and basalt fiber-reinforced asphalt mixture under complex environment are performed on MTS material testing system. The results indicate that the tensile strength, the maximum curving tensile stress, the curving stiffness modulus, and fatigue properties of asphalt mixture are influenced by the coupling effect of the chloride erosion and freezing-thawing cycle. The low-temperature bending performance and fatigue property of asphalt mixtures under complicated environment can be greatly improved by adding moderate basalt fiber. The dense gradation asphalt mixture possesses stronger ability to resist adverse environmental effects under the same condition.展开更多
The microstructure, electrical properties and density of ZnO-based varistor ceramics with different Er2O3 content prepared by high-energy ball milling （HEBM） and sintered at 800℃ were investigated. With increasing ...The microstructure, electrical properties and density of ZnO-based varistor ceramics with different Er2O3 content prepared by high-energy ball milling （HEBM） and sintered at 800℃ were investigated. With increasing Er2O3 content, the ZnO grain size decreases due to the Er-rich phases inhibiting grain growth ; and nonlinear coefficient （ α ） decreases because of the decrease of barrier height （φB） The breakdown voltage （Eb） and density increase, whereas leakage current （IL） decreases with increasing Er2O3 content. The barrier height （φB）, donor concentration （Nd）, density of interface states （Ns） decrease and barrier width （ω） increases with increasing Er2O3 content due to acceptor effect of Er2O3 in varistor ceramics.展开更多
基金Fund by Collaborative Innovation Center of Water Conservancy&Transportation Infrastructure Safety,Henan Province,China Postdoctoral Science Fund(No.20110491008)Science and Technology Planning Project of Department of Transportation of Henan Province(No.2013-2-12)The State Key Laboratory Open Fund of Harbor,Coastal and Offshore Engineering(No.LP1113)
文摘The fatigue property of asphalt mixtures under complicated environment （low-temperature bending performance, chloride penetration, freezing-thawing cycle and their coupling effect） and the improvement effect for relevant property of basalt fiber-reinforcing asphalt mixture under complicated environment are studied. Two grading types of asphalt mixtures, AC-16I and AC-13I, are chosen, whose optimum asphalt-aggregate ratio and optimum dosage of basalt fiber are determined by the Marshall test. The standard specimens are made firstly, and then the low temperature bending tests of asphalt mixture and basalt fiber-reinforced asphalt mixture under the coupling effect of the chloride erosion and freezing-thawing cycle have been carried out. Finally, the fatigue property tests of asphalt mixture and basalt fiber-reinforced asphalt mixture under complex environment are performed on MTS material testing system. The results indicate that the tensile strength, the maximum curving tensile stress, the curving stiffness modulus, and fatigue properties of asphalt mixture are influenced by the coupling effect of the chloride erosion and freezing-thawing cycle. The low-temperature bending performance and fatigue property of asphalt mixtures under complicated environment can be greatly improved by adding moderate basalt fiber. The dense gradation asphalt mixture possesses stronger ability to resist adverse environmental effects under the same condition.
基金Project supported by National Natural Science Foundation of China (50471045) Shanghai Nano-Technology PromotionCenter (0452nm026)
文摘The microstructure, electrical properties and density of ZnO-based varistor ceramics with different Er2O3 content prepared by high-energy ball milling （HEBM） and sintered at 800℃ were investigated. With increasing Er2O3 content, the ZnO grain size decreases due to the Er-rich phases inhibiting grain growth ; and nonlinear coefficient （ α ） decreases because of the decrease of barrier height （φB） The breakdown voltage （Eb） and density increase, whereas leakage current （IL） decreases with increasing Er2O3 content. The barrier height （φB）, donor concentration （Nd）, density of interface states （Ns） decrease and barrier width （ω） increases with increasing Er2O3 content due to acceptor effect of Er2O3 in varistor ceramics.
