Thermal oxidative and aging as an inevitable process in the practical application of road asphalt has great effect on the properties of asphalt. In this paper,the influences of short-term thermal oxidative ageing and ...Thermal oxidative and aging as an inevitable process in the practical application of road asphalt has great effect on the properties of asphalt. In this paper,the influences of short-term thermal oxidative ageing and ultraviolet radiation(UV) aging on the dynamic viscosity,penetration,softening point and rheological properties of two kinds of layered inorganic nano-powder including organo-modified montmorillonite (OMMT) and nanometer brucite (Mg(OH)2) modified asphalts were studied respectively. The rheological properties of these binders have been determined using a dynamic shear rheometer (DSR) through temperatures sweep tests.The rheological and physical analysis showed the two major influences of ageing on the properties for two kinds of layered inorganic nano-powder modified bitumens. On one hand,ageing decreased the viscous behaviors of modified binders,on the other hand,ageing improved the elastic behaviors of modified binders. The performances of binders after aging depended on the combined effect between the modifier and the bitumen. Both the two modifiers resisted the aging of bitumens and the effect of OMMT was better.展开更多
The objective of this paper is to propose a new quality evaluation method for asphalt concrete mixture using X-ray CT scanner.To achieve this aim,asphalt mixtures should be subjected to the X-ray CT scanning and its c...The objective of this paper is to propose a new quality evaluation method for asphalt concrete mixture using X-ray CT scanner.To achieve this aim,asphalt mixtures should be subjected to the X-ray CT scanning and its characteristics should be clarified.The approach employed in this study was as follows:1)Coarse aggregate,fine aggregate,filler and bitumen were prepared;2)dense-graded,coarse-graded and porous asphalt mixtures were made;3)materials and mixtures were subjected to the X-ray CT scanning;4)frequency of CT-value,threshold value,average slice CT-value,average segment CT-value were computed.In the material examination,CT-value of aggregate becomes smaller in the order of coarse aggregate,fine aggregate and filler and CT image of bitumen was nearly homogeneous.In the mixture examination,histograms of CT-value and four segmentation images made from CT images expressed the material and mixture characterization such as particle size and the difference in bitumen content and mixture type visibly and the bitumen content varies with the threshold values.In addition,the average segment CT-value without threshold value by dividing the fine aggregate from the coarse aggregate and average CT-value of the coarse aggregate,especially is highly correlated with average CT-value of the bitumen.展开更多
基金supported by the 2010 WHUT Ph.D.Candidate Intermational Academic Communication Preresearch Project(Pact No.2010-JL-02)
文摘Thermal oxidative and aging as an inevitable process in the practical application of road asphalt has great effect on the properties of asphalt. In this paper,the influences of short-term thermal oxidative ageing and ultraviolet radiation(UV) aging on the dynamic viscosity,penetration,softening point and rheological properties of two kinds of layered inorganic nano-powder including organo-modified montmorillonite (OMMT) and nanometer brucite (Mg(OH)2) modified asphalts were studied respectively. The rheological properties of these binders have been determined using a dynamic shear rheometer (DSR) through temperatures sweep tests.The rheological and physical analysis showed the two major influences of ageing on the properties for two kinds of layered inorganic nano-powder modified bitumens. On one hand,ageing decreased the viscous behaviors of modified binders,on the other hand,ageing improved the elastic behaviors of modified binders. The performances of binders after aging depended on the combined effect between the modifier and the bitumen. Both the two modifiers resisted the aging of bitumens and the effect of OMMT was better.
文摘The objective of this paper is to propose a new quality evaluation method for asphalt concrete mixture using X-ray CT scanner.To achieve this aim,asphalt mixtures should be subjected to the X-ray CT scanning and its characteristics should be clarified.The approach employed in this study was as follows:1)Coarse aggregate,fine aggregate,filler and bitumen were prepared;2)dense-graded,coarse-graded and porous asphalt mixtures were made;3)materials and mixtures were subjected to the X-ray CT scanning;4)frequency of CT-value,threshold value,average slice CT-value,average segment CT-value were computed.In the material examination,CT-value of aggregate becomes smaller in the order of coarse aggregate,fine aggregate and filler and CT image of bitumen was nearly homogeneous.In the mixture examination,histograms of CT-value and four segmentation images made from CT images expressed the material and mixture characterization such as particle size and the difference in bitumen content and mixture type visibly and the bitumen content varies with the threshold values.In addition,the average segment CT-value without threshold value by dividing the fine aggregate from the coarse aggregate and average CT-value of the coarse aggregate,especially is highly correlated with average CT-value of the bitumen.
