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Shi X.,Changan University | Wang C.-H.,Changan University | Li Y.-W.,Transportation Bureau of Shijiazhuang | Zhao J.-J.,Changan University | Wang X.-C.,Changan University
Jiaotong Yunshu Gongcheng Xuebao/Journal of Traffic and Transportation Engineering

Two kinds of tourmaline powders and four kinds of tourmaline anion powders were selected to modify asphalt, and the tourmaline modified asphalt was prepared by using a melting-blending method. The penetration, softening point and ductility were tested, and the effect laws of tourmaline types and mixing amount on asphalt temperature sensitivity, high-temperature and low-temperature properties, adhesion property were studied. The effect of tourmaline on asphalt low-temperature property was studied by using improved bending beam rheometer(BBR) test, and the adhesion property between tourmaline modified asphalt and aggregate was evaluated by using water-boiling method. The improved mechanism of tourmaline on asphalt pavement performance was analyzed by using scanning electron microscope(SEM) test, differential scanning calorimetry(DSC) test, piezoelectric test and thermoelectric test. Analysis result shows that the temperature sensitivity of tourmaline powder modified asphalt improves firstly and then reduces with the increase of mixing amount, and that of tourmaline anion powder modified asphalt shows an opposite law. The high-temperature performances of all tourmaline modified asphalts improve with the increase of mixing amount. The pavement performance of tourmaline powder modified asphalt improves significantly with the increase of tourmaline powder mesh, that of tourmaline anion powder modified asphalt reduces unceasingly with the increase of anion release amount. In the same mesh, the effect of tourmaline anion powder on asphalt pavement performance is better than that of tourmaline powder. Tourmaline can well improve the low-temperature property of tourmaline modified asphalt. Tourmaline can disperse in asphalt uniformly and stably, and can form a stable whole. The electric property of tourmaline can be played fully when tourmaline is added into asphalt.So tourmaline can improve the road performance of asphalt significantly. Source

Wang C.-H.,Changan University | Chen S.,Changan University | Li Y.-W.,Changan University | Li Y.-W.,Tongji University | And 2 more authors.
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport

To solve the technical problems of power pavement based on piezoelectric transducers, piezoelectric elements that were applicable to generate electricity in the pavement were selected and several structural changes were implemented. Four kinds of protection measures were designed, and comprehensive performance evaluation indexes were put forward to determine optimal protection measure. Electrical output effect of small specimens with different combinations of typical layer structures was tested and evaluated, and energy harvesting circuit was developed and produced and its actual application effect was investigated. The results show that round piezoelectric ceramic element with diameter of 35 mm and thickness of 0.4 mm can meet the technical requirements of power pavement; structure improvement measures help to prolong service life of piezoelectric element obviously. Protection measure for structure combining D-type rigid copper with elastic rubber is the optimal measure. Electrical output effect of power pavement consisting of thin overlay composite AC-13 grading is optimal, which can continuously export 14 V peak voltage and 0.44 mW real output power for alternating current signal steadily. Improved circuit by energy harvesting standard can complete conversion and acquisition of piezoelectric micro energy of the road efficiently. © 2016, Editorial Department of China Journal of Highway and Transport. All right reserved. Source

Li R.,Changan University | Li Y.,Changan University | Shi X.,Transportation Bureau of Shijiazhuang | Liu Z.,Hubei Changjiang Road and Bridge Co. | And 2 more authors.
Journal Wuhan University of Technology, Materials Science Edition

Small stone asphalt mixture (SSAM) was designed by Bailey method and coarse aggregate voids-filling method. The optimum asphalt content was determined by Marshal test. Surface texture depth for SSAM with different voidage, and the BPN of SSAM and SMA before after wet track abrasion were measured. The experimental results indicate that the surface texture depth increases with the decreasing of asphalt aggregate ratio. The SSAM with the optimal asphalt content has a good skid resistance. BPN of asphalt mixture decreases with the increasing of wearing time, but the extent of reduction is different. The reduction rate of BPN for SSAM is smaller than that of SMA, indicating that SSAM has a good skid resistance attenuation capacity. Finally, the other properties of SSAM are also evaluated, showing that the splitting strength and modulus and SSAM are higher than those of SMA, and the other properties of SSAM, such as high-temperature performance and water stability can also satisfy the technical requirements. © 2012 Wuhan University of Technology and Springer-Verlag Berlin Heidelberg. Source

Li R.,Changan University | Pei J.,Changan University | Li Y.,Transportation Bureau of Shijiazhuang | Shi X.,Transportation Bureau of Shijiazhuang | Du Q.,Highway Administration Bureau of Hebei Province
Advanced Materials Research

A novel all-polymeric material with high dielectric constant (k) has been developed by blending poly (vinylidene fluoride) (PVDF) with polyamide-6 (PA6). The dependence of the dielectric properties on frequency and polymer volume fraction was investigated. When the volume fraction of PA6 is 20%, the dielectric property is better than others. The SEM investigations suggest that the enhanced dielectric behavior originates from significant interfacial interactions of polymer-polymer. The XRD demonstrate that the PA6 and PVDF affect the crystalline behavior of each component. Furthermore, the stable dielectric constants of the blends could be tuned by adjusting the content of the polymers. The created high-k all-polymeric blends represent a novel type of material that are simple technology and easy to process, and is of relatively high dielectric constant, applications as flexible electronics. © (2012) Trans Tech Publications, Switzerland. Source

Wang C.-H.,Changan University | Li Y.-W.,Transportation Bureau of Shijiazhuang | Ge J.,Tianjin Municipal Engineering Design and Research Institute | Wang P.,Changan University | Shi X.,Transportation Bureau of Shijiazhuang
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport

In order to solve the problem of serious pollution caused by preparation of asphalt mixture, tourmaline modified asphalt (TMA) was prepared. The waste gas and asphalt smoke were collected by self-assembled instrument and the most reasonable test method was determined by studying the effects of asphalt type, heating time, asphalt content and stirring rate. On that basis, the influence laws of the types and the mixing amount of tourmaline on asphalt smoke emission were systematically studied, and the emission reduction mechanism and road performance of tourmaline modified asphalt were also studied. The contrast test on emission of TMA mixture and commonly modified asphalt mixture was conducted with mix plant and test pavement emission detection. The results indicate that tourmaline can reduce the emission of asphalt smoke significantly. The tourmaline modified asphalt has excellent pyroelectricity, and it can release charges which can absorb smoke and dust under condition of being forced and heated, leading to an effect of emission reduction. The road performance of asphalt mixture can be improved significantly with the addition of tourmaline. It is verified that the emission reduction of tourmaline modified asphalt is quite obvious. ©, 2014, Xi'an Highway University. All right reserved. Source

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