Rheological characteristics of fiber-modified asphalt mixture were investigated.Cellulous fiber,polyester fiber and mineral fiber were used as additives for asphalt mixture,and the dosages were 0.3%,0.3%,0.4%,respecti...Rheological characteristics of fiber-modified asphalt mixture were investigated.Cellulous fiber,polyester fiber and mineral fiber were used as additives for asphalt mixture,and the dosages were 0.3%,0.3%,0.4%,respectively.Dynamic modulus test using superpave simple performance tester(SPT) was adopted to study the dynamic modulus and phase angle for the control mixture and fiber-modified ones at various temperatures and frequencies.Test results show that the rheological properties can be improved significantly by the addition of various fibers.The dynamic modulus increases with the increase of frequency,and the phase angle decreases with the increase of frequency.When various fibers are used,the dynamic modulus increases and phase angle decreases at each frequency.This indicates that the stiffness and the elastic portion of fiber-modified asphalt mixtures can be enhanced when various fibers are used,which results in the change of viscoelastic properties of mixtures.The creep test results show that the total strain and the permanent strain of asphalt mixtures during load-unload cycle can be significantly reduced,which results in the improvement of resistance to permanent deformation for asphalt mixtures containing various fiber additives.The Burgers model can be employed effectively to illustrate the rheological properties of fiber modified asphalt mixtures.展开更多
In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)o...In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)on as-phalt binders and investigate the effectiveness of DCLR in improving the performance of asphalt road.This paper prepared modifi ed petroleum as-phalt under diff erent process conditions and tested its penetration,softening point and ductility index.Based on the experimental data,according to gray correlation degree,the performance for the asphalt was compared.The performance for the modified asphalt is simulated and predicted using poly-nomial functions.The modifi ed asphalt was analyzed by FT-IR,TGA,SEM and HPLC.The results show that the optimal process conditions for DCLR modifi ed asphalt are shear mixing time of 45 min,shear mixing tempera-ture of 150℃ and shear mixing rate of 4000 r/min.The predicted fit with the experimental data of 0.993 further demonstrates the effectiveness of the method.The characterization results show no significant chemical change between the DCLR and the asphalt.DCLR can significantly improve the high temperature performance and water stability of the asphalt,but it has little impact on its low temperature performance.展开更多
基金Projects (NCET-05-0656) supported by Education Ministry for the New Century Excellent Talents,China
文摘Rheological characteristics of fiber-modified asphalt mixture were investigated.Cellulous fiber,polyester fiber and mineral fiber were used as additives for asphalt mixture,and the dosages were 0.3%,0.3%,0.4%,respectively.Dynamic modulus test using superpave simple performance tester(SPT) was adopted to study the dynamic modulus and phase angle for the control mixture and fiber-modified ones at various temperatures and frequencies.Test results show that the rheological properties can be improved significantly by the addition of various fibers.The dynamic modulus increases with the increase of frequency,and the phase angle decreases with the increase of frequency.When various fibers are used,the dynamic modulus increases and phase angle decreases at each frequency.This indicates that the stiffness and the elastic portion of fiber-modified asphalt mixtures can be enhanced when various fibers are used,which results in the change of viscoelastic properties of mixtures.The creep test results show that the total strain and the permanent strain of asphalt mixtures during load-unload cycle can be significantly reduced,which results in the improvement of resistance to permanent deformation for asphalt mixtures containing various fiber additives.The Burgers model can be employed effectively to illustrate the rheological properties of fiber modified asphalt mixtures.
文摘In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)on as-phalt binders and investigate the effectiveness of DCLR in improving the performance of asphalt road.This paper prepared modifi ed petroleum as-phalt under diff erent process conditions and tested its penetration,softening point and ductility index.Based on the experimental data,according to gray correlation degree,the performance for the asphalt was compared.The performance for the modified asphalt is simulated and predicted using poly-nomial functions.The modifi ed asphalt was analyzed by FT-IR,TGA,SEM and HPLC.The results show that the optimal process conditions for DCLR modifi ed asphalt are shear mixing time of 45 min,shear mixing tempera-ture of 150℃ and shear mixing rate of 4000 r/min.The predicted fit with the experimental data of 0.993 further demonstrates the effectiveness of the method.The characterization results show no significant chemical change between the DCLR and the asphalt.DCLR can significantly improve the high temperature performance and water stability of the asphalt,but it has little impact on its low temperature performance.
