The modification of asphalt binder with natural rubber latex(NR)significantly improves the rutting and fatigue resistance of asphalt mixtures.However,NR-modified binder is prone to low workability and wettability due ...The modification of asphalt binder with natural rubber latex(NR)significantly improves the rutting and fatigue resistance of asphalt mixtures.However,NR-modified binder is prone to low workability and wettability due to its high viscosity.Therefore,this research focuses on examining the influences of silane and wax-based additives on the wettability of natural rubber-modified binders and the binder-aggregates adhesion performances.In this study,experimental and analytical approaches were used.The contact angles of asphalt binder were measured using a goniometer through the sessile drop method with three solvents:deionised water,formamide,and glycerol.The Cþþalgorithm was adopted to compute the surface free energy(SFE)elements of the asphalt binder.Analytical methods were employed to analyse the results based on the Young-Dupre equation,followed by linear regression to establish a correlation between the compatibility ratio(CR)and the SFE components.The results inferred that modified asphalt binders with additives possessed improved moisture resistance,wherein dry work adhesion values were less than 210 mJ/m^(2)under granite interfaces,whereas the limestone interface exhibited higher dry adhesion values of 340 mJ/m^(2)and below.Similar performance results were observed under wet adhesion conditions;with granite wet adhesive values observed below 120 mJ/m^(2),while limestone wet adhesion values were ascertained below 180 mJ/m^(2)for all tested samples and conditions.According to the spread–ability coefficient results,the limestone interface has greater spread-ability than granite interfaces.Meanwhile,compatibility ratio values indicated better compatibility of 1.9 or higher for tested samples under granite interfaces,whereas compatibility values of 1.7 and below were observed under limestone interfaces.展开更多
EPDM price dropped withfluctuation in H1 2009Due to the global financial crisis, the demandfor EPDM (ethylene-propylene non-conjugateddiene rubber) was slack and its pricealso fell rapidly in the second half of 2008.C...EPDM price dropped withfluctuation in H1 2009Due to the global financial crisis, the demandfor EPDM (ethylene-propylene non-conjugateddiene rubber) was slack and its pricealso fell rapidly in the second half of 2008.China issued quite a few macro policies topromote the domestic demand in 2009 andinitial results were produced. Due to abundantresources and slack demand, however,the price of EPDM still dropped in H1 (thefirst half of) 2009.展开更多
基金The authors sincerely acknowledge the Ministry of Higher Education,Malaysia for the Fundamental Research Grant Scheme with Project Code:FRGS/1/2021/TK01/USM/02/1 that enabled them to conduct this research work.Special thanks to material suppliers for extending their support.The authors also express their appreciation to the technicians of the Highway Engineering Laboratory and Materials Engineering Laboratory at Universiti Sains Malaysia for their help.
文摘The modification of asphalt binder with natural rubber latex(NR)significantly improves the rutting and fatigue resistance of asphalt mixtures.However,NR-modified binder is prone to low workability and wettability due to its high viscosity.Therefore,this research focuses on examining the influences of silane and wax-based additives on the wettability of natural rubber-modified binders and the binder-aggregates adhesion performances.In this study,experimental and analytical approaches were used.The contact angles of asphalt binder were measured using a goniometer through the sessile drop method with three solvents:deionised water,formamide,and glycerol.The Cþþalgorithm was adopted to compute the surface free energy(SFE)elements of the asphalt binder.Analytical methods were employed to analyse the results based on the Young-Dupre equation,followed by linear regression to establish a correlation between the compatibility ratio(CR)and the SFE components.The results inferred that modified asphalt binders with additives possessed improved moisture resistance,wherein dry work adhesion values were less than 210 mJ/m^(2)under granite interfaces,whereas the limestone interface exhibited higher dry adhesion values of 340 mJ/m^(2)and below.Similar performance results were observed under wet adhesion conditions;with granite wet adhesive values observed below 120 mJ/m^(2),while limestone wet adhesion values were ascertained below 180 mJ/m^(2)for all tested samples and conditions.According to the spread–ability coefficient results,the limestone interface has greater spread-ability than granite interfaces.Meanwhile,compatibility ratio values indicated better compatibility of 1.9 or higher for tested samples under granite interfaces,whereas compatibility values of 1.7 and below were observed under limestone interfaces.
文摘EPDM price dropped withfluctuation in H1 2009Due to the global financial crisis, the demandfor EPDM (ethylene-propylene non-conjugateddiene rubber) was slack and its pricealso fell rapidly in the second half of 2008.China issued quite a few macro policies topromote the domestic demand in 2009 andinitial results were produced. Due to abundantresources and slack demand, however,the price of EPDM still dropped in H1 (thefirst half of) 2009.
